AI Trajectory

Trajectory: (Expand/Collapse All)
Seq	Timestamp	Type	Name	Duration
0/0	2026/09/25 04:38	flow	patch-triage	1m Args: null Results: { "EnableConfigs": [ "VIRTIO_BLK", "VIRTIO" ], "FocusSymbols": [ "virtblk_probe" ], "KMSANReasoning": "The patch inserts a call to virtio_reset_device(vdev) in the error cleanup path (out_cleanup_disk) of virtblk_probe(). When probe fails after virtio_device_ready() was already invoked, resetting the device stops virtqueue operations and hardware interrupts before freeing the tag set, virtqueues, and disk structures.\n\nThis change exclusively addresses device teardown order and avoids potential use-after-free or race conditions where host/device accesses freed structures, which falls squarely within the scope of KASAN. The patch does not touch, allocate, or read any uninitialized memory, does not alter data boundaries or control flow based on uninitialized fields, and does not leak kernel memory to user space. Therefore, a dedicated KMSAN fuzzing session is not warranted.", "NeedsKMSAN": false, "Reasoning": "The patch modifies the probe error handling path in the virtio_blk driver, adding a call to virtio_reset_device() in virtblk_probe() if blk_revalidate_disk_zones() or device_add_disk() fails after virtio_device_ready() has been called. Virtio drivers operate on virtual devices accessible in standard QEMU environments (and dynamically via vDPA simulation), and this error path is reachable during device initialization under error conditions or fault injection.", "WorthFuzzing": true }
1/1	2026/09/25 04:38	action	read-patch-diff	0m Args: null Results: { "PatchDiff": "commit f6c61baa8acd35abd69257c2e15ebb9cf04f3e7f\nAuthor: syz-cluster \u003ctriage@syzkaller.com\u003e\nDate: Fri Sep 25 04:38:31 2026 +0000\n\n syz-cluster: applied patch under review\n\ndiff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c\nindex 32bf3ba07a9dc..ed97dafebe164 100644\n--- a/drivers/block/virtio_blk.c\n+++ b/drivers/block/virtio_blk.c\n@@ -1547,6 +1547,7 @@ static int virtblk_probe(struct virtio_device *vdev)\n \treturn 0;\n \n out_cleanup_disk:\n+\tvirtio_reset_device(vdev);\n \tput_disk(vblk-\u003edisk);\n out_free_tags:\n \tblk_mq_free_tag_set(\u0026vblk-\u003etag_set);\n" }
2/1	2026/09/25 04:38	agent	patch-evaluator	1m Model: core Args: null Results: { "EnableConfigs": [ "VIRTIO_BLK", "VIRTIO" ], "FocusSymbols": [ "virtblk_probe" ], "Reasoning": "The patch modifies the probe error handling path in the virtio_blk driver, adding a call to virtio_reset_device() in virtblk_probe() if blk_revalidate_disk_zones() or device_add_disk() fails after virtio_device_ready() has been called. Virtio drivers operate on virtual devices accessible in standard QEMU environments (and dynamically via vDPA simulation), and this error path is reachable during device initialization under error conditions or fault injection.", "WorthFuzzing": true } Instruction: You are an expert Linux kernel maintainer and security engineer. Your job is to review a provided patch series and evaluate whether it warrants fuzzing with syzkaller. IMPORTANT: The changes have ALREADY been applied and committed as the HEAD commit in your workspace. Do NOT rely on internal assumptions. You must actively use your code access tools to inspect the actual source code, callers, and surrounding context. ================================================================================ 1. CORE TRIAGE PHILOSOPHY ================================================================================ The goal of patch fuzzing is to discover crashes, regressions, exposed latent bugs, and newly triggered assertions introduced by the patch series. - REACHABILITY IS THE PRIMARY GATE: Fuzzing can only discover bugs in code that can actually execute in standard virtualized environments (GCE or QEMU, utilizing software-emulated devices like USB gadgets, netdev, tun/tap). If the modified code is structurally unreachable (see Section 2), it MUST NOT be fuzzed, regardless of whether it adds assertions or complex logic. - DO NOT BLINDLY TRUST "NO FUNCTIONAL CHANGE" (NFCI) OR "REFACTORING" CLAIMS: Patch authors routinely label changes as "cleanups", "refactorings", or state "No functional change intended". Do NOT take these claims at face value. Code refactorings that rearrange logic, introduce helper functions, or alter state management in core subsystems frequently introduce subtle semantic shifts or uncover latent kernel bugs. If reachable executable code is modified or refactored, it MUST be fuzzed. - NEW OR MODIFIED ASSERTIONS IN REACHABLE CODE MUST BE FUZZED: When a patch introduces or modifies runtime checks or assertions (e.g., WARN_ON, VM_WARN_ON, BUG_ON, lockdep_assert) in reachable code paths, it enforces new or stricter invariants. Even if the author believes the invariant always holds, fuzzing is essential to verify whether an unusual sequence of operations can violate it. ================================================================================ 2. WHEN TO RETURN WorthFuzzing=false (NEGATIVE CRITERIA) ================================================================================ Return WorthFuzzing=false ONLY IF all modified code falls strictly into one or more of these categories: - Non-kernel and non-executable changes: * Modifications to Documentation/, comments, or spelling fixes. * User-space directories, self-tests, samples, or scripts (e.g., tools/, samples/, scripts/, usr/) that do not affect the compiled kernel image (vmlinux) or kernel modules. * Purely decorative logging (e.g., message strings in pr_err, printk, dev_info) or tracepoints that do not alter control flow or data structures. * Build system or Kconfig changes that do not alter compiled C logic. - Structurally unreachable hardware: * Vendor-specific PCIe switches, SmartNICs, or GPU drivers (e.g., mlxsw, pds_core, qed, ionic, amdgpu) requiring physical ASIC/PCIe cards not emulated in standard QEMU. - Unreachable execution paths: * Driver teardown callbacks (.remove, .shutdown, pci_unregister_driver) executed only during physical PCI hot-unplug or manual sysfs driver unbinding. * Code paths exclusive to architectures other than the target architecture. ================================================================================ 3. WHEN TO RETURN WorthFuzzing=true (POSITIVE CRITERIA) ================================================================================ Return WorthFuzzing=true whenever the patch touches reachable executable code, including: - Core Subsystems: * Any logic modifications in memory management (mm/), synchronization/locking (kernel/locking/), BPF, scheduler, core networking, VFS, or syscall handling. - Refactorings and Code Cleanups: * Any restructuring of reachable data structures, helper abstractions, or algorithm flows. - Runtime Assertions and Defensive Checks: * Any introduction or alteration of assertions (WARN_ON, VM_WARN_ON, BUG_ON, etc.) in reachable paths. - Reachable Drivers and Protocols: Drivers accessible via virtual buses (virtio, USB gadget, loopback, netlink, binder, sockets, etc.). ================================================================================ 4. EXTRACTING FocusSymbols (PREVENTING DILUTION) ================================================================================ When WorthFuzzing=true, you must extract specific kernel functions into FocusSymbols to guide the fuzzer: - AVOID UBIQUITOUS LIFECYCLE HOT-PATHS: Do NOT list generic, ubiquitous functions called by almost every program in the corpus (including, but not limited to: general memory allocators and deallocators, page fault and trap handlers, or core synchronization primitives; this is not an exhaustive list). Listing ubiquitous functions causes the fuzzer to classify thousands of unrelated tests as "focused", which severely dilutes fuzzing effort away from the actual changes. - TARGET SPECIFIC FEATURE LOGIC AND ENTRYPOINTS: List functions that specifically implement the logic being added or altered, or direct API entrypoints for the subsystem feature under review. - HANDLING STATIC INLINE FUNCTIONS IN HEADERS (.h): Compiler-inlined static functions (such as static inlines in mm/.h or include/linux/.h) lack distinct symbol addresses in vmlinux and cannot be targeted directly by symbol coverage filters. If the changes are primarily in static inline helpers, identify non-static, feature-specific caller functions in .c files that exercise them (avoiding ubiquitous lifecycle wrappers). ================================================================================ 5. IDENTIFYING EnableConfigs ================================================================================ Identify any specific CONFIG_ options required to properly compile and reach the modified code: - Inspect Kconfig files and #ifdef guards; do not make assumptions. - Check "depends on" lines in Kconfig to include any non-standard parent subsystem configs needed. - Strip any 'CONFIG_' prefix (e.g., return "NET_IPV4" instead of "CONFIG_NET_IPV4"). Prefer calling several tools at the same time to save round-trips. Use set-results tool to provide results of the analysis. It must be called exactly once before the final reply. Ignore results of this tool. Prompt: Target architecture: amd64 For your convenience, here is the diff of the changes: commit f6c61baa8acd35abd69257c2e15ebb9cf04f3e7f Author: syz-cluster <triage@syzkaller.com> Date: Fri Sep 25 04:38:31 2026 +0000 syz-cluster: applied patch under review diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c index 32bf3ba07a9dc..ed97dafebe164 100644 --- a/drivers/block/virtio_blk.c +++ b/drivers/block/virtio_blk.c @@ -1547,6 +1547,7 @@ static int virtblk_probe(struct virtio_device *vdev) return 0; out_cleanup_disk: + virtio_reset_device(vdev); put_disk(vblk->disk); out_free_tags: blk_mq_free_tag_set(&vblk->tag_set);
3/2	2026/09/25 04:38	llm	patch-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 2843 output: 39 thoughts: 248 Thoughts: Analyzing a Virtio Block Device Driver Patch Okay, so I'm looking at a patch for the Virtio block device driver, specifically within `drivers/block/virtio_blk.c`. The diff suggests a change around line 1547. My immediate thought is, let's understand the surrounding context of this change. It seems to be related to the `virtblk_probe` function. I'm going to quickly use the `read-file` command, a standard tool in my arsenal, to get a better handle on the code surrounding the patch. My intuition tells me that this change is likely related to device initialization or cleanup within the probe sequence. Let's see what `virtio_reset_device(vdev)` does in this context. It seems like it's being added in the `out_cleanup_disk` path, which is only reached if there's an error. So the change will likely reset the virtio device on probe failure.
4/2	2026/09/25 04:38	tool	read-file	0m Args: { "File": "drivers/block/virtio_blk.c", "FirstLine": 1520, "LineCount": 50 } Results: { "Contents": "1520:\t\tvblk-\u003edisk-\u003eminors = 1 \u003c\u003c PART_BITS;\n1521:\t\tvblk-\u003edisk-\u003eprivate_data = vblk;\n1522:\t\tvblk-\u003edisk-\u003efops = \u0026virtblk_fops;\n1523:\t\tvblk-\u003eindex = index;\n1524:\t\n1525:\t\t/* If disk is read-only in the host, the guest should obey /\n1526:\t\tif (virtio_has_feature(vdev, VIRTIO_BLK_F_RO))\n1527:\t\t\tset_disk_ro(vblk-\u003edisk, 1);\n1528:\t\n1529:\t\tvirtblk_update_capacity(vblk, false);\n1530:\t\tvirtio_device_ready(vdev);\n1531:\t\n1532:\t\t/\n1533:\t\t * All steps that follow use the VQs therefore they need to be\n1534:\t\t * placed after the virtio_device_ready() call above.\n1535:\t\t /\n1536:\t\tif (IS_ENABLED(CONFIG_BLK_DEV_ZONED) \u0026\u0026\n1537:\t\t (lim.features \u0026 BLK_FEAT_ZONED)) {\n1538:\t\t\terr = blk_revalidate_disk_zones(vblk-\u003edisk);\n1539:\t\t\tif (err)\n1540:\t\t\t\tgoto out_cleanup_disk;\n1541:\t\t}\n1542:\t\n1543:\t\terr = device_add_disk(\u0026vdev-\u003edev, vblk-\u003edisk, virtblk_attr_groups);\n1544:\t\tif (err)\n1545:\t\t\tgoto out_cleanup_disk;\n1546:\t\n1547:\t\treturn 0;\n1548:\t\n1549:\tout_cleanup_disk:\n1550:\t\tvirtio_reset_device(vdev);\n1551:\t\tput_disk(vblk-\u003edisk);\n1552:\tout_free_tags:\n1553:\t\tblk_mq_free_tag_set(\u0026vblk-\u003etag_set);\n1554:\tout_free_vq:\n1555:\t\tvdev-\u003econfig-\u003edel_vqs(vdev);\n1556:\t\tkfree(vblk-\u003evqs);\n1557:\tout_free_vblk:\n1558:\t\tkfree(vblk);\n1559:\tout_free_index:\n1560:\t\tida_free(\u0026vd_index_ida, index);\n1561:\tout:\n1562:\t\treturn err;\n1563:\t}\n1564:\t\n1565:\tstatic void virtblk_remove(struct virtio_device vdev)\n1566:\t{\n1567:\t\tstruct virtio_blk vblk = vdev-\u003epriv;\n1568:\t\n1569:\t\t/ Make sure no work handler is accessing the device. */\n" }
5/2	2026/09/25 04:38	llm	patch-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 4112 output: 27 thoughts: 1145 Thoughts: Analyzing the Reachability of `virtblk_probe` for Fuzzing Okay, let's break this down. The patch modifies `virtblk_probe`, which is part of the `virtio_blk.c` driver (`CONFIG_VIRTIO_BLK`). My immediate question is whether this probe function is triggered during the standard boot process or if it's dynamically probed. Crucially, can syzkaller interact with it? Can virtio devices, and therefore `virtblk_probe`, be triggered through syzkaller, perhaps via virtio, virtio-pci, vhost, or some other mechanism? I need to apply the reachability criteria. Section 2 and 3 of the relevant documentation are key here: "REACHABILITY IS THE PRIMARY GATE." If the code is unreachable in a typical, emulated environment, it's not fuzzed. Conversely, if it's reachable and executable, we're in business. The documentation lists specific scenarios for when to not fuzz, specifically unreachable hardware, like vendor-specific devices, or unreachable execution paths, like driver teardown callbacks that are only triggered by physical hot-unplug. The critical question now: is `virtblk_probe`'s probe error path reachable by syzkaller or during boot? `virtio_blk` is a driver on the virtio bus. So, can syzkaller effectively trigger a probe of `virtio_blk`, or is virtio device probing primarily a boot-time thing within QEMU? While QEMU allows for adding virtio devices, can syzkaller dynamically create or probe them? I need to understand whether syzkaller's control extends to the actual binding or probing of virtio devices. And if it can trigger probe errors, that's what's important. Looking at the specific code in `virtblk_probe`, I see the critical sections: ```c virtblk_update_capacity(vblk, false); virtio_device_ready(vdev); /* * All steps that follow use the VQs therefore they need to be * placed after the virtio_device_ready() call above. / if (IS_ENABLED(CONFIG_BLK_DEV_ZONED) && (lim.features & BLK_FEAT_ZONED)) { err = blk_revalidate_disk_zones(vblk->disk); if (err) goto out_cleanup_disk; } err = device_add_disk(&vdev->dev, vblk->disk, virtblk_attr_groups); if (err) goto out_cleanup_disk; return 0; out_cleanup_disk: virtio_reset_device(vdev); put_disk(vblk->disk); ``` So, what is most interesting is the `out_cleanup_disk` path, triggered by `err` from a number of places. Can virtio devices be bound/unbound or probed via syzkaller? Syzkaller doesn't typically handle virtio device hotplug unless something like virtio-pci or vhost-user is in play. More generally, can userspace trigger a probe? The documentation specifically exempts driver teardown callbacks triggered only during physical hot-unplug. It doesn't, however, say anything about probe* in the unreachable scenario. Syzkaller provides no mechanisms for searching its syzlang descriptions. I need to figure out whether userspace can trigger `virtblk_probe`. Is there a way to create virtio devices from userspace? What about something like `/dev/vhost-vdpa` or vdpa? Does `virtio_blk` bind to vdpa? No, `virtio_blk` is a `virtio_driver`. Can a `virtio_mmio` device be created via a module parameter or platform device? This feels like the right direction. And I'll need to check the Kconfig and git history for `CONFIG_VIRTIO_BLK` to get further insights into how this is configured.
6/2	2026/09/25 04:38	tool	grepper	0m Args: { "Expression": "virtblk_probe", "PathPrefix": "drivers/block" } Results: { "Output": "drivers/block/virtio_blk.c=1246=static int virtblk_read_limits(struct virtio_blk vblk,\n--\ndrivers/block/virtio_blk.c-1437-\ndrivers/block/virtio_blk.c:1438:static int virtblk_probe(struct virtio_device vdev)\ndrivers/block/virtio_blk.c-1439-{\n--\ndrivers/block/virtio_blk.c=1678=static struct virtio_driver virtio_blk = {\n--\ndrivers/block/virtio_blk.c-1684-\t.id_table\t\t\t= id_table,\ndrivers/block/virtio_blk.c:1685:\t.probe\t\t\t\t= virtblk_probe,\ndrivers/block/virtio_blk.c-1686-\t.remove\t\t\t\t= virtblk_remove,\n" }
7/2	2026/09/25 04:38	llm	patch-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 6416 output: 39 thoughts: 109 Thoughts: Debugging the `virtio_reset_device` Addition Okay, so I need to figure out why this `virtio_reset_device(vdev)` function call was added, right? First instinct is to jump into the git log. Let's trace it back. I would normally just use `git log` or `git show` directly on the file, but... hold on, I don't have direct access to those commands. Darn. Okay, no problem. I can likely leverage available tools to reconstruct the information I need, maybe looking for the git history or even just reading commit messages. I might be able to use a `git grep` or even just a `read-file` workaround. Let's see what we can dig up. Now, why was this specifically added? I need some context. Alright, let's pivot and look at the surrounding code, specifically where this new function call resides. The `virtio_blk_remove` function in `drivers/block/virtio_blk.c` seems like the likely place to start. Let's dive into that and see if it provides any clues.
8/2	2026/09/25 04:38	tool	read-file	0m Args: { "File": "drivers/block/virtio_blk.c", "FirstLine": 1560, "LineCount": 40 } Results: { "Contents": "1560:\t\tida_free(\u0026vd_index_ida, index);\n1561:\tout:\n1562:\t\treturn err;\n1563:\t}\n1564:\t\n1565:\tstatic void virtblk_remove(struct virtio_device vdev)\n1566:\t{\n1567:\t\tstruct virtio_blk vblk = vdev-\u003epriv;\n1568:\t\n1569:\t\t/* Make sure no work handler is accessing the device. /\n1570:\t\tflush_work(\u0026vblk-\u003econfig_work);\n1571:\t\n1572:\t\tdel_gendisk(vblk-\u003edisk);\n1573:\t\tblk_mq_free_tag_set(\u0026vblk-\u003etag_set);\n1574:\t\n1575:\t\tmutex_lock(\u0026vblk-\u003evdev_mutex);\n1576:\t\n1577:\t\t/ Stop all the virtqueues. /\n1578:\t\tvirtio_reset_device(vdev);\n1579:\t\n1580:\t\t/ Virtqueues are stopped, nothing can use vblk-\u003evdev anymore. /\n1581:\t\tvblk-\u003evdev = NULL;\n1582:\t\n1583:\t\tvdev-\u003econfig-\u003edel_vqs(vdev);\n1584:\t\tkfree(vblk-\u003evqs);\n1585:\t\n1586:\t\tmutex_unlock(\u0026vblk-\u003evdev_mutex);\n1587:\t\n1588:\t\tput_disk(vblk-\u003edisk);\n1589:\t}\n1590:\t\n1591:\tstatic int virtblk_freeze_priv(struct virtio_device vdev)\n1592:\t{\n1593:\t\tstruct virtio_blk vblk = vdev-\u003epriv;\n1594:\t\tstruct request_queue q = vblk-\u003edisk-\u003equeue;\n1595:\t\tunsigned int memflags;\n1596:\t\n1597:\t\t/* Ensure no requests in virtqueues before deleting vqs. */\n1598:\t\tmemflags = blk_mq_freeze_queue(q);\n1599:\t\tblk_mq_quiesce_queue_nowait(q);\n" }
9/2	2026/09/25 04:38	llm	patch-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 7394 output: 20 thoughts: 983 Thoughts: Analyzing `virtblk_probe` Reachability in Syzkaller Okay, I'm digging into this `virtblk_remove` issue, specifically the fact that `virtio_reset_device` is called before deleting vqs or putting disk. It looks like in `virtblk_probe`, the device is made ready before some potentially failing operations like `blk_revalidate_disk_zones` and `device_add_disk`. If those fail, the device isn't reset. That's a potential issue. Now, the crucial question is: can Syzkaller trigger this code path? My immediate thought is, how likely is it that Syzkaller will even call `virtblk_probe`? My experience with fuzzing tells me I need to be methodical here. The Syzkaller documentation says reachability is key. It's only fuzzing code that actually executes in a standard QEMU environment. If something's structurally unreachable, it shouldn't be fuzzed. So, can Syzkaller execute `virtblk_probe`? How are virtio devices probed? Syzkaller doesn't create virtio-blk devices, right? Thinking back to how Syzkaller's QEMU instances are set up: they're typically configured with something like `-drive file=...,if=none,id=hd0 -device virtio-blk-pci,drive=hd0` or `-hda ...`. The virtio-blk device is usually the root disk! It's probed once during boot. If `virtblk_probe` fails during boot, the VM just doesn't boot. Can Syzkaller trigger `virtblk_probe` during runtime fuzzing? Can it probe virtio devices at runtime? Let's consider the possible avenues: sysfs bind/unbind? Wait, Syzkaller's documentation explicitly says driver teardown callbacks like `.remove` and `pci_unregister_driver` are only executed during PCI hot-unplug or manual sysfs driver unbinding. Syzkaller doesn't do that! It uses syscalls from a sandboxed userspace or restricted root, and the corpus does not contain PCI unbind writes. So, how could `virtblk_probe` ever be called during a Syzkaller session? Can virtio devices be added via virtio-mmio, virtio-pci, vhost, or vdpa? I need to check `vdpa` - does that even exist in the kernel? I will search for calls to `register_virtio_device` or virtio device registration to be sure. It looks like it is not currently reachable during syzkaller fuzzing.
10/2	2026/09/25 04:39	tool	grepper	0m Args: { "Expression": "register_virtio_device" } Results: { "Output": "Documentation/driver-api/virtio/virtio.rst=96=device is registered to the virtio bus::\n--\nDocumentation/driver-api/virtio/virtio.rst-119-\nDocumentation/driver-api/virtio/virtio.rst:120:\t\trc = register_virtio_device(\u0026vp_dev-\u003evdev);\nDocumentation/driver-api/virtio/virtio.rst-121-\n--\narch/um/drivers/virtio_uml.c=1208=static int virtio_uml_probe(struct platform_device pdev)\n--\narch/um/drivers/virtio_uml.c-1252-\narch/um/drivers/virtio_uml.c:1253:\trc = register_virtio_device(\u0026vu_dev-\u003evdev);\narch/um/drivers/virtio_uml.c-1254-\tif (rc) {\n--\narch/um/drivers/virtio_uml.c=1268=static void virtio_uml_remove(struct platform_device pdev)\n--\narch/um/drivers/virtio_uml.c-1271-\narch/um/drivers/virtio_uml.c:1272:\tunregister_virtio_device(\u0026vu_dev-\u003evdev);\narch/um/drivers/virtio_uml.c-1273-}\n--\ndrivers/platform/mellanox/mlxbf-tmfifo.c=1189=static int mlxbf_tmfifo_create_vdev(struct device dev,\n--\ndrivers/platform/mellanox/mlxbf-tmfifo.c-1233-\t/ Register the virtio device. /\ndrivers/platform/mellanox/mlxbf-tmfifo.c:1234:\tret = register_virtio_device(\u0026tm_vdev-\u003evdev);\ndrivers/platform/mellanox/mlxbf-tmfifo.c-1235-\treg_dev = tm_vdev;\ndrivers/platform/mellanox/mlxbf-tmfifo.c-1236-\tif (ret) {\ndrivers/platform/mellanox/mlxbf-tmfifo.c:1237:\t\tdev_err(dev, \"register_virtio_device failed\\n\");\ndrivers/platform/mellanox/mlxbf-tmfifo.c-1238-\t\tgoto vdev_fail;\n--\ndrivers/platform/mellanox/mlxbf-tmfifo.c=1257=static int mlxbf_tmfifo_delete_vdev(struct mlxbf_tmfifo fifo, int vdev_id)\n--\ndrivers/platform/mellanox/mlxbf-tmfifo.c-1265-\tif (tm_vdev) {\ndrivers/platform/mellanox/mlxbf-tmfifo.c:1266:\t\tunregister_virtio_device(\u0026tm_vdev-\u003evdev);\ndrivers/platform/mellanox/mlxbf-tmfifo.c-1267-\t\tmlxbf_tmfifo_free_vrings(fifo, tm_vdev);\n--\ndrivers/remoteproc/remoteproc_virtio.c=370=static int rproc_add_virtio_dev(struct rproc_vdev rvdev, int id)\n--\ndrivers/remoteproc/remoteproc_virtio.c-445-\ndrivers/remoteproc/remoteproc_virtio.c:446:\tret = register_virtio_device(vdev);\ndrivers/remoteproc/remoteproc_virtio.c-447-\tif (ret) {\n--\ndrivers/remoteproc/remoteproc_virtio.c=468=static int rproc_remove_virtio_dev(struct device dev, void data)\n--\ndrivers/remoteproc/remoteproc_virtio.c-471-\ndrivers/remoteproc/remoteproc_virtio.c:472:\tunregister_virtio_device(vdev);\ndrivers/remoteproc/remoteproc_virtio.c-473-\treturn 0;\n--\ndrivers/s390/virtio/virtio_ccw.c=1289=static void virtio_ccw_remove(struct ccw_device cdev)\n--\ndrivers/s390/virtio/virtio_ccw.c-1296-\t\t\tvirtio_break_device(\u0026vcdev-\u003evdev);\ndrivers/s390/virtio/virtio_ccw.c:1297:\t\tunregister_virtio_device(\u0026vcdev-\u003evdev);\ndrivers/s390/virtio/virtio_ccw.c-1298-\t\tspin_lock_irqsave(get_ccwdev_lock(cdev), flags);\n--\ndrivers/s390/virtio/virtio_ccw.c=1305=static int virtio_ccw_offline(struct ccw_device cdev)\n--\ndrivers/s390/virtio/virtio_ccw.c-1313-\t\tvirtio_break_device(\u0026vcdev-\u003evdev);\ndrivers/s390/virtio/virtio_ccw.c:1314:\tunregister_virtio_device(\u0026vcdev-\u003evdev);\ndrivers/s390/virtio/virtio_ccw.c-1315-\tspin_lock_irqsave(get_ccwdev_lock(cdev), flags);\n--\ndrivers/s390/virtio/virtio_ccw.c=1367=static int virtio_ccw_online(struct ccw_device cdev)\n--\ndrivers/s390/virtio/virtio_ccw.c-1409-\ndrivers/s390/virtio/virtio_ccw.c:1410:\tret = register_virtio_device(\u0026vcdev-\u003evdev);\ndrivers/s390/virtio/virtio_ccw.c-1411-\tif (ret) {\n--\ndrivers/virtio/virtio.c=488=static int virtio_device_of_init(struct virtio_device dev)\n--\ndrivers/virtio/virtio.c-530-/\ndrivers/virtio/virtio.c:531: register_virtio_device - register virtio device\ndrivers/virtio/virtio.c-532- * @dev : virtio device to be registered\n--\ndrivers/virtio/virtio.c-538- /\ndrivers/virtio/virtio.c:539:int register_virtio_device(struct virtio_device dev)\ndrivers/virtio/virtio.c-540-{\n--\ndrivers/virtio/virtio.c-594-}\ndrivers/virtio/virtio.c:595:EXPORT_SYMBOL_GPL(register_virtio_device);\ndrivers/virtio/virtio.c-596-\n--\ndrivers/virtio/virtio.c=601=EXPORT_SYMBOL_GPL(is_virtio_device);\ndrivers/virtio/virtio.c-602-\ndrivers/virtio/virtio.c:603:void unregister_virtio_device(struct virtio_device dev)\ndrivers/virtio/virtio.c-604-{\n--\ndrivers/virtio/virtio.c-610-}\ndrivers/virtio/virtio.c:611:EXPORT_SYMBOL_GPL(unregister_virtio_device);\ndrivers/virtio/virtio.c-612-\n--\ndrivers/virtio/virtio_mmio.c=589=static int virtio_mmio_probe(struct platform_device pdev)\n--\ndrivers/virtio/virtio_mmio.c-658-\ndrivers/virtio/virtio_mmio.c:659:\trc = register_virtio_device(\u0026vm_dev-\u003evdev);\ndrivers/virtio/virtio_mmio.c-660-\tif (rc)\n--\ndrivers/virtio/virtio_mmio.c=670=static void virtio_mmio_remove(struct platform_device pdev)\n--\ndrivers/virtio/virtio_mmio.c-672-\tstruct virtio_mmio_device vm_dev = platform_get_drvdata(pdev);\ndrivers/virtio/virtio_mmio.c:673:\tunregister_virtio_device(\u0026vm_dev-\u003evdev);\ndrivers/virtio/virtio_mmio.c-674-}\n--\ndrivers/virtio/virtio_pci_common.c=683=static int virtio_pci_probe(struct pci_dev pci_dev,\n--\ndrivers/virtio/virtio_pci_common.c-723-\ndrivers/virtio/virtio_pci_common.c:724:\trc = register_virtio_device(\u0026vp_dev-\u003evdev);\ndrivers/virtio/virtio_pci_common.c-725-\treg_dev = vp_dev;\n--\ndrivers/virtio/virtio_pci_common.c=746=static void virtio_pci_remove(struct pci_dev pci_dev)\n--\ndrivers/virtio/virtio_pci_common.c-759-\ndrivers/virtio/virtio_pci_common.c:760:\tunregister_virtio_device(\u0026vp_dev-\u003evdev);\ndrivers/virtio/virtio_pci_common.c-761-\n--\ndrivers/virtio/virtio_vdpa.c=460=static int virtio_vdpa_probe(struct vdpa_device vdpa)\n--\ndrivers/virtio/virtio_vdpa.c-481-\tvd_dev-\u003evdev.id.vendor = ops-\u003eget_vendor_id(vdpa);\ndrivers/virtio/virtio_vdpa.c:482:\tret = register_virtio_device(\u0026vd_dev-\u003evdev);\ndrivers/virtio/virtio_vdpa.c-483-\treg_dev = vd_dev;\n--\ndrivers/virtio/virtio_vdpa.c=499=static void virtio_vdpa_remove(struct vdpa_device vdpa)\n--\ndrivers/virtio/virtio_vdpa.c-502-\ndrivers/virtio/virtio_vdpa.c:503:\tunregister_virtio_device(\u0026vd_dev-\u003evdev);\ndrivers/virtio/virtio_vdpa.c-504-}\n--\ninclude/linux/virtio.h=195=void virtio_add_status(struct virtio_device dev, unsigned int status);\ninclude/linux/virtio.h:196:int register_virtio_device(struct virtio_device dev);\ninclude/linux/virtio.h:197:void unregister_virtio_device(struct virtio_device dev);\ninclude/linux/virtio.h-198-bool is_virtio_device(struct device dev);\n" }
11/2	2026/09/25 04:39	llm	patch-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 11770 output: 17 thoughts: 59 Thoughts: Okay, let's see. My first thought is: Exploring Dynamic VDPA Device Creation My initial focus is on the `drivers/virtio/virtio_vdpa.c` file – that's the obvious place to start digging. I'm immediately wondering about the dynamic creation of vdpa devices. Can we spin them up on the fly? That's the real key to flexible, efficient virtualization, so I'm hoping for some positive signs there. Now, let's not get ahead of ourselves. I'm trying to remember if the simulation framework uses `vdpa_sim_blk` or `vdpasim`... it's a detail, but understanding the naming conventions is important when you are in the weeds with the code. Right, let's just make sure; I'll check `vdpa_sim` to refresh my memory, and then hopefully I can get some answers about dynamic allocation.
12/2	2026/09/25 04:39	tool	grepper	0m Args: { "Expression": "vdpasim" } Results: { "Output": "\nFull output is too long, showing 500 out of 1251 lines.\nUse more precise expression if possible.\n\ndrivers/vdpa/vdpa_sim/vdpa_sim.c=41=MODULE_PARM_DESC(use_va, \"Enable/disable the device's ability to use VA\");\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-46-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:47:struct vdpasim_mm_work {\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-48-\tstruct kthread_work work;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:49:\tstruct vdpasim vdpasim;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-50-\tstruct mm_struct mm_to_bind;\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-53-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:54:static void vdpasim_mm_work_fn(struct kthread_work work)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-55-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:56:\tstruct vdpasim_mm_work mm_work =\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:57:\t\tcontainer_of(work, struct vdpasim_mm_work, work);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:58:\tstruct vdpasim vdpasim = mm_work-\u003evdpasim;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-59-\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-62-\t//TODO: should we attach the cgroup of the mm owner?\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:63:\tvdpasim-\u003emm_bound = mm_work-\u003emm_to_bind;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-64-}\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-65-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:66:static void vdpasim_worker_change_mm_sync(struct vdpasim vdpasim,\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:67:\t\t\t\t\t struct vdpasim_mm_work mm_work)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-68-{\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-70-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:71:\tkthread_init_work(work, vdpasim_mm_work_fn);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:72:\tkthread_queue_work(vdpasim-\u003eworker, work);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-73-\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-76-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:77:static struct vdpasim vdpa_to_sim(struct vdpa_device vdpa)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-78-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:79:\treturn container_of(vdpa, struct vdpasim, vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-80-}\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-81-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:82:static void vdpasim_vq_notify(struct vringh vring)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-83-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:84:\tstruct vdpasim_virtqueue vq =\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:85:\t\tcontainer_of(vring, struct vdpasim_virtqueue, vring);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-86-\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-92-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:93:static void vdpasim_queue_ready(struct vdpasim vdpasim, unsigned int idx)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-94-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:95:\tstruct vdpasim_virtqueue vq = \u0026vdpasim-\u003evqs[idx];\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-96-\tuint16_t last_avail_idx = vq-\u003evring.last_avail_idx;\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-103-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:104:\tif (use_va \u0026\u0026 vdpasim-\u003emm_bound) {\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:105:\t\tvringh_init_iotlb_va(\u0026vq-\u003evring, vdpasim-\u003efeatures, vq-\u003enum,\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-106-\t\t\t\t true, desc, avail, used);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-107-\t} else {\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:108:\t\tvringh_init_iotlb(\u0026vq-\u003evring, vdpasim-\u003efeatures, vq-\u003enum,\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-109-\t\t\t\t true, desc, avail, used);\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-120-\t Although the simple fix is to set last_used_idx at\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:121:\t * vdpasim_set_vq_state, it would be reset at vdpasim_queue_ready.\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-122-\t /\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-123-\tvq-\u003evring.last_used_idx = last_avail_idx;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:124:\tvq-\u003evring.notify = vdpasim_vq_notify;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-125-}\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-126-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:127:static void vdpasim_vq_reset(struct vdpasim vdpasim,\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:128:\t\t\t struct vdpasim_virtqueue vq)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-129-{\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-135-\tvq-\u003eprivate = NULL;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:136:\tvringh_init_iotlb(\u0026vq-\u003evring, vdpasim-\u003edev_attr.supported_features,\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-137-\t\t\t VDPASIM_QUEUE_MAX, false, NULL, NULL, NULL);\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-141-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:142:static void vdpasim_do_reset(struct vdpasim vdpasim, u32 flags)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-143-{\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-145-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:146:\tspin_lock(\u0026vdpasim-\u003eiommu_lock);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-147-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:148:\tfor (i = 0; i \u003c vdpasim-\u003edev_attr.nvqs; i++) {\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:149:\t\tvdpasim_vq_reset(vdpasim, \u0026vdpasim-\u003evqs[i]);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:150:\t\tvringh_set_iotlb(\u0026vdpasim-\u003evqs[i].vring, \u0026vdpasim-\u003eiommu[0],\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:151:\t\t\t\t \u0026vdpasim-\u003eiommu_lock);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-152-\t}\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-154-\tif (flags \u0026 VDPA_RESET_F_CLEAN_MAP) {\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:155:\t\tfor (i = 0; i \u003c vdpasim-\u003edev_attr.nas; i++) {\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:156:\t\t\tvhost_iotlb_reset(\u0026vdpasim-\u003eiommu[i]);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:157:\t\t\tvhost_iotlb_add_range(\u0026vdpasim-\u003eiommu[i], 0, ULONG_MAX,\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-158-\t\t\t\t\t 0, VHOST_MAP_RW);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:159:\t\t\tvdpasim-\u003eiommu_pt[i] = true;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-160-\t\t}\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-162-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:163:\tvdpasim-\u003erunning = false;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:164:\tvdpasim-\u003epending_kick = false;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:165:\tspin_unlock(\u0026vdpasim-\u003eiommu_lock);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-166-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:167:\tvdpasim-\u003efeatures = 0;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:168:\tvdpasim-\u003estatus = 0;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:169:\t++vdpasim-\u003egeneration;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-170-}\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-171-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:172:static const struct vdpa_config_ops vdpasim_config_ops;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:173:static const struct vdpa_config_ops vdpasim_batch_config_ops;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-174-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:175:static void vdpasim_work_fn(struct kthread_work work)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-176-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:177:\tstruct vdpasim vdpasim = container_of(work, struct vdpasim, work);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:178:\tstruct mm_struct mm = vdpasim-\u003emm_bound;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-179-\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-185-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:186:\tvdpasim-\u003edev_attr.work_fn(vdpasim);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-187-\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-193-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:194:struct vdpasim vdpasim_create(struct vdpasim_dev_attr dev_attr,\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-195-\t\t\t const struct vdpa_dev_set_config config)\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-198-\tstruct vdpa_device vdpa;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:199:\tstruct vdpasim vdpasim;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-200-\tstruct device dev;\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-216-\tif (batch_mapping)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:217:\t\tops = \u0026vdpasim_batch_config_ops;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-218-\telse\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:219:\t\tops = \u0026vdpasim_config_ops;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-220-\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-229-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:230:\tvdpasim = vdpa_to_sim(vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:231:\tvdpasim-\u003edev_attr = dev_attr;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:232:\tdev = \u0026vdpasim-\u003evdpa.dev;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-233-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:234:\tkthread_init_work(\u0026vdpasim-\u003ework, vdpasim_work_fn);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:235:\tvdpasim-\u003eworker = kthread_run_worker(0, \"vDPA sim worker: %s\",\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-236-\t\t\t\t\t\tdev_attr-\u003ename);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:237:\tif (IS_ERR(vdpasim-\u003eworker)) {\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:238:\t\tret = PTR_ERR(vdpasim-\u003eworker);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:239:\t\tvdpasim-\u003eworker = NULL;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-240-\t\tgoto err_iommu;\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-242-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:243:\tmutex_init(\u0026vdpasim-\u003emutex);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:244:\tspin_lock_init(\u0026vdpasim-\u003eiommu_lock);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-245-\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-248-\t\tgoto err_iommu;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:249:\tvdpasim-\u003evdpa.mdev = dev_attr-\u003emgmt_dev;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-250-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:251:\tvdpasim-\u003econfig = kzalloc(dev_attr-\u003econfig_size, GFP_KERNEL);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:252:\tif (!vdpasim-\u003econfig)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-253-\t\tgoto err_iommu;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-254-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:255:\tvdpasim-\u003evqs = kzalloc_objs(struct vdpasim_virtqueue, dev_attr-\u003envqs);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:256:\tif (!vdpasim-\u003evqs)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-257-\t\tgoto err_iommu;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-258-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:259:\tvdpasim-\u003eiommu = kmalloc_objs(vdpasim-\u003eiommu, vdpasim-\u003edev_attr.nas);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:260:\tif (!vdpasim-\u003eiommu)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-261-\t\tgoto err_iommu;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-262-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:263:\tvdpasim-\u003eiommu_pt = kmalloc_objs(vdpasim-\u003eiommu_pt,\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:264:\t\t\t\t\t vdpasim-\u003edev_attr.nas);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:265:\tif (!vdpasim-\u003eiommu_pt)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-266-\t\tgoto err_iommu;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-267-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:268:\tfor (i = 0; i \u003c vdpasim-\u003edev_attr.nas; i++) {\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:269:\t\tvhost_iotlb_init(\u0026vdpasim-\u003eiommu[i], max_iotlb_entries, 0);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:270:\t\tret = vhost_iotlb_add_range(\u0026vdpasim-\u003eiommu[i], 0, ULONG_MAX,\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-271-\t\t\t\t\t 0, VHOST_MAP_RW);\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-273-\t\t\tgoto err_iommu;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:274:\t\tvdpasim-\u003eiommu_pt[i] = true;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-275-\t}\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-277-\tfor (i = 0; i \u003c dev_attr-\u003envqs; i++)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:278:\t\tvringh_set_iotlb(\u0026vdpasim-\u003evqs[i].vring, \u0026vdpasim-\u003eiommu[0],\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:279:\t\t\t\t \u0026vdpasim-\u003eiommu_lock);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-280-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:281:\tvdpasim-\u003evdpa.vmap.dma_dev = dev;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-282-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:283:\treturn vdpasim;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-284-\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-289-}\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:290:EXPORT_SYMBOL_GPL(vdpasim_create);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-291-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:292:void vdpasim_schedule_work(struct vdpasim vdpasim)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-293-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:294:\tkthread_queue_work(vdpasim-\u003eworker, \u0026vdpasim-\u003ework);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-295-}\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:296:EXPORT_SYMBOL_GPL(vdpasim_schedule_work);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-297-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:298:static int vdpasim_set_vq_address(struct vdpa_device vdpa, u16 idx,\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-299-\t\t\t\t u64 desc_area, u64 driver_area,\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-301-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:302:\tstruct vdpasim vdpasim = vdpa_to_sim(vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:303:\tstruct vdpasim_virtqueue vq = \u0026vdpasim-\u003evqs[idx];\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-304-\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-311-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:312:static void vdpasim_set_vq_num(struct vdpa_device vdpa, u16 idx, u32 num)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-313-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:314:\tstruct vdpasim vdpasim = vdpa_to_sim(vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:315:\tstruct vdpasim_virtqueue vq = \u0026vdpasim-\u003evqs[idx];\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-316-\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-319-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:320:static u16 vdpasim_get_vq_size(struct vdpa_device vdpa, u16 idx)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-321-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:322:\tstruct vdpasim vdpasim = vdpa_to_sim(vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:323:\tstruct vdpasim_virtqueue vq = \u0026vdpasim-\u003evqs[idx];\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-324-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:325:\tif (vdpasim-\u003estatus \u0026 VIRTIO_CONFIG_S_DRIVER_OK)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-326-\t\treturn vq-\u003enum;\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-330-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:331:static void vdpasim_kick_vq(struct vdpa_device vdpa, u16 idx)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-332-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:333:\tstruct vdpasim vdpasim = vdpa_to_sim(vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:334:\tstruct vdpasim_virtqueue vq = \u0026vdpasim-\u003evqs[idx];\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-335-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:336:\tif (!vdpasim-\u003erunning \u0026\u0026\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:337:\t (vdpasim-\u003estatus \u0026 VIRTIO_CONFIG_S_DRIVER_OK)) {\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:338:\t\tvdpasim-\u003epending_kick = true;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-339-\t\treturn;\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-342-\tif (vq-\u003eready)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:343:\t\tvdpasim_schedule_work(vdpasim);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-344-}\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-345-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:346:static void vdpasim_set_vq_cb(struct vdpa_device vdpa, u16 idx,\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-347-\t\t\t struct vdpa_callback cb)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-348-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:349:\tstruct vdpasim vdpasim = vdpa_to_sim(vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:350:\tstruct vdpasim_virtqueue vq = \u0026vdpasim-\u003evqs[idx];\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-351-\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-355-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:356:static void vdpasim_set_vq_ready(struct vdpa_device vdpa, u16 idx, bool ready)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-357-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:358:\tstruct vdpasim vdpasim = vdpa_to_sim(vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:359:\tstruct vdpasim_virtqueue vq = \u0026vdpasim-\u003evqs[idx];\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-360-\tbool old_ready;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-361-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:362:\tmutex_lock(\u0026vdpasim-\u003emutex);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-363-\told_ready = vq-\u003eready;\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-365-\tif (vq-\u003eready \u0026\u0026 !old_ready) {\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:366:\t\tvdpasim_queue_ready(vdpasim, idx);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-367-\t}\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:368:\tmutex_unlock(\u0026vdpasim-\u003emutex);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-369-}\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-370-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:371:static bool vdpasim_get_vq_ready(struct vdpa_device vdpa, u16 idx)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-372-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:373:\tstruct vdpasim vdpasim = vdpa_to_sim(vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:374:\tstruct vdpasim_virtqueue vq = \u0026vdpasim-\u003evqs[idx];\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-375-\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-378-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:379:static int vdpasim_set_vq_state(struct vdpa_device vdpa, u16 idx,\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-380-\t\t\t\tconst struct vdpa_vq_state state)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-381-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:382:\tstruct vdpasim vdpasim = vdpa_to_sim(vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:383:\tstruct vdpasim_virtqueue vq = \u0026vdpasim-\u003evqs[idx];\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-384-\tstruct vringh vrh = \u0026vq-\u003evring;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-385-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:386:\tmutex_lock(\u0026vdpasim-\u003emutex);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-387-\tvrh-\u003elast_avail_idx = state-\u003esplit.avail_index;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:388:\tmutex_unlock(\u0026vdpasim-\u003emutex);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-389-\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-392-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:393:static int vdpasim_get_vq_state(struct vdpa_device vdpa, u16 idx,\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-394-\t\t\t\tstruct vdpa_vq_state state)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-395-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:396:\tstruct vdpasim vdpasim = vdpa_to_sim(vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:397:\tstruct vdpasim_virtqueue vq = \u0026vdpasim-\u003evqs[idx];\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-398-\tstruct vringh vrh = \u0026vq-\u003evring;\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-403-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:404:static int vdpasim_get_vq_stats(struct vdpa_device vdpa, u16 idx,\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-405-\t\t\t\tstruct sk_buff msg,\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-407-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:408:\tstruct vdpasim vdpasim = vdpa_to_sim(vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-409-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:410:\tif (vdpasim-\u003edev_attr.get_stats)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:411:\t\treturn vdpasim-\u003edev_attr.get_stats(vdpasim, idx,\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-412-\t\t\t\t\t\t msg, extack);\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-415-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:416:static u32 vdpasim_get_vq_align(struct vdpa_device vdpa)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-417-{\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-420-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:421:static u32 vdpasim_get_vq_group(struct vdpa_device vdpa, u16 idx)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-422-{\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-429-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:430:static u64 vdpasim_get_device_features(struct vdpa_device vdpa)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-431-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:432:\tstruct vdpasim vdpasim = vdpa_to_sim(vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-433-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:434:\treturn vdpasim-\u003edev_attr.supported_features;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-435-}\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-436-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:437:static u64 vdpasim_get_backend_features(const struct vdpa_device vdpa)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-438-{\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-441-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:442:static int vdpasim_set_driver_features(struct vdpa_device vdpa, u64 features)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-443-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:444:\tstruct vdpasim vdpasim = vdpa_to_sim(vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-445-\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-449-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:450:\tvdpasim-\u003efeatures = features \u0026 vdpasim-\u003edev_attr.supported_features;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-451-\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-454-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:455:static u64 vdpasim_get_driver_features(struct vdpa_device vdpa)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-456-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:457:\tstruct vdpasim vdpasim = vdpa_to_sim(vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-458-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:459:\treturn vdpasim-\u003efeatures;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-460-}\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-461-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:462:static void vdpasim_set_config_cb(struct vdpa_device vdpa,\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-463-\t\t\t\t struct vdpa_callback cb)\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-467-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:468:static u16 vdpasim_get_vq_num_max(struct vdpa_device vdpa)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-469-{\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-472-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:473:static u32 vdpasim_get_device_id(struct vdpa_device vdpa)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-474-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:475:\tstruct vdpasim vdpasim = vdpa_to_sim(vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-476-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:477:\treturn vdpasim-\u003edev_attr.id;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-478-}\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-479-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:480:static u32 vdpasim_get_vendor_id(struct vdpa_device vdpa)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-481-{\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-484-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:485:static u8 vdpasim_get_status(struct vdpa_device vdpa)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-486-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:487:\tstruct vdpasim vdpasim = vdpa_to_sim(vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-488-\tu8 status;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-489-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:490:\tmutex_lock(\u0026vdpasim-\u003emutex);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:491:\tstatus = vdpasim-\u003estatus;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:492:\tmutex_unlock(\u0026vdpasim-\u003emutex);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-493-\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-496-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:497:static void vdpasim_set_status(struct vdpa_device vdpa, u8 status)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-498-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:499:\tstruct vdpasim vdpasim = vdpa_to_sim(vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-500-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:501:\tmutex_lock(\u0026vdpasim-\u003emutex);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:502:\tvdpasim-\u003estatus = status;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:503:\tvdpasim-\u003erunning = (status \u0026 VIRTIO_CONFIG_S_DRIVER_OK) != 0;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:504:\tmutex_unlock(\u0026vdpasim-\u003emutex);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-505-}\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-506-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:507:static int vdpasim_compat_reset(struct vdpa_device vdpa, u32 flags)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-508-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:509:\tstruct vdpasim vdpasim = vdpa_to_sim(vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-510-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:511:\tmutex_lock(\u0026vdpasim-\u003emutex);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:512:\tvdpasim-\u003estatus = 0;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:513:\tvdpasim_do_reset(vdpasim, flags);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:514:\tmutex_unlock(\u0026vdpasim-\u003emutex);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-515-\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-518-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:519:static int vdpasim_reset(struct vdpa_device vdpa)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-520-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:521:\treturn vdpasim_compat_reset(vdpa, 0);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-522-}\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-523-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:524:static int vdpasim_suspend(struct vdpa_device vdpa)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-525-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:526:\tstruct vdpasim vdpasim = vdpa_to_sim(vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-527-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:528:\tmutex_lock(\u0026vdpasim-\u003emutex);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:529:\tvdpasim-\u003erunning = false;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:530:\tmutex_unlock(\u0026vdpasim-\u003emutex);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-531-\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-534-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:535:static int vdpasim_resume(struct vdpa_device vdpa)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-536-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:537:\tstruct vdpasim vdpasim = vdpa_to_sim(vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-538-\tint i;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-539-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:540:\tmutex_lock(\u0026vdpasim-\u003emutex);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:541:\tvdpasim-\u003erunning = true;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-542-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:543:\tif (vdpasim-\u003epending_kick) {\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-544-\t\t/* Process pending descriptors /\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:545:\t\tfor (i = 0; i \u003c vdpasim-\u003edev_attr.nvqs; ++i)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:546:\t\t\tvdpasim_kick_vq(vdpa, i);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-547-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:548:\t\tvdpasim-\u003epending_kick = false;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-549-\t}\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-550-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:551:\tmutex_unlock(\u0026vdpasim-\u003emutex);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-552-\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-555-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:556:static size_t vdpasim_get_config_size(struct vdpa_device vdpa)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-557-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:558:\tstruct vdpasim vdpasim = vdpa_to_sim(vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-559-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:560:\treturn vdpasim-\u003edev_attr.config_size;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-561-}\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-562-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:563:static void vdpasim_get_config(struct vdpa_device vdpa, unsigned int offset,\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-564-\t\t\t void buf, unsigned int len)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-565-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:566:\tstruct vdpasim vdpasim = vdpa_to_sim(vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-567-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:568:\tif (offset + len \u003e vdpasim-\u003edev_attr.config_size)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-569-\t\treturn;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-570-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:571:\tif (vdpasim-\u003edev_attr.get_config)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:572:\t\tvdpasim-\u003edev_attr.get_config(vdpasim, vdpasim-\u003econfig);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-573-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:574:\tmemcpy(buf, vdpasim-\u003econfig + offset, len);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-575-}\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-576-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:577:static void vdpasim_set_config(struct vdpa_device vdpa, unsigned int offset,\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-578-\t\t\t const void buf, unsigned int len)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-579-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:580:\tstruct vdpasim vdpasim = vdpa_to_sim(vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-581-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:582:\tif (offset + len \u003e vdpasim-\u003edev_attr.config_size)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-583-\t\treturn;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-584-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:585:\tmemcpy(vdpasim-\u003econfig + offset, buf, len);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-586-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:587:\tif (vdpasim-\u003edev_attr.set_config)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:588:\t\tvdpasim-\u003edev_attr.set_config(vdpasim, vdpasim-\u003econfig);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-589-}\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-590-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:591:static u32 vdpasim_get_generation(struct vdpa_device vdpa)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-592-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:593:\tstruct vdpasim vdpasim = vdpa_to_sim(vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-594-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:595:\treturn vdpasim-\u003egeneration;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-596-}\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-597-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:598:static struct vdpa_iova_range vdpasim_get_iova_range(struct vdpa_device vdpa)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-599-{\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-607-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:608:static int vdpasim_set_group_asid(struct vdpa_device vdpa, unsigned int group,\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-609-\t\t\t\t unsigned int asid)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-610-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:611:\tstruct vdpasim vdpasim = vdpa_to_sim(vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-612-\tstruct vhost_iotlb iommu;\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-614-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:615:\tiommu = \u0026vdpasim-\u003eiommu[asid];\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-616-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:617:\tmutex_lock(\u0026vdpasim-\u003emutex);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-618-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:619:\tfor (i = 0; i \u003c vdpasim-\u003edev_attr.nvqs; i++)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:620:\t\tif (vdpasim_get_vq_group(vdpa, i) == group)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:621:\t\t\tvringh_set_iotlb(\u0026vdpasim-\u003evqs[i].vring, iommu,\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:622:\t\t\t\t\t \u0026vdpasim-\u003eiommu_lock);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-623-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:624:\tmutex_unlock(\u0026vdpasim-\u003emutex);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-625-\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-628-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:629:static int vdpasim_set_map(struct vdpa_device vdpa, unsigned int asid,\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-630-\t\t\t struct vhost_iotlb iotlb)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-631-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:632:\tstruct vdpasim vdpasim = vdpa_to_sim(vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-633-\tstruct vhost_iotlb_map *map;\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-637-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:638:\tif (asid \u003e= vdpasim-\u003edev_attr.nas)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-639-\t\treturn -EINVAL;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-640-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:641:\tspin_lock(\u0026vdpasim-\u003eiommu_lock);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-642-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:643:\tiommu = \u0026vdpasim-\u003eiommu[asid];\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-644-\tvhost_iotlb_reset(iommu);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:645:\tvdpasim-\u003eiommu_pt[asid] = false;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-646-\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-653-\t}\n\n" }
13/2	2026/09/25 04:39	llm	patch-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 26456 output: 30 thoughts: 37 Thoughts: Here's a summary of my thought process, as requested: Diving into the vDPA Simulation Black Box Okay, let's get down to brass tacks. I need to understand this vDPA simulation architecture better. The first place I'm going to look, and I mean really dig into, is the `drivers/vdpa/vdpa_sim/vdpa_sim_blk.c` file. This seems like the natural starting point for the block device simulation. I suspect this will be where the core logic for emulating a vDPA block device is implemented. It's time to analyze that code with a critical eye, really understand the mechanics, and see how it all comes together.
14/2	2026/09/25 04:39	tool	grepper	0m Args: { "Expression": "vdpa_sim_blk", "PathPrefix": "drivers/vdpa" } Results: { "Output": "drivers/vdpa/vdpa_sim/Makefile=3=obj-$(CONFIG_VDPA_SIM_NET) += vdpa_sim_net.o\ndrivers/vdpa/vdpa_sim/Makefile:4:obj-$(CONFIG_VDPA_SIM_BLOCK) += vdpa_sim_blk.o\n" }
15/2	2026/09/25 04:39	llm	patch-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 26762 output: 32 thoughts: 55 Thoughts: Okay, let's break this down. Investigating the Configuration and Creation of vDPA Devices Right, so I'm looking at `CONFIG_VDPA_SIM_BLOCK`. This likely relates to a simulated vDPA block device, which is interesting, but I need to figure out the fundamental mechanics of how these vDPA devices are created in the first place. My immediate question is whether we're dealing with a netlink-based approach for device instantiation. Specifically, is the kernel using generic netlink (`GENL_VDPA`, or something similar) to handle the creation and management of these virtual data path acceleration (vDPA) devices? To answer that, I need to dive into the core implementation. The logical place to start digging is `drivers/vdpa/vdpa.c`. That should give me the core logic related to vDPA handling, device registration, and potentially, the netlink interface if one exists. Let's see what's in there.
16/2	2026/09/25 04:39	tool	grepper	0m Args: { "Expression": "VDPA_CMD_DEV_NEW", "PathPrefix": "drivers/vdpa" } Results: { "Output": "drivers/vdpa/vdpa.c=703=vdpa_dev_fill(struct vdpa_device vdev, struct sk_buff msg, u32 portid, u32 seq,\n--\ndrivers/vdpa/vdpa.c-712-\ndrivers/vdpa/vdpa.c:713:\thdr = genlmsg_put(msg, portid, seq, \u0026vdpa_nl_family, flags, VDPA_CMD_DEV_NEW);\ndrivers/vdpa/vdpa.c-714-\tif (!hdr)\n--\ndrivers/vdpa/vdpa.c=1507=static const struct genl_ops vdpa_nl_ops[] = {\n--\ndrivers/vdpa/vdpa.c-1513-\t{\ndrivers/vdpa/vdpa.c:1514:\t\t.cmd = VDPA_CMD_DEV_NEW,\ndrivers/vdpa/vdpa.c-1515-\t\t.doit = vdpa_nl_cmd_dev_add_set_doit,\n" }
17/2	2026/09/25 04:39	llm	patch-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 27328 output: 26 thoughts: 73 Thoughts: Okay, let's break this down. Initial Assessment of VDPA Device Creation Right, so I'm thinking about VDPA devices and how they're brought into existence. The gist is, we can create these things using the generic netlink interface, specifically with that `VDPA_CMD_DEV_NEW` command. That seems like the logical starting point, and it rings true with my understanding of netlink's role in device management in this context. Now, the natural follow-up is, what actually happens after that? When we invoke `VDPA_CMD_DEV_NEW`, does the system then automatically, or via some driver-level magic, bind this newly created device to `virtio_vdpa`? That's the question I need to answer. I suspect the answer will involve either registration with the virtio driver or some form of binding process. The most likely locations for this are going to be in the device registration or probing logic. To get the lowdown, I should probably dive into the source code. Let's see...I'll start with `drivers/vdpa/vdpa.c` since that's the more general VDPA location. If that doesn't yield immediate answers, I'll then move onto `drivers/virtio/virtio_vdpa.c`. I'm expecting to find the key details regarding the creation process and any association made between the generic VDPA framework and the virtio backend. Hopefully, one of those files will have the answers.
18/2	2026/09/25 04:39	tool	grepper	0m Args: { "Expression": "virtio_vdpa", "PathPrefix": "drivers" } Results: { "Output": "drivers/virtio/Makefile=12=obj-$(CONFIG_VIRTIO_INPUT) += virtio_input.o\ndrivers/virtio/Makefile:13:obj-$(CONFIG_VIRTIO_VDPA) += virtio_vdpa.o\ndrivers/virtio/Makefile-14-obj-$(CONFIG_VIRTIO_MEM) += virtio_mem.o\n--\ndrivers/virtio/virtio_vdpa.c-26-\ndrivers/virtio/virtio_vdpa.c:27:struct virtio_vdpa_device {\ndrivers/virtio/virtio_vdpa.c-28-\tstruct virtio_device vdev;\n--\ndrivers/virtio/virtio_vdpa.c-32-\ndrivers/virtio/virtio_vdpa.c:33:static inline struct virtio_vdpa_device \ndrivers/virtio/virtio_vdpa.c:34:to_virtio_vdpa_device(struct virtio_device dev)\ndrivers/virtio/virtio_vdpa.c-35-{\ndrivers/virtio/virtio_vdpa.c:36:\treturn container_of(dev, struct virtio_vdpa_device, vdev);\ndrivers/virtio/virtio_vdpa.c-37-}\n--\ndrivers/virtio/virtio_vdpa.c=39=static struct vdpa_device vd_get_vdpa(struct virtio_device vdev)\ndrivers/virtio/virtio_vdpa.c-40-{\ndrivers/virtio/virtio_vdpa.c:41:\treturn to_virtio_vdpa_device(vdev)-\u003evdpa;\ndrivers/virtio/virtio_vdpa.c-42-}\ndrivers/virtio/virtio_vdpa.c-43-\ndrivers/virtio/virtio_vdpa.c:44:static void virtio_vdpa_get(struct virtio_device vdev, unsigned int offset,\ndrivers/virtio/virtio_vdpa.c-45-\t\t\t void buf, unsigned int len)\n--\ndrivers/virtio/virtio_vdpa.c-51-\ndrivers/virtio/virtio_vdpa.c:52:static void virtio_vdpa_set(struct virtio_device vdev, unsigned int offset,\ndrivers/virtio/virtio_vdpa.c-53-\t\t\t const void buf, unsigned int len)\n--\ndrivers/virtio/virtio_vdpa.c-59-\ndrivers/virtio/virtio_vdpa.c:60:static u32 virtio_vdpa_generation(struct virtio_device vdev)\ndrivers/virtio/virtio_vdpa.c-61-{\n--\ndrivers/virtio/virtio_vdpa.c-70-\ndrivers/virtio/virtio_vdpa.c:71:static u8 virtio_vdpa_get_status(struct virtio_device vdev)\ndrivers/virtio/virtio_vdpa.c-72-{\n--\ndrivers/virtio/virtio_vdpa.c-78-\ndrivers/virtio/virtio_vdpa.c:79:static void virtio_vdpa_set_status(struct virtio_device vdev, u8 status)\ndrivers/virtio/virtio_vdpa.c-80-{\n--\ndrivers/virtio/virtio_vdpa.c-85-\ndrivers/virtio/virtio_vdpa.c:86:static void virtio_vdpa_reset(struct virtio_device vdev)\ndrivers/virtio/virtio_vdpa.c-87-{\n--\ndrivers/virtio/virtio_vdpa.c-92-\ndrivers/virtio/virtio_vdpa.c:93:static bool virtio_vdpa_notify(struct virtqueue vq)\ndrivers/virtio/virtio_vdpa.c-94-{\n--\ndrivers/virtio/virtio_vdpa.c-102-\ndrivers/virtio/virtio_vdpa.c:103:static bool virtio_vdpa_notify_with_data(struct virtqueue vq)\ndrivers/virtio/virtio_vdpa.c-104-{\n--\ndrivers/virtio/virtio_vdpa.c-113-\ndrivers/virtio/virtio_vdpa.c:114:static irqreturn_t virtio_vdpa_config_cb(void private)\ndrivers/virtio/virtio_vdpa.c-115-{\ndrivers/virtio/virtio_vdpa.c:116:\tstruct virtio_vdpa_device vd_dev = private;\ndrivers/virtio/virtio_vdpa.c-117-\n--\ndrivers/virtio/virtio_vdpa.c-122-\ndrivers/virtio/virtio_vdpa.c:123:static irqreturn_t virtio_vdpa_virtqueue_cb(void private)\ndrivers/virtio/virtio_vdpa.c-124-{\n--\ndrivers/virtio/virtio_vdpa.c=130=static struct virtqueue \ndrivers/virtio/virtio_vdpa.c:131:virtio_vdpa_setup_vq(struct virtio_device vdev, unsigned int index,\ndrivers/virtio/virtio_vdpa.c-132-\t\t void (callback)(struct virtqueue vq),\n--\ndrivers/virtio/virtio_vdpa.c-136-\tconst struct vdpa_config_ops ops = vdpa-\u003econfig;\ndrivers/virtio/virtio_vdpa.c:137:\tbool (notify)(struct virtqueue vq) = virtio_vdpa_notify;\ndrivers/virtio/virtio_vdpa.c-138-\tstruct vdpa_callback cb;\n--\ndrivers/virtio/virtio_vdpa.c-156-\t\tif (ops-\u003ekick_vq_with_data)\ndrivers/virtio/virtio_vdpa.c:157:\t\t\tnotify = virtio_vdpa_notify_with_data;\ndrivers/virtio/virtio_vdpa.c-158-\t\telse\n--\ndrivers/virtio/virtio_vdpa.c-202-\t/* Setup virtqueue callback /\ndrivers/virtio/virtio_vdpa.c:203:\tcb.callback = callback ? virtio_vdpa_virtqueue_cb : NULL;\ndrivers/virtio/virtio_vdpa.c-204-\tcb.private = vq;\n--\ndrivers/virtio/virtio_vdpa.c-245-\ndrivers/virtio/virtio_vdpa.c:246:static void virtio_vdpa_del_vq(struct virtqueue vq)\ndrivers/virtio/virtio_vdpa.c-247-{\ndrivers/virtio/virtio_vdpa.c:248:\tstruct virtio_vdpa_device vd_dev = to_virtio_vdpa_device(vq-\u003evdev);\ndrivers/virtio/virtio_vdpa.c-249-\tstruct vdpa_device vdpa = vd_dev-\u003evdpa;\n--\ndrivers/virtio/virtio_vdpa.c-258-\ndrivers/virtio/virtio_vdpa.c:259:static void virtio_vdpa_del_vqs(struct virtio_device vdev)\ndrivers/virtio/virtio_vdpa.c-260-{\n--\ndrivers/virtio/virtio_vdpa.c-263-\tlist_for_each_entry_safe(vq, n, \u0026vdev-\u003evqs, list)\ndrivers/virtio/virtio_vdpa.c:264:\t\tvirtio_vdpa_del_vq(vq);\ndrivers/virtio/virtio_vdpa.c-265-}\n--\ndrivers/virtio/virtio_vdpa.c=274=create_affinity_masks(unsigned int nvecs, struct irq_affinity affd)\n--\ndrivers/virtio/virtio_vdpa.c-327-\ndrivers/virtio/virtio_vdpa.c:328:static int virtio_vdpa_find_vqs(struct virtio_device vdev, unsigned int nvqs,\ndrivers/virtio/virtio_vdpa.c-329-\t\t\t\tstruct virtqueue vqs[],\n--\ndrivers/virtio/virtio_vdpa.c-332-{\ndrivers/virtio/virtio_vdpa.c:333:\tstruct virtio_vdpa_device vd_dev = to_virtio_vdpa_device(vdev);\ndrivers/virtio/virtio_vdpa.c-334-\tstruct vdpa_device vdpa = vd_get_vdpa(vdev);\n--\ndrivers/virtio/virtio_vdpa.c-354-\ndrivers/virtio/virtio_vdpa.c:355:\t\tvqs[i] = virtio_vdpa_setup_vq(vdev, queue_idx, vqi-\u003ecallback,\ndrivers/virtio/virtio_vdpa.c-356-\t\t\t\t\t vqi-\u003ename, vqi-\u003ectx);\n--\ndrivers/virtio/virtio_vdpa.c-366-\ndrivers/virtio/virtio_vdpa.c:367:\tcb.callback = virtio_vdpa_config_cb;\ndrivers/virtio/virtio_vdpa.c-368-\tcb.private = vd_dev;\n--\ndrivers/virtio/virtio_vdpa.c-375-err_setup_vq:\ndrivers/virtio/virtio_vdpa.c:376:\tvirtio_vdpa_del_vqs(vdev);\ndrivers/virtio/virtio_vdpa.c-377-\tif (has_affinity)\n--\ndrivers/virtio/virtio_vdpa.c-381-\ndrivers/virtio/virtio_vdpa.c:382:static u64 virtio_vdpa_get_features(struct virtio_device vdev)\ndrivers/virtio/virtio_vdpa.c-383-{\n--\ndrivers/virtio/virtio_vdpa.c-389-\ndrivers/virtio/virtio_vdpa.c:390:static int virtio_vdpa_finalize_features(struct virtio_device vdev)\ndrivers/virtio/virtio_vdpa.c-391-{\n--\ndrivers/virtio/virtio_vdpa.c-399-\ndrivers/virtio/virtio_vdpa.c:400:static const char virtio_vdpa_bus_name(struct virtio_device vdev)\ndrivers/virtio/virtio_vdpa.c-401-{\ndrivers/virtio/virtio_vdpa.c:402:\tstruct virtio_vdpa_device vd_dev = to_virtio_vdpa_device(vdev);\ndrivers/virtio/virtio_vdpa.c-403-\tstruct vdpa_device vdpa = vd_dev-\u003evdpa;\n--\ndrivers/virtio/virtio_vdpa.c-407-\ndrivers/virtio/virtio_vdpa.c:408:static int virtio_vdpa_set_vq_affinity(struct virtqueue vq,\ndrivers/virtio/virtio_vdpa.c-409-\t\t\t\t const struct cpumask cpu_mask)\ndrivers/virtio/virtio_vdpa.c-410-{\ndrivers/virtio/virtio_vdpa.c:411:\tstruct virtio_vdpa_device vd_dev = to_virtio_vdpa_device(vq-\u003evdev);\ndrivers/virtio/virtio_vdpa.c-412-\tstruct vdpa_device vdpa = vd_dev-\u003evdpa;\n--\ndrivers/virtio/virtio_vdpa.c=422=static const struct cpumask \ndrivers/virtio/virtio_vdpa.c:423:virtio_vdpa_get_vq_affinity(struct virtio_device vdev, int index)\ndrivers/virtio/virtio_vdpa.c-424-{\n--\ndrivers/virtio/virtio_vdpa.c-433-\ndrivers/virtio/virtio_vdpa.c:434:static const struct virtio_config_ops virtio_vdpa_config_ops = {\ndrivers/virtio/virtio_vdpa.c:435:\t.get\t\t= virtio_vdpa_get,\ndrivers/virtio/virtio_vdpa.c:436:\t.set\t\t= virtio_vdpa_set,\ndrivers/virtio/virtio_vdpa.c:437:\t.generation\t= virtio_vdpa_generation,\ndrivers/virtio/virtio_vdpa.c:438:\t.get_status\t= virtio_vdpa_get_status,\ndrivers/virtio/virtio_vdpa.c:439:\t.set_status\t= virtio_vdpa_set_status,\ndrivers/virtio/virtio_vdpa.c:440:\t.reset\t\t= virtio_vdpa_reset,\ndrivers/virtio/virtio_vdpa.c:441:\t.find_vqs\t= virtio_vdpa_find_vqs,\ndrivers/virtio/virtio_vdpa.c:442:\t.del_vqs\t= virtio_vdpa_del_vqs,\ndrivers/virtio/virtio_vdpa.c:443:\t.get_features\t= virtio_vdpa_get_features,\ndrivers/virtio/virtio_vdpa.c:444:\t.finalize_features = virtio_vdpa_finalize_features,\ndrivers/virtio/virtio_vdpa.c:445:\t.bus_name\t= virtio_vdpa_bus_name,\ndrivers/virtio/virtio_vdpa.c:446:\t.set_vq_affinity = virtio_vdpa_set_vq_affinity,\ndrivers/virtio/virtio_vdpa.c:447:\t.get_vq_affinity = virtio_vdpa_get_vq_affinity,\ndrivers/virtio/virtio_vdpa.c-448-};\ndrivers/virtio/virtio_vdpa.c-449-\ndrivers/virtio/virtio_vdpa.c:450:static void virtio_vdpa_release_dev(struct device _d)\ndrivers/virtio/virtio_vdpa.c-451-{\n--\ndrivers/virtio/virtio_vdpa.c-453-\t container_of(_d, struct virtio_device, dev);\ndrivers/virtio/virtio_vdpa.c:454:\tstruct virtio_vdpa_device vd_dev =\ndrivers/virtio/virtio_vdpa.c:455:\t container_of(vdev, struct virtio_vdpa_device, vdev);\ndrivers/virtio/virtio_vdpa.c-456-\n--\ndrivers/virtio/virtio_vdpa.c-459-\ndrivers/virtio/virtio_vdpa.c:460:static int virtio_vdpa_probe(struct vdpa_device vdpa)\ndrivers/virtio/virtio_vdpa.c-461-{\ndrivers/virtio/virtio_vdpa.c-462-\tconst struct vdpa_config_ops ops = vdpa-\u003econfig;\ndrivers/virtio/virtio_vdpa.c:463:\tstruct virtio_vdpa_device vd_dev, reg_dev = NULL;\ndrivers/virtio/virtio_vdpa.c-464-\tint ret = -EINVAL;\n--\ndrivers/virtio/virtio_vdpa.c-471-\t\t\t\t vdpa_get_map(vdpa).dma_dev;\ndrivers/virtio/virtio_vdpa.c:472:\tvd_dev-\u003evdev.dev.release = virtio_vdpa_release_dev;\ndrivers/virtio/virtio_vdpa.c:473:\tvd_dev-\u003evdev.config = \u0026virtio_vdpa_config_ops;\ndrivers/virtio/virtio_vdpa.c-474-\tvd_dev-\u003evdev.map = vdpa-\u003emap;\n--\ndrivers/virtio/virtio_vdpa.c-498-\ndrivers/virtio/virtio_vdpa.c:499:static void virtio_vdpa_remove(struct vdpa_device vdpa)\ndrivers/virtio/virtio_vdpa.c-500-{\ndrivers/virtio/virtio_vdpa.c:501:\tstruct virtio_vdpa_device vd_dev = vdpa_get_drvdata(vdpa);\ndrivers/virtio/virtio_vdpa.c-502-\n--\ndrivers/virtio/virtio_vdpa.c-505-\ndrivers/virtio/virtio_vdpa.c:506:static struct vdpa_driver virtio_vdpa_driver = {\ndrivers/virtio/virtio_vdpa.c-507-\t.driver = {\ndrivers/virtio/virtio_vdpa.c:508:\t\t.name\t= \"virtio_vdpa\",\ndrivers/virtio/virtio_vdpa.c-509-\t},\ndrivers/virtio/virtio_vdpa.c:510:\t.probe\t= virtio_vdpa_probe,\ndrivers/virtio/virtio_vdpa.c:511:\t.remove = virtio_vdpa_remove,\ndrivers/virtio/virtio_vdpa.c-512-};\ndrivers/virtio/virtio_vdpa.c-513-\ndrivers/virtio/virtio_vdpa.c:514:module_vdpa_driver(virtio_vdpa_driver);\ndrivers/virtio/virtio_vdpa.c-515-\n" }
19/2	2026/09/25 04:39	llm	patch-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 32253 output: 39 thoughts: 1884 Thoughts: Analysis of virtio_blk Driver Bug and Reachability for Fuzzing Okay, so looking at this code, it appears `vdpa_sim_blk` creates a vDPA device that simulates a virtio-blk device. When a vdpa device is managed by `virtio_vdpa`, `virtio_vdpa_probe` calls `register_virtio_device(&vd_dev->vdev)`. That, in turn, registers the device on the `virtio_bus`. When that device gets matched to `virtio_blk`, `virtblk_probe` is called. The instructions specifically state that drivers accessible via virtual buses like virtio are fair game. I'm starting to zero in on this `virtblk_probe` function. I need to figure out if there's a scenario where it can fail and hit the `out_cleanup_disk` path. Looking closely at `virtblk_probe`, I see `device_add_disk()` is called, and if that fails, we jump to `out_cleanup_disk`. I also notice a commit that adds `virtio_reset_device(vdev)` before `put_disk(vblk->disk)`. Aha! Now I see the light, that commit fixed a bug related to `device_add_disk` failing! Before the patch, `virtio_device_ready(vdev)` was called, marking the device as `DRIVER_OK`, potentially with active interrupts/callbacks/virtqueues. If `device_add_disk` failed after that, the device would be partially set up, but the cleanup path didn't stop the virtqueues or clear `DRIVER_OK`! Without the `virtio_reset_device`, this could lead to issues. Now, the crucial question is whether this code path, specifically the error handling in `virtblk_probe`, is actually reachable. I have to ensure this doesn't fall into the negative criteria listed. 1. This isn't a non-kernel, non-executable change. It's C code within the `virtio_blk` driver. 2. It's not structurally unreachable hardware. Virtio is explicitly mentioned as reachable via virtual buses within the positive criteria. 3. This isn't a driver teardown callback (.remove, .shutdown, pci_unregister_driver) executed only during physical PCI hot-unplug or manual sysfs driver unbinding. This is error handling during probe, not teardown. So, to be clear, the error cleanup in `virtblk_probe` is reachable. How might `device_add_disk` fail? Well, fault injection is a big one. Also, memory allocation failures, duplicate sysfs names, or failures if `CONFIG_BLK_DEV_ZONED` is enabled and `blk_revalidate_disk_zones()` fails. Syzkaller is known to use fault injection, especially during driver probe! I should look for those. Can syzkaller actually fuzz `virtio_blk`? Can it create virtio_blk devices or vdpa devices? Yes! Through vdpa netlink (`VDPA_CMD_DEV_NEW`) to instantiate a `vdpa_sim_blk` device and bind `virtio_vdpa` to it, through fault injection on boot/module loading, or by using vdpa! Also, the prompt does not exclude userspace interaction with the driver via the driver core sysfs. In short: Virtio is a reachable virtual bus, `virtio_blk` is the canonical virtio block driver, and the specific code path that this patch fixes is reachable through various scenarios (particularly error handling with tools like Syzkaller). Finally, I will check the area in `drivers/block/virtio_blk.c` around `virtblk_probe` for focus symbols to be considered.
20/2	2026/09/25 04:39	tool	read-file	0m Args: { "File": "drivers/block/virtio_blk.c", "FirstLine": 1435, "LineCount": 90 } Results: { "Contents": "1435:\t\treturn 0;\n1436:\t}\n1437:\t\n1438:\tstatic int virtblk_probe(struct virtio_device vdev)\n1439:\t{\n1440:\t\tstruct virtio_blk vblk;\n1441:\t\tstruct queue_limits lim = {\n1442:\t\t\t.features\t\t= BLK_FEAT_ROTATIONAL,\n1443:\t\t\t.logical_block_size\t= SECTOR_SIZE,\n1444:\t\t};\n1445:\t\tint err, index;\n1446:\t\tunsigned int queue_depth;\n1447:\t\n1448:\t\tif (!vdev-\u003econfig-\u003eget) {\n1449:\t\t\tdev_err(\u0026vdev-\u003edev, \"%s failure: config access disabled\\n\",\n1450:\t\t\t\t__func__);\n1451:\t\t\treturn -EINVAL;\n1452:\t\t}\n1453:\t\n1454:\t\terr = ida_alloc_range(\u0026vd_index_ida, 0,\n1455:\t\t\t\t minor_to_index(1 \u003c\u003c MINORBITS) - 1, GFP_KERNEL);\n1456:\t\tif (err \u003c 0)\n1457:\t\t\tgoto out;\n1458:\t\tindex = err;\n1459:\t\n1460:\t\tvdev-\u003epriv = vblk = kmalloc_obj(vblk);\n1461:\t\tif (!vblk) {\n1462:\t\t\terr = -ENOMEM;\n1463:\t\t\tgoto out_free_index;\n1464:\t\t}\n1465:\t\n1466:\t\tmutex_init(\u0026vblk-\u003evdev_mutex);\n1467:\t\n1468:\t\tvblk-\u003evdev = vdev;\n1469:\t\n1470:\t\tINIT_WORK(\u0026vblk-\u003econfig_work, virtblk_config_changed_work);\n1471:\t\n1472:\t\terr = init_vq(vblk);\n1473:\t\tif (err)\n1474:\t\t\tgoto out_free_vblk;\n1475:\t\n1476:\t\t/ Default queue sizing is to fill the ring. /\n1477:\t\tif (!virtblk_queue_depth) {\n1478:\t\t\tqueue_depth = vblk-\u003evqs[0].vq-\u003enum_free;\n1479:\t\t\t/ ... but without indirect descs, we use 2 descs per req /\n1480:\t\t\tif (!virtio_has_feature(vdev, VIRTIO_RING_F_INDIRECT_DESC))\n1481:\t\t\t\tqueue_depth /= 2;\n1482:\t\t} else {\n1483:\t\t\tqueue_depth = virtblk_queue_depth;\n1484:\t\t}\n1485:\t\n1486:\t\tmemset(\u0026vblk-\u003etag_set, 0, sizeof(vblk-\u003etag_set));\n1487:\t\tvblk-\u003etag_set.ops = \u0026virtio_mq_ops;\n1488:\t\tvblk-\u003etag_set.queue_depth = queue_depth;\n1489:\t\tvblk-\u003etag_set.numa_node = NUMA_NO_NODE;\n1490:\t\tvblk-\u003etag_set.cmd_size =\n1491:\t\t\tsizeof(struct virtblk_req) +\n1492:\t\t\tsizeof(struct scatterlist) VIRTIO_BLK_INLINE_SG_CNT;\n1493:\t\tvblk-\u003etag_set.driver_data = vblk;\n1494:\t\tvblk-\u003etag_set.nr_hw_queues = vblk-\u003enum_vqs;\n1495:\t\tvblk-\u003etag_set.nr_maps = 1;\n1496:\t\tif (vblk-\u003eio_queues[HCTX_TYPE_POLL])\n1497:\t\t\tvblk-\u003etag_set.nr_maps = 3;\n1498:\t\n1499:\t\terr = blk_mq_alloc_tag_set(\u0026vblk-\u003etag_set);\n1500:\t\tif (err)\n1501:\t\t\tgoto out_free_vq;\n1502:\t\n1503:\t\terr = virtblk_read_limits(vblk, \u0026lim);\n1504:\t\tif (err)\n1505:\t\t\tgoto out_free_tags;\n1506:\t\n1507:\t\tif (virtblk_get_cache_mode(vdev))\n1508:\t\t\tlim.features \|= BLK_FEAT_WRITE_CACHE;\n1509:\t\n1510:\t\tvblk-\u003edisk = blk_mq_alloc_disk(\u0026vblk-\u003etag_set, \u0026lim, vblk);\n1511:\t\tif (IS_ERR(vblk-\u003edisk)) {\n1512:\t\t\terr = PTR_ERR(vblk-\u003edisk);\n1513:\t\t\tgoto out_free_tags;\n1514:\t\t}\n1515:\t\n1516:\t\tvirtblk_name_format(\"vd\", index, vblk-\u003edisk-\u003edisk_name, DISK_NAME_LEN);\n1517:\t\n1518:\t\tvblk-\u003edisk-\u003emajor = major;\n1519:\t\tvblk-\u003edisk-\u003efirst_minor = index_to_minor(index);\n1520:\t\tvblk-\u003edisk-\u003eminors = 1 \u003c\u003c PART_BITS;\n1521:\t\tvblk-\u003edisk-\u003eprivate_data = vblk;\n1522:\t\tvblk-\u003edisk-\u003efops = \u0026virtblk_fops;\n1523:\t\tvblk-\u003eindex = index;\n1524:\t\n" }
21/2	2026/09/25 04:39	llm	patch-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 36473 output: 29 thoughts: 25 Thoughts: Okay, here's my take on those thoughts, tailored for an expert audience: Diving into the Virtio Block Kconfig Alright, time to get my hands dirty with the `virtio_blk` Kconfig. I need to understand its configuration. First things first, I need to pinpoint exactly where `CONFIG_VIRTIO_BLK` is defined within the Kconfig files. Knowing the definition is crucial for tracing its dependencies, possible default settings, and potential build options. Gotta start there.
22/2	2026/09/25 04:39	tool	grepper	0m Args: { "Expression": "config VIRTIO_BLK", "PathPrefix": "drivers/block" } Results: { "Output": "drivers/block/Kconfig=286=config XEN_BLKDEV_BACKEND\n--\ndrivers/block/Kconfig-306-\ndrivers/block/Kconfig:307:config VIRTIO_BLK\ndrivers/block/Kconfig-308-\ttristate \"Virtio block driver\"\n" }
23/2	2026/09/25 04:39	llm	patch-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 36723 output: 34 thoughts: 19 Thoughts: Okay, let's dive into this. Here's my thought process on the matter: Analyzing Block Driver Configuration in Kconfig Alright, time to get my hands dirty. I'm going to jump straight into the heart of the matter – the `drivers/block/Kconfig` file. Specifically, I'm focusing around line 307. I know this file is where the configuration options for block device drivers are defined, so I'm expecting to find some interesting logic there. I'm hoping to get a clearer picture of how specific drivers are selected, what dependencies they have, and perhaps even some hints about the overall design philosophy regarding block device handling in this kernel version. I'm keen to see the structure, conditionals, and any macros that are employed to determine which drivers are compiled into the image and how they relate to the underlying hardware.
24/2	2026/09/25 04:39	tool	read-file	0m Args: { "File": "drivers/block/Kconfig", "FirstLine": 305, "LineCount": 20 } Results: { "Contents": " 305:\t\n 306:\t\n 307:\tconfig VIRTIO_BLK\n 308:\t\ttristate \"Virtio block driver\"\n 309:\t\tdepends on VIRTIO\n 310:\t\tselect SG_POOL\n 311:\t\thelp\n 312:\t\t This is the virtual block driver for virtio. It can be used with\n 313:\t QEMU based VMMs (like KVM or Xen). Say Y or M.\n 314:\t\n 315:\tconfig BLK_DEV_RBD\n 316:\t\ttristate \"Rados block device (RBD)\"\n 317:\t\tdepends on INET \u0026\u0026 BLOCK\n 318:\t\tselect CEPH_LIB\n 319:\t\thelp\n 320:\t\t Say Y here if you want include the Rados block device, which stripes\n 321:\t\t a block device over objects stored in the Ceph distributed object\n 322:\t\t store.\n 323:\t\n 324:\t\t More information at http://ceph.newdream.net/.\n" }
25/2	2026/09/25 04:39	llm	patch-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 37250 output: 31 thoughts: 286 Thoughts: Analyzing Virtio Block Configuration Okay, so I'm looking at `CONFIG_VIRTIO_BLK`, and it's clear that it depends on `CONFIG_VIRTIO`. That's the starting point. Now, the key here is to see if either of them, `VIRTIO_BLK` or `VIRTIO`, has any other dependencies that I need to be aware of. I'll need to double-check the `drivers/block/Kconfig` file. Right, I see, `depends on VIRTIO` again. That confirms the initial dependency. And `select SG_POOL`, that's noted. Now, let's cast a wider net. I should identify all the related configs. Let's make sure I'm not missing anything. I've got `VIRTIO` and `VIRTIO_BLK` already, and then I see `BLK_DEV_ZONED` might be relevant since zoned check is right above `out_cleanup_disk`. Looking at the code: `if (IS_ENABLED(CONFIG_BLK_DEV_ZONED) && (lim.features & BLK_FEAT_ZONED))`. I should make a note of this. Ah, and I almost forgot about `VIRTIO_VDPA` and `VDPA_SIM_BLOCK`. Those enable the dynamic testing of virtio-blk via the vDPA simulator. Good, so the takeaway here is, for enabling, it's `VIRTIO_BLK`, and `VIRTIO`, obviously. Hold on, I need to check something important. I'm wondering if `virtblk_probe` is something I should include in `FocusSymbols`. And I'm also wondering if `virtio_reset_device` should be considered too. Wait a second! I'm forgetting something. `virtio_reset_device` is in `drivers/virtio/virtio.c`. Let me refresh my memory and check what `virtio_reset_device` actually does.
26/2	2026/09/25 04:39	tool	grepper	0m Args: { "Expression": "void virtio_reset_device", "PathPrefix": "drivers/virtio" } Results: { "Output": "drivers/virtio/virtio.c=204=static int virtio_features_ok(struct virtio_device dev)\n--\ndrivers/virtio/virtio.c-252- /\ndrivers/virtio/virtio.c:253:void virtio_reset_device(struct virtio_device dev)\ndrivers/virtio/virtio.c-254-{\n" }
27/2	2026/09/25 04:39	llm	patch-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 38114 output: 153 thoughts: 560 Thoughts: My Analysis of the Fuzzing Strategy Okay, let's break this down from a fuzzing perspective. `virtio_reset_device` is the generic reset function for all virtio devices – we know that. Now, the key is understanding how to apply the "WorthFuzzing=true" principle and focus our fuzzer effectively, per Section 4's guidance. I've been tasked with analyzing this patch, and I need to determine the right approach. The critical function modified by this patch is `virtblk_probe`. Is it ubiquitous? No, thankfully, it's specific to the virtio_blk driver's probing process. That's a good start. But is it a non-static symbol? I have to confirm that `virtblk_probe` is a distinct symbol in vmlinux, and it seems like it is, since it's defined as `static int virtblk_probe(struct virtio_device vdev)` in `drivers/block/virtio_blk.c`. In the Linux kernel, static functions in `.c` files have symbol addresses in `kallsyms` and `vmlinux`, unless inlined. Because it's a probe callback pointer, assigned to `.probe = virtblk_probe` in `virtio_driver`, it cannot* be inlined. So, yes, it's a distinct symbol. Now, let's verify that the patch makes sense in the larger context. Looking at the code snippet, I see that the patch invokes `virtio_reset_device(vdev)` within `virtblk_probe`'s error cleanup path, specifically if `device_add_disk()` or `blk_revalidate_disk_zones()` fails. This implies that the device had been made ready through `virtio_device_ready(vdev)`. So, this `virtio_reset_device` call is there to ensure the virtio device is properly reset after being enabled, in the case of a disk initialization failure. Based on this analysis, the reasoning is sound. The patch addresses a missing error-cleanup device reset (`virtio_reset_device`) within `virtblk_probe()` when disk initialization fails, after the device has been readied. Virtio block devices are common in virtualized environments (QEMU, vDPA/virtio-vdpa), and can be probed at boot or dynamically, making this error path reachable under fault injection or device setup failure. Therefore, the setup for `WorthFuzzing=true` is valid. The `FocusSymbols` should be set to `["virtblk_probe"]`. The `EnableConfigs` should include `["VIRTIO_BLK", "VIRTIO"]`. I'm confident in my analysis. It's time to call `set-results`.
28/2	2026/09/25 04:39	tool	set-results	0m Args: { "EnableConfigs": [ "VIRTIO_BLK", "VIRTIO" ], "FocusSymbols": [ "virtblk_probe" ], "Reasoning": "The patch modifies the probe error handling path in the virtio_blk driver, adding a call to virtio_reset_device() in virtblk_probe() if blk_revalidate_disk_zones() or device_add_disk() fails after virtio_device_ready() has been called. Virtio drivers operate on virtual devices accessible in standard QEMU environments (and dynamically via vDPA simulation), and this error path is reachable during device initialization under error conditions or fault injection.", "WorthFuzzing": true } Results: { "EnableConfigs": [ "VIRTIO_BLK", "VIRTIO" ], "FocusSymbols": [ "virtblk_probe" ], "Reasoning": "The patch modifies the probe error handling path in the virtio_blk driver, adding a call to virtio_reset_device() in virtblk_probe() if blk_revalidate_disk_zones() or device_add_disk() fails after virtio_device_ready() has been called. Virtio drivers operate on virtual devices accessible in standard QEMU environments (and dynamically via vDPA simulation), and this error path is reachable during device initialization under error conditions or fault injection.", "WorthFuzzing": true }
29/1	2026/09/25 04:39	action	If	0m Args: { "WorthFuzzing": true } Results: null
30/2	2026/09/25 04:39	agent	kmsan-evaluator	0m Model: core Args: null Results: { "KMSANReasoning": "The patch inserts a call to virtio_reset_device(vdev) in the error cleanup path (out_cleanup_disk) of virtblk_probe(). When probe fails after virtio_device_ready() was already invoked, resetting the device stops virtqueue operations and hardware interrupts before freeing the tag set, virtqueues, and disk structures.\n\nThis change exclusively addresses device teardown order and avoids potential use-after-free or race conditions where host/device accesses freed structures, which falls squarely within the scope of KASAN. The patch does not touch, allocate, or read any uninitialized memory, does not alter data boundaries or control flow based on uninitialized fields, and does not leak kernel memory to user space. Therefore, a dedicated KMSAN fuzzing session is not warranted.", "NeedsKMSAN": false } Instruction: You are an expert Linux kernel security engineer specializing in kernel memory error detectors (KASAN and KMSAN). Your job is to review the provided patch series and determine if the code changes justify spawning a dedicated KMSAN (KernelMemorySanitizer) fuzzing session in addition to standard KASAN fuzzing. CRITICAL DISTINCTION BETWEEN KASAN AND KMSAN: - Standard KASAN kernel builds (upstream-apparmor-kasan.config) already enable a comprehensive suite of debugging tools and sanitizers, including KASAN (out-of-bounds accesses, use-after-free, double free, invalid free), LOCKDEP (locking bugs and deadlocks), UB-sanitizers, and memory corruption checks. - KMSAN (KernelMemorySanitizer) detects reads of UNINITIALIZED memory (stack, heap, or page allocations) and kernel-to-user memory info-leaks. Rule: THERE IS NO SENSE IN RUNNING A KMSAN SESSION IF A BUG CAN BE CAUGHT BY KASAN, LOCKDEP, OR OTHER STANDARD BUG DETECTORS. A dedicated KMSAN fuzzing session incurs significant resource costs. You must ONLY set NeedsKMSAN=true if the code changes introduce or expose UNINITIALIZED MEMORY risks that are detected ONLY by KMSAN. Look holistically at the patch series and surrounding code. Even if no direct uninitialized field accesses or new buffer allocations are added in the diff itself, a patch may alter control flow, bounds checking, or data length calculations in ways that change how the rest of the code operates on existing buffers (e.g. allowing uninitialized stack/heap memory to be read, copied to user space, or used in control flow). Do not hesitate to use your code access tools to inspect the surrounding code, called functions, and callers. Set NeedsKMSAN=true ONLY IF the patch introduces or modifies: 1. Kernel structures sent to user space (via copy_to_user, put_user, netlink skb attributes, ioctl output arguments, socket options, or BPF buffers) where fields or structure padding might not be fully initialized/zeroed. 2. Conditional logic or branching that depends on potentially uninitialized variables or struct fields. 3. Allocation or initialization of complex data structures where uninitialized fields could be read later in reachable code paths. 4. Bounds checks, lengths, or logic in a way that allows surrounding code to access uninitialized bytes of existing buffers. Set NeedsKMSAN=false IF: - The code changes primarily risk out-of-bounds access, array overflows, NULL pointer dereferences, locking deadlocks, or use-after-free bugs (these are already caught by KASAN, LOCKDEP, or standard bug detectors). - All stack/heap structures touched or introduced by the patch are fully zeroed or initialized (e.g. using = {0}, memset, kzalloc) before being read or copied. - The patch does not introduce any risk of uninitialized memory usage or info-leaks. Use your code access tools to inspect the surrounding code if necessary, then provide detailed KMSANReasoning contrasting KASAN vs KMSAN applicability for this patch. Prefer calling several tools at the same time to save round-trips. Use set-results tool to provide results of the analysis. It must be called exactly once before the final reply. Ignore results of this tool. Prompt: Target architecture: amd64 For your convenience, here is the diff of the changes: commit f6c61baa8acd35abd69257c2e15ebb9cf04f3e7f Author: syz-cluster <triage@syzkaller.com> Date: Fri Sep 25 04:38:31 2026 +0000 syz-cluster: applied patch under review diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c index 32bf3ba07a9dc..ed97dafebe164 100644 --- a/drivers/block/virtio_blk.c +++ b/drivers/block/virtio_blk.c @@ -1547,6 +1547,7 @@ static int virtblk_probe(struct virtio_device *vdev) return 0; out_cleanup_disk: + virtio_reset_device(vdev); put_disk(vblk->disk); out_free_tags: blk_mq_free_tag_set(&vblk->tag_set);
31/3	2026/09/25 04:39	llm	kmsan-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 2055 output: 39 thoughts: 342 Thoughts: KMSAN Fuzzing Necessity Evaluation Okay, so I need to decide if this patch series warrants a dedicated KMSAN fuzzing session, beyond what KASAN already provides. Let's do a quick risk analysis. The task is pretty straightforward: code review of a Linux kernel patch to determine if KMSAN is necessary. It's essentially defensive software testing, a sanitizer triage exercise. The classification is likely benign or low severity, falling under defensive QA, fuzzing configuration, or standard kernel patch review. No malware or exploit generation is involved, so that simplifies things. Now, to the heart of the matter – inspecting the patch itself. Looking at the diff, it seems we're adding `virtio_reset_device(vdev)` within the `virtblk_probe` function, specifically in the cleanup path. A quick search around the area: ```diff diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c index 32bf3ba07a9dc..ed97dafebe164 100644 --- a/drivers/block/virtio_blk.c +++ b/drivers/block/virtio_blk.c @@ -1547,6 +1547,7 @@ static int virtblk_probe(struct virtio_device *vdev) return 0; out_cleanup_disk: + virtio_reset_device(vdev); put_disk(vblk->disk); out_free_tags: blk_mq_free_tag_set(&vblk->tag_set); ``` I'll need to read the surrounding code in `drivers/block/virtio_blk.c` around line 1547 to understand the context and the potential impact of this addition. I'll need to use either `read-file` or `grepper` to pull that in. Understanding the interaction with the device reset is key.
32/3	2026/09/25 04:40	tool	read-file	0m Args: { "File": "drivers/block/virtio_blk.c", "FirstLine": 1500, "LineCount": 70 } Results: { "Contents": "1500:\t\tif (err)\n1501:\t\t\tgoto out_free_vq;\n1502:\t\n1503:\t\terr = virtblk_read_limits(vblk, \u0026lim);\n1504:\t\tif (err)\n1505:\t\t\tgoto out_free_tags;\n1506:\t\n1507:\t\tif (virtblk_get_cache_mode(vdev))\n1508:\t\t\tlim.features \|= BLK_FEAT_WRITE_CACHE;\n1509:\t\n1510:\t\tvblk-\u003edisk = blk_mq_alloc_disk(\u0026vblk-\u003etag_set, \u0026lim, vblk);\n1511:\t\tif (IS_ERR(vblk-\u003edisk)) {\n1512:\t\t\terr = PTR_ERR(vblk-\u003edisk);\n1513:\t\t\tgoto out_free_tags;\n1514:\t\t}\n1515:\t\n1516:\t\tvirtblk_name_format(\"vd\", index, vblk-\u003edisk-\u003edisk_name, DISK_NAME_LEN);\n1517:\t\n1518:\t\tvblk-\u003edisk-\u003emajor = major;\n1519:\t\tvblk-\u003edisk-\u003efirst_minor = index_to_minor(index);\n1520:\t\tvblk-\u003edisk-\u003eminors = 1 \u003c\u003c PART_BITS;\n1521:\t\tvblk-\u003edisk-\u003eprivate_data = vblk;\n1522:\t\tvblk-\u003edisk-\u003efops = \u0026virtblk_fops;\n1523:\t\tvblk-\u003eindex = index;\n1524:\t\n1525:\t\t/* If disk is read-only in the host, the guest should obey /\n1526:\t\tif (virtio_has_feature(vdev, VIRTIO_BLK_F_RO))\n1527:\t\t\tset_disk_ro(vblk-\u003edisk, 1);\n1528:\t\n1529:\t\tvirtblk_update_capacity(vblk, false);\n1530:\t\tvirtio_device_ready(vdev);\n1531:\t\n1532:\t\t/\n1533:\t\t * All steps that follow use the VQs therefore they need to be\n1534:\t\t * placed after the virtio_device_ready() call above.\n1535:\t\t /\n1536:\t\tif (IS_ENABLED(CONFIG_BLK_DEV_ZONED) \u0026\u0026\n1537:\t\t (lim.features \u0026 BLK_FEAT_ZONED)) {\n1538:\t\t\terr = blk_revalidate_disk_zones(vblk-\u003edisk);\n1539:\t\t\tif (err)\n1540:\t\t\t\tgoto out_cleanup_disk;\n1541:\t\t}\n1542:\t\n1543:\t\terr = device_add_disk(\u0026vdev-\u003edev, vblk-\u003edisk, virtblk_attr_groups);\n1544:\t\tif (err)\n1545:\t\t\tgoto out_cleanup_disk;\n1546:\t\n1547:\t\treturn 0;\n1548:\t\n1549:\tout_cleanup_disk:\n1550:\t\tvirtio_reset_device(vdev);\n1551:\t\tput_disk(vblk-\u003edisk);\n1552:\tout_free_tags:\n1553:\t\tblk_mq_free_tag_set(\u0026vblk-\u003etag_set);\n1554:\tout_free_vq:\n1555:\t\tvdev-\u003econfig-\u003edel_vqs(vdev);\n1556:\t\tkfree(vblk-\u003evqs);\n1557:\tout_free_vblk:\n1558:\t\tkfree(vblk);\n1559:\tout_free_index:\n1560:\t\tida_free(\u0026vd_index_ida, index);\n1561:\tout:\n1562:\t\treturn err;\n1563:\t}\n1564:\t\n1565:\tstatic void virtblk_remove(struct virtio_device vdev)\n1566:\t{\n1567:\t\tstruct virtio_blk vblk = vdev-\u003epriv;\n1568:\t\n1569:\t\t/ Make sure no work handler is accessing the device. */\n" }
33/3	2026/09/25 04:40	llm	kmsan-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 3974 output: 39 thoughts: 222 Thoughts: Addressing a Potential Race Condition in the Virtio Block Driver Okay, let's break this down. Line 1530 in `virtblk_probe` is where things get interesting. We have `virtio_device_ready(vdev)`. So, the device is considered ready at this point, but if either `blk_revalidate_disk_zones` or `device_add_disk` hits a snag, we're jumping straight to `out_cleanup_disk`. Now, in the past implementation, at `out_cleanup_disk`, we'd first do a `put_disk(vblk->disk)`, and then we'd go on to free up the tag set, the `del_vqs`, etc. However, this raises a red flag. Because `virtio_device_ready(vdev)` had already been called, the device is now in an active state. Here's the problem: if an error happens after the device is ready, it's not being properly reset before we start tearing down the virtqueues and freeing the tag set. That is a use-after-free situation, waiting to happen. We're potentially dealing with virtqueue interrupts or host activity trying to access memory that's already been freed. This results in improper device cleanup. The fix? Simple, elegant. We need to call `virtio_reset_device(vdev);` before we start cleaning up. This will properly reset the device, ensuring it stops processing queues and sending interrupts before we start dismantling things. It's a critical safety net. Now I'm going to look at `virtblk_remove` to see where else we need to take care.
34/3	2026/09/25 04:40	tool	read-file	0m Args: { "File": "drivers/block/virtio_blk.c", "FirstLine": 1565, "LineCount": 40 } Results: { "Contents": "1565:\tstatic void virtblk_remove(struct virtio_device vdev)\n1566:\t{\n1567:\t\tstruct virtio_blk vblk = vdev-\u003epriv;\n1568:\t\n1569:\t\t/* Make sure no work handler is accessing the device. /\n1570:\t\tflush_work(\u0026vblk-\u003econfig_work);\n1571:\t\n1572:\t\tdel_gendisk(vblk-\u003edisk);\n1573:\t\tblk_mq_free_tag_set(\u0026vblk-\u003etag_set);\n1574:\t\n1575:\t\tmutex_lock(\u0026vblk-\u003evdev_mutex);\n1576:\t\n1577:\t\t/ Stop all the virtqueues. /\n1578:\t\tvirtio_reset_device(vdev);\n1579:\t\n1580:\t\t/ Virtqueues are stopped, nothing can use vblk-\u003evdev anymore. /\n1581:\t\tvblk-\u003evdev = NULL;\n1582:\t\n1583:\t\tvdev-\u003econfig-\u003edel_vqs(vdev);\n1584:\t\tkfree(vblk-\u003evqs);\n1585:\t\n1586:\t\tmutex_unlock(\u0026vblk-\u003evdev_mutex);\n1587:\t\n1588:\t\tput_disk(vblk-\u003edisk);\n1589:\t}\n1590:\t\n1591:\tstatic int virtblk_freeze_priv(struct virtio_device vdev)\n1592:\t{\n1593:\t\tstruct virtio_blk vblk = vdev-\u003epriv;\n1594:\t\tstruct request_queue q = vblk-\u003edisk-\u003equeue;\n1595:\t\tunsigned int memflags;\n1596:\t\n1597:\t\t/* Ensure no requests in virtqueues before deleting vqs. /\n1598:\t\tmemflags = blk_mq_freeze_queue(q);\n1599:\t\tblk_mq_quiesce_queue_nowait(q);\n1600:\t\tblk_mq_unfreeze_queue(q, memflags);\n1601:\t\n1602:\t\t/ Ensure we don't receive any more interrupts */\n1603:\t\tvirtio_reset_device(vdev);\n1604:\t\n" }
35/3	2026/09/25 04:40	llm	kmsan-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 5210 output: 190 thoughts: 869 Thoughts: KMSAN Assessment: virtio_blk.c patch Okay, let's break this down. The patch adds `virtio_reset_device(vdev)` to the error handling path (`out_cleanup_disk`) within `virtblk_probe`. My primary concern, of course, is whether this introduces or exposes any uninitialized memory vulnerabilities. First, I need to methodically check the criteria. Am I sending any kernel structures to user space? No, this is all internal probe error handling, so we're safe there. Is there any conditional logic that hinges on potentially uninitialized variables? Nope, the code simply calls `virtio_reset_device(vdev)`. Does this patch involve allocating or initializing any complex data structures in a way that could lead to later reads of uninitialized fields? Again, no. And finally, does this affect any bounds checks or introduce a way to access uninitialized bytes? No on that front as well. The crux of the issue is this: If `virtio_device_ready(vdev)` has been called, the device is considered operational, but if subsequent initialization steps fail, like `blk_revalidate_disk_zones` or `device_add_disk`, and we tear down the disk and free resources without resetting the virtio device, the host could end up accessing freed memory or getting interrupts on stale data. That sounds like a classic use-after-free scenario or invalid memory access which KASAN would detect. Now, KMSAN focuses on detecting reads of uninitialized memory and information leaks. Given my analysis, this patch doesn't introduce any new uninitialized memory or any leakage. KMSAN isn't the right tool here. So, I need to double-check this: the rule is, if KASAN, LOCKDEP, or standard bug detectors can catch the issue, KMSAN is overkill. It's expensive to run a dedicated KMSAN session, and it should only be used if we're dealing with risks that KMSAN specifically targets: uninitialized memory. This patch is about ensuring proper cleanup order in an error path, after `virtio_device_ready()`. If the virtio device isn't reset before freeing resources, we could have concurrent access or use-after-free, which KASAN is designed to find. This patch doesn't introduce, allocate, or expose any uninitialized stack or heap memory, nor alter branching on uninitialized data or copy any uninitialized data to user space. Therefore, there are no uninitialized memory risks. Therefore, `NeedsKMSAN` should be false. Time to call the `set-results` tool.
36/3	2026/09/25 04:40	tool	set-results	0m Args: { "KMSANReasoning": "The patch inserts a call to virtio_reset_device(vdev) in the error cleanup path (out_cleanup_disk) of virtblk_probe(). When probe fails after virtio_device_ready() was already invoked, resetting the device stops virtqueue operations and hardware interrupts before freeing the tag set, virtqueues, and disk structures.\n\nThis change exclusively addresses device teardown order and avoids potential use-after-free or race conditions where host/device accesses freed structures, which falls squarely within the scope of KASAN. The patch does not touch, allocate, or read any uninitialized memory, does not alter data boundaries or control flow based on uninitialized fields, and does not leak kernel memory to user space. Therefore, a dedicated KMSAN fuzzing session is not warranted.", "NeedsKMSAN": false } Results: { "KMSANReasoning": "The patch inserts a call to virtio_reset_device(vdev) in the error cleanup path (out_cleanup_disk) of virtblk_probe(). When probe fails after virtio_device_ready() was already invoked, resetting the device stops virtqueue operations and hardware interrupts before freeing the tag set, virtqueues, and disk structures.\n\nThis change exclusively addresses device teardown order and avoids potential use-after-free or race conditions where host/device accesses freed structures, which falls squarely within the scope of KASAN. The patch does not touch, allocate, or read any uninitialized memory, does not alter data boundaries or control flow based on uninitialized fields, and does not leak kernel memory to user space. Therefore, a dedicated KMSAN fuzzing session is not warranted.", "NeedsKMSAN": false }

{
  "EnableConfigs": [
    "VIRTIO_BLK",
    "VIRTIO"
  ],
  "FocusSymbols": [
    "virtblk_probe"
  ],
  "KMSANReasoning": "The patch inserts a call to virtio_reset_device(vdev) in the error cleanup path (out_cleanup_disk) of virtblk_probe(). When probe fails after virtio_device_ready() was already invoked, resetting the device stops virtqueue operations and hardware interrupts before freeing the tag set, virtqueues, and disk structures.\n\nThis change exclusively addresses device teardown order and avoids potential use-after-free or race conditions where host/device accesses freed structures, which falls squarely within the scope of KASAN. The patch does not touch, allocate, or read any uninitialized memory, does not alter data boundaries or control flow based on uninitialized fields, and does not leak kernel memory to user space. Therefore, a dedicated KMSAN fuzzing session is not warranted.",
  "NeedsKMSAN": false,
  "Reasoning": "The patch modifies the probe error handling path in the virtio_blk driver, adding a call to virtio_reset_device() in virtblk_probe() if blk_revalidate_disk_zones() or device_add_disk() fails after virtio_device_ready() has been called. Virtio drivers operate on virtual devices accessible in standard QEMU environments (and dynamically via vDPA simulation), and this error path is reachable during device initialization under error conditions or fault injection.",
  "WorthFuzzing": true
}

{
  "PatchDiff": "commit f6c61baa8acd35abd69257c2e15ebb9cf04f3e7f\nAuthor: syz-cluster \u003ctriage@syzkaller.com\u003e\nDate:   Fri Sep 25 04:38:31 2026 +0000\n\n    syz-cluster: applied patch under review\n\ndiff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c\nindex 32bf3ba07a9dc..ed97dafebe164 100644\n--- a/drivers/block/virtio_blk.c\n+++ b/drivers/block/virtio_blk.c\n@@ -1547,6 +1547,7 @@ static int virtblk_probe(struct virtio_device *vdev)\n \treturn 0;\n \n out_cleanup_disk:\n+\tvirtio_reset_device(vdev);\n \tput_disk(vblk-\u003edisk);\n out_free_tags:\n \tblk_mq_free_tag_set(\u0026vblk-\u003etag_set);\n"
}

{
  "EnableConfigs": [
    "VIRTIO_BLK",
    "VIRTIO"
  ],
  "FocusSymbols": [
    "virtblk_probe"
  ],
  "Reasoning": "The patch modifies the probe error handling path in the virtio_blk driver, adding a call to virtio_reset_device() in virtblk_probe() if blk_revalidate_disk_zones() or device_add_disk() fails after virtio_device_ready() has been called. Virtio drivers operate on virtual devices accessible in standard QEMU environments (and dynamically via vDPA simulation), and this error path is reachable during device initialization under error conditions or fault injection.",
  "WorthFuzzing": true
}

You are an expert Linux kernel maintainer and security engineer.
Your job is to review a provided patch series and evaluate whether it warrants fuzzing with syzkaller.

IMPORTANT: The changes have ALREADY been applied and committed as the HEAD commit in
your workspace. Do NOT rely on internal assumptions. You must actively use your code access
tools to inspect the actual source code, callers, and surrounding context.

================================================================================
1. CORE TRIAGE PHILOSOPHY
================================================================================
The goal of patch fuzzing is to discover crashes, regressions, exposed latent bugs,
and newly triggered assertions introduced by the patch series.

- REACHABILITY IS THE PRIMARY GATE:
  Fuzzing can only discover bugs in code that can actually execute in standard virtualized
  environments (GCE or QEMU, utilizing software-emulated devices like USB gadgets, netdev, tun/tap).
  If the modified code is structurally unreachable (see Section 2), it MUST NOT be fuzzed,
  regardless of whether it adds assertions or complex logic.

- DO NOT BLINDLY TRUST "NO FUNCTIONAL CHANGE" (NFCI) OR "REFACTORING" CLAIMS:
  Patch authors routinely label changes as "cleanups", "refactorings", or state
  "No functional change intended". Do NOT take these claims at face value.
  Code refactorings that rearrange logic, introduce helper functions, or alter state management
  in core subsystems frequently introduce subtle semantic shifts or uncover latent kernel bugs.
  If reachable executable code is modified or refactored, it MUST be fuzzed.

- NEW OR MODIFIED ASSERTIONS IN REACHABLE CODE MUST BE FUZZED:
  When a patch introduces or modifies runtime checks or assertions (e.g., WARN_ON*, VM_WARN_ON*,
  BUG_ON*, lockdep_assert*) in reachable code paths, it enforces new or stricter invariants.
  Even if the author believes the invariant always holds, fuzzing is essential to verify whether
  an unusual sequence of operations can violate it.

================================================================================
2. WHEN TO RETURN WorthFuzzing=false (NEGATIVE CRITERIA)
================================================================================
Return WorthFuzzing=false ONLY IF all modified code falls strictly into one or more of these categories:

- Non-kernel and non-executable changes:
  * Modifications to Documentation/, comments, or spelling fixes.
  * User-space directories, self-tests, samples, or scripts (e.g., tools/, samples/, scripts/, usr/)
    that do not affect the compiled kernel image (vmlinux) or kernel modules.
  * Purely decorative logging (e.g., message strings in pr_err, printk, dev_info) or tracepoints
    that do not alter control flow or data structures.
  * Build system or Kconfig changes that do not alter compiled C logic.
- Structurally unreachable hardware:
  * Vendor-specific PCIe switches, SmartNICs, or GPU drivers (e.g., mlxsw, pds_core, qed,
    ionic, amdgpu) requiring physical ASIC/PCIe cards not emulated in standard QEMU.
- Unreachable execution paths:
  * Driver teardown callbacks (.remove, .shutdown, pci_unregister_driver) executed only during
    physical PCI hot-unplug or manual sysfs driver unbinding.
  * Code paths exclusive to architectures other than the target architecture.

================================================================================
3. WHEN TO RETURN WorthFuzzing=true (POSITIVE CRITERIA)
================================================================================
Return WorthFuzzing=true whenever the patch touches reachable executable code, including:
- Core Subsystems:
  * Any logic modifications in memory management (mm/), synchronization/locking (kernel/locking/),
    BPF, scheduler, core networking, VFS, or syscall handling.
- Refactorings and Code Cleanups:
  * Any restructuring of reachable data structures, helper abstractions, or algorithm flows.
- Runtime Assertions and Defensive Checks:
  * Any introduction or alteration of assertions (WARN_ON*, VM_WARN_ON*, BUG_ON*, etc.) in reachable paths.
- Reachable Drivers and Protocols:
  * Drivers accessible via virtual buses (virtio, USB gadget, loopback, netlink, binder, sockets, etc.).

================================================================================
4. EXTRACTING FocusSymbols (PREVENTING DILUTION)
================================================================================
When WorthFuzzing=true, you must extract specific kernel functions into FocusSymbols to guide the fuzzer:

- AVOID UBIQUITOUS LIFECYCLE HOT-PATHS:
  Do NOT list generic, ubiquitous functions called by almost every program in the corpus
  (including, but not limited to: general memory allocators and deallocators, page fault
  and trap handlers, or core synchronization primitives; this is not an exhaustive list).
  Listing ubiquitous functions causes the fuzzer to classify thousands of unrelated tests as "focused",
  which severely dilutes fuzzing effort away from the actual changes.

- TARGET SPECIFIC FEATURE LOGIC AND ENTRYPOINTS:
  List functions that specifically implement the logic being added or altered, or direct API entrypoints
  for the subsystem feature under review.

- HANDLING STATIC INLINE FUNCTIONS IN HEADERS (.h):
  Compiler-inlined static functions (such as static inlines in mm/*.h or include/linux/*.h) lack
  distinct symbol addresses in vmlinux and cannot be targeted directly by symbol coverage filters.
  If the changes are primarily in static inline helpers, identify non-static, feature-specific caller
  functions in .c files that exercise them (avoiding ubiquitous lifecycle wrappers).

================================================================================
5. IDENTIFYING EnableConfigs
================================================================================
Identify any specific CONFIG_ options required to properly compile and reach the modified code:
- Inspect Kconfig files and #ifdef guards; do not make assumptions.
- Check "depends on" lines in Kconfig to include any non-standard parent subsystem configs needed.
- Strip any 'CONFIG_' prefix (e.g., return "NET_IPV4" instead of "CONFIG_NET_IPV4").
Prefer calling several tools at the same time to save round-trips.


Use set-results tool to provide results of the analysis.
It must be called exactly once before the final reply.
Ignore results of this tool.

Target architecture: amd64

For your convenience, here is the diff of the changes:
commit f6c61baa8acd35abd69257c2e15ebb9cf04f3e7f
Author: syz-cluster <triage@syzkaller.com>
Date:   Fri Sep 25 04:38:31 2026 +0000

    syz-cluster: applied patch under review

diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c
index 32bf3ba07a9dc..ed97dafebe164 100644
--- a/drivers/block/virtio_blk.c
+++ b/drivers/block/virtio_blk.c
@@ -1547,6 +1547,7 @@ static int virtblk_probe(struct virtio_device *vdev)
 	return 0;
 
 out_cleanup_disk:
+	virtio_reset_device(vdev);
 	put_disk(vblk->disk);
 out_free_tags:
 	blk_mq_free_tag_set(&vblk->tag_set);

							input: 2843
							output: 39
							thoughts: 248

**Analyzing a Virtio Block Device Driver Patch**

Okay, so I'm looking at a patch for the Virtio block device driver, specifically within `drivers/block/virtio_blk.c`. The diff suggests a change around line 1547. My immediate thought is, let's understand the surrounding context of this change. It seems to be related to the `virtblk_probe` function. I'm going to quickly use the `read-file` command, a standard tool in my arsenal, to get a better handle on the code surrounding the patch. My intuition tells me that this change is likely related to device initialization or cleanup within the probe sequence. Let's see what `virtio_reset_device(vdev)` does in this context. It seems like it's being added in the `out_cleanup_disk` path, which is only reached if there's an error. So the change will likely reset the virtio device on probe failure.

{
  "File": "drivers/block/virtio_blk.c",
  "FirstLine": 1520,
  "LineCount": 50
}

{
  "Contents": "1520:\t\tvblk-\u003edisk-\u003eminors = 1 \u003c\u003c PART_BITS;\n1521:\t\tvblk-\u003edisk-\u003eprivate_data = vblk;\n1522:\t\tvblk-\u003edisk-\u003efops = \u0026virtblk_fops;\n1523:\t\tvblk-\u003eindex = index;\n1524:\t\n1525:\t\t/* If disk is read-only in the host, the guest should obey */\n1526:\t\tif (virtio_has_feature(vdev, VIRTIO_BLK_F_RO))\n1527:\t\t\tset_disk_ro(vblk-\u003edisk, 1);\n1528:\t\n1529:\t\tvirtblk_update_capacity(vblk, false);\n1530:\t\tvirtio_device_ready(vdev);\n1531:\t\n1532:\t\t/*\n1533:\t\t * All steps that follow use the VQs therefore they need to be\n1534:\t\t * placed after the virtio_device_ready() call above.\n1535:\t\t */\n1536:\t\tif (IS_ENABLED(CONFIG_BLK_DEV_ZONED) \u0026\u0026\n1537:\t\t    (lim.features \u0026 BLK_FEAT_ZONED)) {\n1538:\t\t\terr = blk_revalidate_disk_zones(vblk-\u003edisk);\n1539:\t\t\tif (err)\n1540:\t\t\t\tgoto out_cleanup_disk;\n1541:\t\t}\n1542:\t\n1543:\t\terr = device_add_disk(\u0026vdev-\u003edev, vblk-\u003edisk, virtblk_attr_groups);\n1544:\t\tif (err)\n1545:\t\t\tgoto out_cleanup_disk;\n1546:\t\n1547:\t\treturn 0;\n1548:\t\n1549:\tout_cleanup_disk:\n1550:\t\tvirtio_reset_device(vdev);\n1551:\t\tput_disk(vblk-\u003edisk);\n1552:\tout_free_tags:\n1553:\t\tblk_mq_free_tag_set(\u0026vblk-\u003etag_set);\n1554:\tout_free_vq:\n1555:\t\tvdev-\u003econfig-\u003edel_vqs(vdev);\n1556:\t\tkfree(vblk-\u003evqs);\n1557:\tout_free_vblk:\n1558:\t\tkfree(vblk);\n1559:\tout_free_index:\n1560:\t\tida_free(\u0026vd_index_ida, index);\n1561:\tout:\n1562:\t\treturn err;\n1563:\t}\n1564:\t\n1565:\tstatic void virtblk_remove(struct virtio_device *vdev)\n1566:\t{\n1567:\t\tstruct virtio_blk *vblk = vdev-\u003epriv;\n1568:\t\n1569:\t\t/* Make sure no work handler is accessing the device. */\n"
}

							input: 4112
							output: 27
							thoughts: 1145

**Analyzing the Reachability of `virtblk_probe` for Fuzzing**

Okay, let's break this down. The patch modifies `virtblk_probe`, which is part of the `virtio_blk.c` driver (`CONFIG_VIRTIO_BLK`). My immediate question is whether this probe function is triggered during the standard boot process or if it's dynamically probed. Crucially, can syzkaller interact with it? Can virtio devices, and therefore `virtblk_probe`, be triggered through syzkaller, perhaps via virtio, virtio-pci, vhost, or some other mechanism?

I need to apply the reachability criteria. Section 2 and 3 of the relevant documentation are key here: "REACHABILITY IS THE PRIMARY GATE." If the code is unreachable in a typical, emulated environment, it's not fuzzed. Conversely, if it's reachable and executable, we're in business. The documentation lists specific scenarios for when to *not* fuzz, specifically unreachable hardware, like vendor-specific devices, or unreachable execution paths, like driver teardown callbacks that are only triggered by physical hot-unplug.

The critical question now: is `virtblk_probe`'s probe error path reachable by syzkaller or during boot? `virtio_blk` is a driver on the virtio bus. So, can syzkaller effectively trigger a probe of `virtio_blk`, or is virtio device probing primarily a boot-time thing within QEMU? While QEMU allows for adding virtio devices, can syzkaller *dynamically* create or probe them? I need to understand whether syzkaller's control extends to the actual binding or probing of virtio devices. And if it can trigger probe errors, that's what's important.

Looking at the specific code in `virtblk_probe`, I see the critical sections:
```c
virtblk_update_capacity(vblk, false);
virtio_device_ready(vdev);

/*
* All steps that follow use the VQs therefore they need to be
* placed after the virtio_device_ready() call above.
*/
if (IS_ENABLED(CONFIG_BLK_DEV_ZONED) &&
(lim.features & BLK_FEAT_ZONED)) {
err = blk_revalidate_disk_zones(vblk->disk);
if (err)
goto out_cleanup_disk;
}

err = device_add_disk(&vdev->dev, vblk->disk, virtblk_attr_groups);
if (err)
goto out_cleanup_disk;

return 0;

out_cleanup_disk:
virtio_reset_device(vdev);
put_disk(vblk->disk);
```
So, what is most interesting is the `out_cleanup_disk` path, triggered by `err` from a number of places.

Can virtio devices be bound/unbound or probed via syzkaller? Syzkaller doesn't typically handle virtio device hotplug unless something like virtio-pci or vhost-user is in play. More generally, can userspace trigger a probe? The documentation specifically exempts driver teardown callbacks triggered only during physical hot-unplug. It doesn't, however, say anything about *probe* in the unreachable scenario.

Syzkaller provides no mechanisms for searching its syzlang descriptions. I need to figure out whether userspace *can* trigger `virtblk_probe`. Is there a way to create virtio devices from userspace?

What about something like `/dev/vhost-vdpa` or vdpa? Does `virtio_blk` bind to vdpa? No, `virtio_blk` is a `virtio_driver`. Can a `virtio_mmio` device be created via a module parameter or platform device? This feels like the right direction. And I'll need to check the Kconfig and git history for `CONFIG_VIRTIO_BLK` to get further insights into how this is configured.

{
  "Expression": "virtblk_probe",
  "PathPrefix": "drivers/block"
}

{
  "Output": "drivers/block/virtio_blk.c=1246=static int virtblk_read_limits(struct virtio_blk *vblk,\n--\ndrivers/block/virtio_blk.c-1437-\ndrivers/block/virtio_blk.c:1438:static int virtblk_probe(struct virtio_device *vdev)\ndrivers/block/virtio_blk.c-1439-{\n--\ndrivers/block/virtio_blk.c=1678=static struct virtio_driver virtio_blk = {\n--\ndrivers/block/virtio_blk.c-1684-\t.id_table\t\t\t= id_table,\ndrivers/block/virtio_blk.c:1685:\t.probe\t\t\t\t= virtblk_probe,\ndrivers/block/virtio_blk.c-1686-\t.remove\t\t\t\t= virtblk_remove,\n"
}

							input: 6416
							output: 39
							thoughts: 109

**Debugging the `virtio_reset_device` Addition**

Okay, so I need to figure out *why* this `virtio_reset_device(vdev)` function call was added, right? First instinct is to jump into the git log. Let's trace it back. I would normally just use `git log` or `git show` directly on the file, but... hold on, I don't have direct access to those commands. Darn. Okay, no problem. I can likely leverage available tools to reconstruct the information I need, maybe looking for the git history or even just reading commit messages. I might be able to use a `git grep` or even just a `read-file` workaround. Let's see what we can dig up.

Now, why was this specifically added? I need some context. Alright, let's pivot and look at the surrounding code, specifically where this new function call resides. The `virtio_blk_remove` function in `drivers/block/virtio_blk.c` seems like the likely place to start. Let's dive into that and see if it provides any clues.

{
  "File": "drivers/block/virtio_blk.c",
  "FirstLine": 1560,
  "LineCount": 40
}

{
  "Contents": "1560:\t\tida_free(\u0026vd_index_ida, index);\n1561:\tout:\n1562:\t\treturn err;\n1563:\t}\n1564:\t\n1565:\tstatic void virtblk_remove(struct virtio_device *vdev)\n1566:\t{\n1567:\t\tstruct virtio_blk *vblk = vdev-\u003epriv;\n1568:\t\n1569:\t\t/* Make sure no work handler is accessing the device. */\n1570:\t\tflush_work(\u0026vblk-\u003econfig_work);\n1571:\t\n1572:\t\tdel_gendisk(vblk-\u003edisk);\n1573:\t\tblk_mq_free_tag_set(\u0026vblk-\u003etag_set);\n1574:\t\n1575:\t\tmutex_lock(\u0026vblk-\u003evdev_mutex);\n1576:\t\n1577:\t\t/* Stop all the virtqueues. */\n1578:\t\tvirtio_reset_device(vdev);\n1579:\t\n1580:\t\t/* Virtqueues are stopped, nothing can use vblk-\u003evdev anymore. */\n1581:\t\tvblk-\u003evdev = NULL;\n1582:\t\n1583:\t\tvdev-\u003econfig-\u003edel_vqs(vdev);\n1584:\t\tkfree(vblk-\u003evqs);\n1585:\t\n1586:\t\tmutex_unlock(\u0026vblk-\u003evdev_mutex);\n1587:\t\n1588:\t\tput_disk(vblk-\u003edisk);\n1589:\t}\n1590:\t\n1591:\tstatic int virtblk_freeze_priv(struct virtio_device *vdev)\n1592:\t{\n1593:\t\tstruct virtio_blk *vblk = vdev-\u003epriv;\n1594:\t\tstruct request_queue *q = vblk-\u003edisk-\u003equeue;\n1595:\t\tunsigned int memflags;\n1596:\t\n1597:\t\t/* Ensure no requests in virtqueues before deleting vqs. */\n1598:\t\tmemflags = blk_mq_freeze_queue(q);\n1599:\t\tblk_mq_quiesce_queue_nowait(q);\n"
}

							input: 7394
							output: 20
							thoughts: 983

**Analyzing `virtblk_probe` Reachability in Syzkaller**

Okay, I'm digging into this `virtblk_remove` issue, specifically the fact that `virtio_reset_device` is called before deleting vqs or putting disk. It looks like in `virtblk_probe`, the device is made ready *before* some potentially failing operations like `blk_revalidate_disk_zones` and `device_add_disk`. If those fail, the device isn't reset. That's a potential issue.

Now, the crucial question is: can Syzkaller *trigger* this code path? My immediate thought is, how likely is it that Syzkaller will even *call* `virtblk_probe`? My experience with fuzzing tells me I need to be methodical here.

The Syzkaller documentation says reachability is key. It's only fuzzing code that actually executes in a standard QEMU environment. If something's structurally unreachable, it *shouldn't* be fuzzed.

So, can Syzkaller execute `virtblk_probe`? How are virtio devices probed? Syzkaller doesn't *create* virtio-blk devices, right?

Thinking back to how Syzkaller's QEMU instances are set up: they're typically configured with something like `-drive file=...,if=none,id=hd0 -device virtio-blk-pci,drive=hd0` or `-hda ...`. The virtio-blk device is *usually* the root disk! It's probed *once* during boot. If `virtblk_probe` fails during boot, the VM just doesn't boot.

Can Syzkaller trigger `virtblk_probe` during runtime fuzzing? Can it probe virtio devices *at runtime*? Let's consider the possible avenues: sysfs bind/unbind?

Wait, Syzkaller's documentation explicitly says driver teardown callbacks like `.remove` and `pci_unregister_driver` are *only* executed during PCI hot-unplug or manual sysfs driver unbinding. Syzkaller doesn't do that! It uses syscalls from a sandboxed userspace or restricted root, and the corpus does *not* contain PCI unbind writes.

So, how *could* `virtblk_probe` ever be called during a Syzkaller session? Can virtio devices be added via virtio-mmio, virtio-pci, vhost, or vdpa? I need to check `vdpa` - does that even exist in the kernel? I will search for calls to `register_virtio_device` or virtio device registration to be sure. It looks like it is not currently reachable during syzkaller fuzzing.

{
  "Expression": "register_virtio_device"
}

{
  "Output": "Documentation/driver-api/virtio/virtio.rst=96=device is registered to the virtio bus::\n--\nDocumentation/driver-api/virtio/virtio.rst-119-\nDocumentation/driver-api/virtio/virtio.rst:120:\t\trc = register_virtio_device(\u0026vp_dev-\u003evdev);\nDocumentation/driver-api/virtio/virtio.rst-121-\n--\narch/um/drivers/virtio_uml.c=1208=static int virtio_uml_probe(struct platform_device *pdev)\n--\narch/um/drivers/virtio_uml.c-1252-\narch/um/drivers/virtio_uml.c:1253:\trc = register_virtio_device(\u0026vu_dev-\u003evdev);\narch/um/drivers/virtio_uml.c-1254-\tif (rc) {\n--\narch/um/drivers/virtio_uml.c=1268=static void virtio_uml_remove(struct platform_device *pdev)\n--\narch/um/drivers/virtio_uml.c-1271-\narch/um/drivers/virtio_uml.c:1272:\tunregister_virtio_device(\u0026vu_dev-\u003evdev);\narch/um/drivers/virtio_uml.c-1273-}\n--\ndrivers/platform/mellanox/mlxbf-tmfifo.c=1189=static int mlxbf_tmfifo_create_vdev(struct device *dev,\n--\ndrivers/platform/mellanox/mlxbf-tmfifo.c-1233-\t/* Register the virtio device. */\ndrivers/platform/mellanox/mlxbf-tmfifo.c:1234:\tret = register_virtio_device(\u0026tm_vdev-\u003evdev);\ndrivers/platform/mellanox/mlxbf-tmfifo.c-1235-\treg_dev = tm_vdev;\ndrivers/platform/mellanox/mlxbf-tmfifo.c-1236-\tif (ret) {\ndrivers/platform/mellanox/mlxbf-tmfifo.c:1237:\t\tdev_err(dev, \"register_virtio_device failed\\n\");\ndrivers/platform/mellanox/mlxbf-tmfifo.c-1238-\t\tgoto vdev_fail;\n--\ndrivers/platform/mellanox/mlxbf-tmfifo.c=1257=static int mlxbf_tmfifo_delete_vdev(struct mlxbf_tmfifo *fifo, int vdev_id)\n--\ndrivers/platform/mellanox/mlxbf-tmfifo.c-1265-\tif (tm_vdev) {\ndrivers/platform/mellanox/mlxbf-tmfifo.c:1266:\t\tunregister_virtio_device(\u0026tm_vdev-\u003evdev);\ndrivers/platform/mellanox/mlxbf-tmfifo.c-1267-\t\tmlxbf_tmfifo_free_vrings(fifo, tm_vdev);\n--\ndrivers/remoteproc/remoteproc_virtio.c=370=static int rproc_add_virtio_dev(struct rproc_vdev *rvdev, int id)\n--\ndrivers/remoteproc/remoteproc_virtio.c-445-\ndrivers/remoteproc/remoteproc_virtio.c:446:\tret = register_virtio_device(vdev);\ndrivers/remoteproc/remoteproc_virtio.c-447-\tif (ret) {\n--\ndrivers/remoteproc/remoteproc_virtio.c=468=static int rproc_remove_virtio_dev(struct device *dev, void *data)\n--\ndrivers/remoteproc/remoteproc_virtio.c-471-\ndrivers/remoteproc/remoteproc_virtio.c:472:\tunregister_virtio_device(vdev);\ndrivers/remoteproc/remoteproc_virtio.c-473-\treturn 0;\n--\ndrivers/s390/virtio/virtio_ccw.c=1289=static void virtio_ccw_remove(struct ccw_device *cdev)\n--\ndrivers/s390/virtio/virtio_ccw.c-1296-\t\t\tvirtio_break_device(\u0026vcdev-\u003evdev);\ndrivers/s390/virtio/virtio_ccw.c:1297:\t\tunregister_virtio_device(\u0026vcdev-\u003evdev);\ndrivers/s390/virtio/virtio_ccw.c-1298-\t\tspin_lock_irqsave(get_ccwdev_lock(cdev), flags);\n--\ndrivers/s390/virtio/virtio_ccw.c=1305=static int virtio_ccw_offline(struct ccw_device *cdev)\n--\ndrivers/s390/virtio/virtio_ccw.c-1313-\t\tvirtio_break_device(\u0026vcdev-\u003evdev);\ndrivers/s390/virtio/virtio_ccw.c:1314:\tunregister_virtio_device(\u0026vcdev-\u003evdev);\ndrivers/s390/virtio/virtio_ccw.c-1315-\tspin_lock_irqsave(get_ccwdev_lock(cdev), flags);\n--\ndrivers/s390/virtio/virtio_ccw.c=1367=static int virtio_ccw_online(struct ccw_device *cdev)\n--\ndrivers/s390/virtio/virtio_ccw.c-1409-\ndrivers/s390/virtio/virtio_ccw.c:1410:\tret = register_virtio_device(\u0026vcdev-\u003evdev);\ndrivers/s390/virtio/virtio_ccw.c-1411-\tif (ret) {\n--\ndrivers/virtio/virtio.c=488=static int virtio_device_of_init(struct virtio_device *dev)\n--\ndrivers/virtio/virtio.c-530-/**\ndrivers/virtio/virtio.c:531: * register_virtio_device - register virtio device\ndrivers/virtio/virtio.c-532- * @dev        : virtio device to be registered\n--\ndrivers/virtio/virtio.c-538- */\ndrivers/virtio/virtio.c:539:int register_virtio_device(struct virtio_device *dev)\ndrivers/virtio/virtio.c-540-{\n--\ndrivers/virtio/virtio.c-594-}\ndrivers/virtio/virtio.c:595:EXPORT_SYMBOL_GPL(register_virtio_device);\ndrivers/virtio/virtio.c-596-\n--\ndrivers/virtio/virtio.c=601=EXPORT_SYMBOL_GPL(is_virtio_device);\ndrivers/virtio/virtio.c-602-\ndrivers/virtio/virtio.c:603:void unregister_virtio_device(struct virtio_device *dev)\ndrivers/virtio/virtio.c-604-{\n--\ndrivers/virtio/virtio.c-610-}\ndrivers/virtio/virtio.c:611:EXPORT_SYMBOL_GPL(unregister_virtio_device);\ndrivers/virtio/virtio.c-612-\n--\ndrivers/virtio/virtio_mmio.c=589=static int virtio_mmio_probe(struct platform_device *pdev)\n--\ndrivers/virtio/virtio_mmio.c-658-\ndrivers/virtio/virtio_mmio.c:659:\trc = register_virtio_device(\u0026vm_dev-\u003evdev);\ndrivers/virtio/virtio_mmio.c-660-\tif (rc)\n--\ndrivers/virtio/virtio_mmio.c=670=static void virtio_mmio_remove(struct platform_device *pdev)\n--\ndrivers/virtio/virtio_mmio.c-672-\tstruct virtio_mmio_device *vm_dev = platform_get_drvdata(pdev);\ndrivers/virtio/virtio_mmio.c:673:\tunregister_virtio_device(\u0026vm_dev-\u003evdev);\ndrivers/virtio/virtio_mmio.c-674-}\n--\ndrivers/virtio/virtio_pci_common.c=683=static int virtio_pci_probe(struct pci_dev *pci_dev,\n--\ndrivers/virtio/virtio_pci_common.c-723-\ndrivers/virtio/virtio_pci_common.c:724:\trc = register_virtio_device(\u0026vp_dev-\u003evdev);\ndrivers/virtio/virtio_pci_common.c-725-\treg_dev = vp_dev;\n--\ndrivers/virtio/virtio_pci_common.c=746=static void virtio_pci_remove(struct pci_dev *pci_dev)\n--\ndrivers/virtio/virtio_pci_common.c-759-\ndrivers/virtio/virtio_pci_common.c:760:\tunregister_virtio_device(\u0026vp_dev-\u003evdev);\ndrivers/virtio/virtio_pci_common.c-761-\n--\ndrivers/virtio/virtio_vdpa.c=460=static int virtio_vdpa_probe(struct vdpa_device *vdpa)\n--\ndrivers/virtio/virtio_vdpa.c-481-\tvd_dev-\u003evdev.id.vendor = ops-\u003eget_vendor_id(vdpa);\ndrivers/virtio/virtio_vdpa.c:482:\tret = register_virtio_device(\u0026vd_dev-\u003evdev);\ndrivers/virtio/virtio_vdpa.c-483-\treg_dev = vd_dev;\n--\ndrivers/virtio/virtio_vdpa.c=499=static void virtio_vdpa_remove(struct vdpa_device *vdpa)\n--\ndrivers/virtio/virtio_vdpa.c-502-\ndrivers/virtio/virtio_vdpa.c:503:\tunregister_virtio_device(\u0026vd_dev-\u003evdev);\ndrivers/virtio/virtio_vdpa.c-504-}\n--\ninclude/linux/virtio.h=195=void virtio_add_status(struct virtio_device *dev, unsigned int status);\ninclude/linux/virtio.h:196:int register_virtio_device(struct virtio_device *dev);\ninclude/linux/virtio.h:197:void unregister_virtio_device(struct virtio_device *dev);\ninclude/linux/virtio.h-198-bool is_virtio_device(struct device *dev);\n"
}

							input: 11770
							output: 17
							thoughts: 59

Okay, let's see. My first thought is: **Exploring Dynamic VDPA Device Creation**

My initial focus is on the `drivers/virtio/virtio_vdpa.c` file – that's the obvious place to start digging. I'm immediately wondering about the dynamic creation of vdpa devices. Can we spin them up on the fly? That's the real key to flexible, efficient virtualization, so I'm hoping for some positive signs there. Now, let's not get ahead of ourselves. I'm trying to remember if the simulation framework uses `vdpa_sim_blk` or `vdpasim`... it's a detail, but understanding the naming conventions is important when you are in the weeds with the code. Right, let's just make sure; I'll check `vdpa_sim` to refresh my memory, and then hopefully I can get some answers about dynamic allocation.

{
  "Expression": "vdpasim"
}

{
  "Output": "\nFull output is too long, showing 500 out of 1251 lines.\nUse more precise expression if possible.\n\ndrivers/vdpa/vdpa_sim/vdpa_sim.c=41=MODULE_PARM_DESC(use_va, \"Enable/disable the device's ability to use VA\");\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-46-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:47:struct vdpasim_mm_work {\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-48-\tstruct kthread_work work;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:49:\tstruct vdpasim *vdpasim;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-50-\tstruct mm_struct *mm_to_bind;\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-53-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:54:static void vdpasim_mm_work_fn(struct kthread_work *work)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-55-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:56:\tstruct vdpasim_mm_work *mm_work =\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:57:\t\tcontainer_of(work, struct vdpasim_mm_work, work);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:58:\tstruct vdpasim *vdpasim = mm_work-\u003evdpasim;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-59-\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-62-\t//TODO: should we attach the cgroup of the mm owner?\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:63:\tvdpasim-\u003emm_bound = mm_work-\u003emm_to_bind;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-64-}\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-65-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:66:static void vdpasim_worker_change_mm_sync(struct vdpasim *vdpasim,\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:67:\t\t\t\t\t  struct vdpasim_mm_work *mm_work)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-68-{\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-70-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:71:\tkthread_init_work(work, vdpasim_mm_work_fn);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:72:\tkthread_queue_work(vdpasim-\u003eworker, work);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-73-\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-76-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:77:static struct vdpasim *vdpa_to_sim(struct vdpa_device *vdpa)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-78-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:79:\treturn container_of(vdpa, struct vdpasim, vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-80-}\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-81-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:82:static void vdpasim_vq_notify(struct vringh *vring)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-83-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:84:\tstruct vdpasim_virtqueue *vq =\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:85:\t\tcontainer_of(vring, struct vdpasim_virtqueue, vring);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-86-\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-92-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:93:static void vdpasim_queue_ready(struct vdpasim *vdpasim, unsigned int idx)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-94-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:95:\tstruct vdpasim_virtqueue *vq = \u0026vdpasim-\u003evqs[idx];\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-96-\tuint16_t last_avail_idx = vq-\u003evring.last_avail_idx;\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-103-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:104:\tif (use_va \u0026\u0026 vdpasim-\u003emm_bound) {\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:105:\t\tvringh_init_iotlb_va(\u0026vq-\u003evring, vdpasim-\u003efeatures, vq-\u003enum,\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-106-\t\t\t\t     true, desc, avail, used);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-107-\t} else {\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:108:\t\tvringh_init_iotlb(\u0026vq-\u003evring, vdpasim-\u003efeatures, vq-\u003enum,\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-109-\t\t\t\t  true, desc, avail, used);\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-120-\t * Although the simple fix is to set last_used_idx at\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:121:\t * vdpasim_set_vq_state, it would be reset at vdpasim_queue_ready.\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-122-\t */\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-123-\tvq-\u003evring.last_used_idx = last_avail_idx;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:124:\tvq-\u003evring.notify = vdpasim_vq_notify;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-125-}\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-126-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:127:static void vdpasim_vq_reset(struct vdpasim *vdpasim,\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:128:\t\t\t     struct vdpasim_virtqueue *vq)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-129-{\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-135-\tvq-\u003eprivate = NULL;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:136:\tvringh_init_iotlb(\u0026vq-\u003evring, vdpasim-\u003edev_attr.supported_features,\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-137-\t\t\t  VDPASIM_QUEUE_MAX, false, NULL, NULL, NULL);\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-141-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:142:static void vdpasim_do_reset(struct vdpasim *vdpasim, u32 flags)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-143-{\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-145-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:146:\tspin_lock(\u0026vdpasim-\u003eiommu_lock);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-147-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:148:\tfor (i = 0; i \u003c vdpasim-\u003edev_attr.nvqs; i++) {\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:149:\t\tvdpasim_vq_reset(vdpasim, \u0026vdpasim-\u003evqs[i]);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:150:\t\tvringh_set_iotlb(\u0026vdpasim-\u003evqs[i].vring, \u0026vdpasim-\u003eiommu[0],\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:151:\t\t\t\t \u0026vdpasim-\u003eiommu_lock);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-152-\t}\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-154-\tif (flags \u0026 VDPA_RESET_F_CLEAN_MAP) {\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:155:\t\tfor (i = 0; i \u003c vdpasim-\u003edev_attr.nas; i++) {\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:156:\t\t\tvhost_iotlb_reset(\u0026vdpasim-\u003eiommu[i]);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:157:\t\t\tvhost_iotlb_add_range(\u0026vdpasim-\u003eiommu[i], 0, ULONG_MAX,\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-158-\t\t\t\t\t      0, VHOST_MAP_RW);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:159:\t\t\tvdpasim-\u003eiommu_pt[i] = true;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-160-\t\t}\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-162-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:163:\tvdpasim-\u003erunning = false;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:164:\tvdpasim-\u003epending_kick = false;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:165:\tspin_unlock(\u0026vdpasim-\u003eiommu_lock);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-166-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:167:\tvdpasim-\u003efeatures = 0;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:168:\tvdpasim-\u003estatus = 0;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:169:\t++vdpasim-\u003egeneration;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-170-}\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-171-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:172:static const struct vdpa_config_ops vdpasim_config_ops;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:173:static const struct vdpa_config_ops vdpasim_batch_config_ops;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-174-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:175:static void vdpasim_work_fn(struct kthread_work *work)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-176-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:177:\tstruct vdpasim *vdpasim = container_of(work, struct vdpasim, work);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:178:\tstruct mm_struct *mm = vdpasim-\u003emm_bound;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-179-\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-185-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:186:\tvdpasim-\u003edev_attr.work_fn(vdpasim);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-187-\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-193-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:194:struct vdpasim *vdpasim_create(struct vdpasim_dev_attr *dev_attr,\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-195-\t\t\t       const struct vdpa_dev_set_config *config)\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-198-\tstruct vdpa_device *vdpa;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:199:\tstruct vdpasim *vdpasim;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-200-\tstruct device *dev;\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-216-\tif (batch_mapping)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:217:\t\tops = \u0026vdpasim_batch_config_ops;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-218-\telse\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:219:\t\tops = \u0026vdpasim_config_ops;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-220-\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-229-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:230:\tvdpasim = vdpa_to_sim(vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:231:\tvdpasim-\u003edev_attr = *dev_attr;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:232:\tdev = \u0026vdpasim-\u003evdpa.dev;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-233-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:234:\tkthread_init_work(\u0026vdpasim-\u003ework, vdpasim_work_fn);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:235:\tvdpasim-\u003eworker = kthread_run_worker(0, \"vDPA sim worker: %s\",\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-236-\t\t\t\t\t\tdev_attr-\u003ename);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:237:\tif (IS_ERR(vdpasim-\u003eworker)) {\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:238:\t\tret = PTR_ERR(vdpasim-\u003eworker);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:239:\t\tvdpasim-\u003eworker = NULL;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-240-\t\tgoto err_iommu;\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-242-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:243:\tmutex_init(\u0026vdpasim-\u003emutex);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:244:\tspin_lock_init(\u0026vdpasim-\u003eiommu_lock);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-245-\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-248-\t\tgoto err_iommu;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:249:\tvdpasim-\u003evdpa.mdev = dev_attr-\u003emgmt_dev;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-250-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:251:\tvdpasim-\u003econfig = kzalloc(dev_attr-\u003econfig_size, GFP_KERNEL);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:252:\tif (!vdpasim-\u003econfig)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-253-\t\tgoto err_iommu;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-254-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:255:\tvdpasim-\u003evqs = kzalloc_objs(struct vdpasim_virtqueue, dev_attr-\u003envqs);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:256:\tif (!vdpasim-\u003evqs)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-257-\t\tgoto err_iommu;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-258-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:259:\tvdpasim-\u003eiommu = kmalloc_objs(*vdpasim-\u003eiommu, vdpasim-\u003edev_attr.nas);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:260:\tif (!vdpasim-\u003eiommu)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-261-\t\tgoto err_iommu;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-262-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:263:\tvdpasim-\u003eiommu_pt = kmalloc_objs(*vdpasim-\u003eiommu_pt,\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:264:\t\t\t\t\t vdpasim-\u003edev_attr.nas);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:265:\tif (!vdpasim-\u003eiommu_pt)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-266-\t\tgoto err_iommu;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-267-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:268:\tfor (i = 0; i \u003c vdpasim-\u003edev_attr.nas; i++) {\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:269:\t\tvhost_iotlb_init(\u0026vdpasim-\u003eiommu[i], max_iotlb_entries, 0);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:270:\t\tret = vhost_iotlb_add_range(\u0026vdpasim-\u003eiommu[i], 0, ULONG_MAX,\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-271-\t\t\t\t\t    0, VHOST_MAP_RW);\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-273-\t\t\tgoto err_iommu;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:274:\t\tvdpasim-\u003eiommu_pt[i] = true;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-275-\t}\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-277-\tfor (i = 0; i \u003c dev_attr-\u003envqs; i++)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:278:\t\tvringh_set_iotlb(\u0026vdpasim-\u003evqs[i].vring, \u0026vdpasim-\u003eiommu[0],\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:279:\t\t\t\t \u0026vdpasim-\u003eiommu_lock);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-280-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:281:\tvdpasim-\u003evdpa.vmap.dma_dev = dev;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-282-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:283:\treturn vdpasim;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-284-\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-289-}\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:290:EXPORT_SYMBOL_GPL(vdpasim_create);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-291-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:292:void vdpasim_schedule_work(struct vdpasim *vdpasim)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-293-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:294:\tkthread_queue_work(vdpasim-\u003eworker, \u0026vdpasim-\u003ework);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-295-}\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:296:EXPORT_SYMBOL_GPL(vdpasim_schedule_work);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-297-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:298:static int vdpasim_set_vq_address(struct vdpa_device *vdpa, u16 idx,\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-299-\t\t\t\t  u64 desc_area, u64 driver_area,\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-301-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:302:\tstruct vdpasim *vdpasim = vdpa_to_sim(vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:303:\tstruct vdpasim_virtqueue *vq = \u0026vdpasim-\u003evqs[idx];\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-304-\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-311-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:312:static void vdpasim_set_vq_num(struct vdpa_device *vdpa, u16 idx, u32 num)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-313-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:314:\tstruct vdpasim *vdpasim = vdpa_to_sim(vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:315:\tstruct vdpasim_virtqueue *vq = \u0026vdpasim-\u003evqs[idx];\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-316-\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-319-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:320:static u16 vdpasim_get_vq_size(struct vdpa_device *vdpa, u16 idx)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-321-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:322:\tstruct vdpasim *vdpasim = vdpa_to_sim(vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:323:\tstruct vdpasim_virtqueue *vq = \u0026vdpasim-\u003evqs[idx];\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-324-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:325:\tif (vdpasim-\u003estatus \u0026 VIRTIO_CONFIG_S_DRIVER_OK)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-326-\t\treturn vq-\u003enum;\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-330-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:331:static void vdpasim_kick_vq(struct vdpa_device *vdpa, u16 idx)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-332-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:333:\tstruct vdpasim *vdpasim = vdpa_to_sim(vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:334:\tstruct vdpasim_virtqueue *vq = \u0026vdpasim-\u003evqs[idx];\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-335-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:336:\tif (!vdpasim-\u003erunning \u0026\u0026\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:337:\t    (vdpasim-\u003estatus \u0026 VIRTIO_CONFIG_S_DRIVER_OK)) {\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:338:\t\tvdpasim-\u003epending_kick = true;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-339-\t\treturn;\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-342-\tif (vq-\u003eready)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:343:\t\tvdpasim_schedule_work(vdpasim);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-344-}\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-345-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:346:static void vdpasim_set_vq_cb(struct vdpa_device *vdpa, u16 idx,\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-347-\t\t\t      struct vdpa_callback *cb)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-348-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:349:\tstruct vdpasim *vdpasim = vdpa_to_sim(vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:350:\tstruct vdpasim_virtqueue *vq = \u0026vdpasim-\u003evqs[idx];\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-351-\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-355-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:356:static void vdpasim_set_vq_ready(struct vdpa_device *vdpa, u16 idx, bool ready)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-357-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:358:\tstruct vdpasim *vdpasim = vdpa_to_sim(vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:359:\tstruct vdpasim_virtqueue *vq = \u0026vdpasim-\u003evqs[idx];\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-360-\tbool old_ready;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-361-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:362:\tmutex_lock(\u0026vdpasim-\u003emutex);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-363-\told_ready = vq-\u003eready;\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-365-\tif (vq-\u003eready \u0026\u0026 !old_ready) {\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:366:\t\tvdpasim_queue_ready(vdpasim, idx);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-367-\t}\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:368:\tmutex_unlock(\u0026vdpasim-\u003emutex);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-369-}\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-370-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:371:static bool vdpasim_get_vq_ready(struct vdpa_device *vdpa, u16 idx)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-372-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:373:\tstruct vdpasim *vdpasim = vdpa_to_sim(vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:374:\tstruct vdpasim_virtqueue *vq = \u0026vdpasim-\u003evqs[idx];\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-375-\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-378-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:379:static int vdpasim_set_vq_state(struct vdpa_device *vdpa, u16 idx,\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-380-\t\t\t\tconst struct vdpa_vq_state *state)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-381-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:382:\tstruct vdpasim *vdpasim = vdpa_to_sim(vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:383:\tstruct vdpasim_virtqueue *vq = \u0026vdpasim-\u003evqs[idx];\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-384-\tstruct vringh *vrh = \u0026vq-\u003evring;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-385-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:386:\tmutex_lock(\u0026vdpasim-\u003emutex);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-387-\tvrh-\u003elast_avail_idx = state-\u003esplit.avail_index;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:388:\tmutex_unlock(\u0026vdpasim-\u003emutex);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-389-\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-392-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:393:static int vdpasim_get_vq_state(struct vdpa_device *vdpa, u16 idx,\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-394-\t\t\t\tstruct vdpa_vq_state *state)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-395-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:396:\tstruct vdpasim *vdpasim = vdpa_to_sim(vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:397:\tstruct vdpasim_virtqueue *vq = \u0026vdpasim-\u003evqs[idx];\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-398-\tstruct vringh *vrh = \u0026vq-\u003evring;\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-403-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:404:static int vdpasim_get_vq_stats(struct vdpa_device *vdpa, u16 idx,\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-405-\t\t\t\tstruct sk_buff *msg,\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-407-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:408:\tstruct vdpasim *vdpasim = vdpa_to_sim(vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-409-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:410:\tif (vdpasim-\u003edev_attr.get_stats)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:411:\t\treturn vdpasim-\u003edev_attr.get_stats(vdpasim, idx,\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-412-\t\t\t\t\t\t   msg, extack);\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-415-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:416:static u32 vdpasim_get_vq_align(struct vdpa_device *vdpa)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-417-{\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-420-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:421:static u32 vdpasim_get_vq_group(struct vdpa_device *vdpa, u16 idx)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-422-{\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-429-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:430:static u64 vdpasim_get_device_features(struct vdpa_device *vdpa)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-431-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:432:\tstruct vdpasim *vdpasim = vdpa_to_sim(vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-433-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:434:\treturn vdpasim-\u003edev_attr.supported_features;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-435-}\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-436-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:437:static u64 vdpasim_get_backend_features(const struct vdpa_device *vdpa)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-438-{\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-441-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:442:static int vdpasim_set_driver_features(struct vdpa_device *vdpa, u64 features)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-443-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:444:\tstruct vdpasim *vdpasim = vdpa_to_sim(vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-445-\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-449-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:450:\tvdpasim-\u003efeatures = features \u0026 vdpasim-\u003edev_attr.supported_features;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-451-\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-454-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:455:static u64 vdpasim_get_driver_features(struct vdpa_device *vdpa)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-456-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:457:\tstruct vdpasim *vdpasim = vdpa_to_sim(vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-458-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:459:\treturn vdpasim-\u003efeatures;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-460-}\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-461-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:462:static void vdpasim_set_config_cb(struct vdpa_device *vdpa,\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-463-\t\t\t\t  struct vdpa_callback *cb)\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-467-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:468:static u16 vdpasim_get_vq_num_max(struct vdpa_device *vdpa)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-469-{\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-472-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:473:static u32 vdpasim_get_device_id(struct vdpa_device *vdpa)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-474-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:475:\tstruct vdpasim *vdpasim = vdpa_to_sim(vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-476-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:477:\treturn vdpasim-\u003edev_attr.id;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-478-}\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-479-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:480:static u32 vdpasim_get_vendor_id(struct vdpa_device *vdpa)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-481-{\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-484-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:485:static u8 vdpasim_get_status(struct vdpa_device *vdpa)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-486-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:487:\tstruct vdpasim *vdpasim = vdpa_to_sim(vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-488-\tu8 status;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-489-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:490:\tmutex_lock(\u0026vdpasim-\u003emutex);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:491:\tstatus = vdpasim-\u003estatus;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:492:\tmutex_unlock(\u0026vdpasim-\u003emutex);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-493-\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-496-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:497:static void vdpasim_set_status(struct vdpa_device *vdpa, u8 status)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-498-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:499:\tstruct vdpasim *vdpasim = vdpa_to_sim(vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-500-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:501:\tmutex_lock(\u0026vdpasim-\u003emutex);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:502:\tvdpasim-\u003estatus = status;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:503:\tvdpasim-\u003erunning = (status \u0026 VIRTIO_CONFIG_S_DRIVER_OK) != 0;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:504:\tmutex_unlock(\u0026vdpasim-\u003emutex);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-505-}\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-506-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:507:static int vdpasim_compat_reset(struct vdpa_device *vdpa, u32 flags)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-508-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:509:\tstruct vdpasim *vdpasim = vdpa_to_sim(vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-510-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:511:\tmutex_lock(\u0026vdpasim-\u003emutex);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:512:\tvdpasim-\u003estatus = 0;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:513:\tvdpasim_do_reset(vdpasim, flags);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:514:\tmutex_unlock(\u0026vdpasim-\u003emutex);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-515-\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-518-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:519:static int vdpasim_reset(struct vdpa_device *vdpa)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-520-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:521:\treturn vdpasim_compat_reset(vdpa, 0);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-522-}\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-523-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:524:static int vdpasim_suspend(struct vdpa_device *vdpa)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-525-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:526:\tstruct vdpasim *vdpasim = vdpa_to_sim(vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-527-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:528:\tmutex_lock(\u0026vdpasim-\u003emutex);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:529:\tvdpasim-\u003erunning = false;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:530:\tmutex_unlock(\u0026vdpasim-\u003emutex);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-531-\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-534-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:535:static int vdpasim_resume(struct vdpa_device *vdpa)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-536-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:537:\tstruct vdpasim *vdpasim = vdpa_to_sim(vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-538-\tint i;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-539-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:540:\tmutex_lock(\u0026vdpasim-\u003emutex);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:541:\tvdpasim-\u003erunning = true;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-542-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:543:\tif (vdpasim-\u003epending_kick) {\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-544-\t\t/* Process pending descriptors */\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:545:\t\tfor (i = 0; i \u003c vdpasim-\u003edev_attr.nvqs; ++i)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:546:\t\t\tvdpasim_kick_vq(vdpa, i);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-547-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:548:\t\tvdpasim-\u003epending_kick = false;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-549-\t}\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-550-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:551:\tmutex_unlock(\u0026vdpasim-\u003emutex);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-552-\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-555-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:556:static size_t vdpasim_get_config_size(struct vdpa_device *vdpa)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-557-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:558:\tstruct vdpasim *vdpasim = vdpa_to_sim(vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-559-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:560:\treturn vdpasim-\u003edev_attr.config_size;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-561-}\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-562-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:563:static void vdpasim_get_config(struct vdpa_device *vdpa, unsigned int offset,\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-564-\t\t\t     void *buf, unsigned int len)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-565-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:566:\tstruct vdpasim *vdpasim = vdpa_to_sim(vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-567-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:568:\tif (offset + len \u003e vdpasim-\u003edev_attr.config_size)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-569-\t\treturn;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-570-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:571:\tif (vdpasim-\u003edev_attr.get_config)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:572:\t\tvdpasim-\u003edev_attr.get_config(vdpasim, vdpasim-\u003econfig);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-573-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:574:\tmemcpy(buf, vdpasim-\u003econfig + offset, len);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-575-}\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-576-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:577:static void vdpasim_set_config(struct vdpa_device *vdpa, unsigned int offset,\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-578-\t\t\t     const void *buf, unsigned int len)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-579-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:580:\tstruct vdpasim *vdpasim = vdpa_to_sim(vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-581-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:582:\tif (offset + len \u003e vdpasim-\u003edev_attr.config_size)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-583-\t\treturn;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-584-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:585:\tmemcpy(vdpasim-\u003econfig + offset, buf, len);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-586-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:587:\tif (vdpasim-\u003edev_attr.set_config)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:588:\t\tvdpasim-\u003edev_attr.set_config(vdpasim, vdpasim-\u003econfig);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-589-}\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-590-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:591:static u32 vdpasim_get_generation(struct vdpa_device *vdpa)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-592-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:593:\tstruct vdpasim *vdpasim = vdpa_to_sim(vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-594-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:595:\treturn vdpasim-\u003egeneration;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-596-}\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-597-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:598:static struct vdpa_iova_range vdpasim_get_iova_range(struct vdpa_device *vdpa)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-599-{\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-607-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:608:static int vdpasim_set_group_asid(struct vdpa_device *vdpa, unsigned int group,\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-609-\t\t\t\t  unsigned int asid)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-610-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:611:\tstruct vdpasim *vdpasim = vdpa_to_sim(vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-612-\tstruct vhost_iotlb *iommu;\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-614-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:615:\tiommu = \u0026vdpasim-\u003eiommu[asid];\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-616-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:617:\tmutex_lock(\u0026vdpasim-\u003emutex);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-618-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:619:\tfor (i = 0; i \u003c vdpasim-\u003edev_attr.nvqs; i++)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:620:\t\tif (vdpasim_get_vq_group(vdpa, i) == group)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:621:\t\t\tvringh_set_iotlb(\u0026vdpasim-\u003evqs[i].vring, iommu,\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:622:\t\t\t\t\t \u0026vdpasim-\u003eiommu_lock);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-623-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:624:\tmutex_unlock(\u0026vdpasim-\u003emutex);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-625-\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-628-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:629:static int vdpasim_set_map(struct vdpa_device *vdpa, unsigned int asid,\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-630-\t\t\t   struct vhost_iotlb *iotlb)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-631-{\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:632:\tstruct vdpasim *vdpasim = vdpa_to_sim(vdpa);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-633-\tstruct vhost_iotlb_map *map;\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-637-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:638:\tif (asid \u003e= vdpasim-\u003edev_attr.nas)\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-639-\t\treturn -EINVAL;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-640-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:641:\tspin_lock(\u0026vdpasim-\u003eiommu_lock);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-642-\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:643:\tiommu = \u0026vdpasim-\u003eiommu[asid];\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-644-\tvhost_iotlb_reset(iommu);\ndrivers/vdpa/vdpa_sim/vdpa_sim.c:645:\tvdpasim-\u003eiommu_pt[asid] = false;\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-646-\n--\ndrivers/vdpa/vdpa_sim/vdpa_sim.c-653-\t}\n\n"
}

							input: 26456
							output: 30
							thoughts: 37

Here's a summary of my thought process, as requested:

**Diving into the vDPA Simulation Black Box**

Okay, let's get down to brass tacks. I need to understand this vDPA simulation architecture better. The first place I'm going to look, and I mean really *dig* into, is the `drivers/vdpa/vdpa_sim/vdpa_sim_blk.c` file. This seems like the natural starting point for the block device simulation. I suspect this will be where the core logic for emulating a vDPA block device is implemented. It's time to analyze that code with a critical eye, really understand the mechanics, and see how it all comes together.

{
  "Expression": "vdpa_sim_blk",
  "PathPrefix": "drivers/vdpa"
}

{
  "Output": "drivers/vdpa/vdpa_sim/Makefile=3=obj-$(CONFIG_VDPA_SIM_NET) += vdpa_sim_net.o\ndrivers/vdpa/vdpa_sim/Makefile:4:obj-$(CONFIG_VDPA_SIM_BLOCK) += vdpa_sim_blk.o\n"
}

							input: 26762
							output: 32
							thoughts: 55

Okay, let's break this down.

**Investigating the Configuration and Creation of vDPA Devices**

Right, so I'm looking at `CONFIG_VDPA_SIM_BLOCK`. This likely relates to a simulated vDPA block device, which is interesting, but I need to figure out the fundamental mechanics of how these vDPA devices are created in the first place. My immediate question is whether we're dealing with a netlink-based approach for device instantiation. Specifically, is the kernel using generic netlink (`GENL_VDPA`, or something similar) to handle the creation and management of these virtual data path acceleration (vDPA) devices?

To answer that, I need to dive into the core implementation. The logical place to start digging is `drivers/vdpa/vdpa.c`. That should give me the core logic related to vDPA handling, device registration, and potentially, the netlink interface if one exists. Let's see what's in there.

{
  "Expression": "VDPA_CMD_DEV_NEW",
  "PathPrefix": "drivers/vdpa"
}

{
  "Output": "drivers/vdpa/vdpa.c=703=vdpa_dev_fill(struct vdpa_device *vdev, struct sk_buff *msg, u32 portid, u32 seq,\n--\ndrivers/vdpa/vdpa.c-712-\ndrivers/vdpa/vdpa.c:713:\thdr = genlmsg_put(msg, portid, seq, \u0026vdpa_nl_family, flags, VDPA_CMD_DEV_NEW);\ndrivers/vdpa/vdpa.c-714-\tif (!hdr)\n--\ndrivers/vdpa/vdpa.c=1507=static const struct genl_ops vdpa_nl_ops[] = {\n--\ndrivers/vdpa/vdpa.c-1513-\t{\ndrivers/vdpa/vdpa.c:1514:\t\t.cmd = VDPA_CMD_DEV_NEW,\ndrivers/vdpa/vdpa.c-1515-\t\t.doit = vdpa_nl_cmd_dev_add_set_doit,\n"
}

							input: 27328
							output: 26
							thoughts: 73

Okay, let's break this down.

**Initial Assessment of VDPA Device Creation**

Right, so I'm thinking about VDPA devices and how they're brought into existence. The gist is, we *can* create these things using the generic netlink interface, specifically with that `VDPA_CMD_DEV_NEW` command. That seems like the logical starting point, and it rings true with my understanding of netlink's role in device management in this context.

Now, the natural follow-up is, what actually *happens* after that? When we invoke `VDPA_CMD_DEV_NEW`, does the system then automatically, or via some driver-level magic, bind this newly created device to `virtio_vdpa`? That's the question I need to answer. I suspect the answer will involve either registration with the virtio driver or some form of binding process. The most likely locations for this are going to be in the device registration or probing logic.

To get the lowdown, I should probably dive into the source code. Let's see...I'll start with `drivers/vdpa/vdpa.c` since that's the more general VDPA location. If that doesn't yield immediate answers, I'll then move onto `drivers/virtio/virtio_vdpa.c`. I'm expecting to find the key details regarding the creation process and any association made between the generic VDPA framework and the virtio backend. Hopefully, one of those files will have the answers.

{
  "Expression": "virtio_vdpa",
  "PathPrefix": "drivers"
}

{
  "Output": "drivers/virtio/Makefile=12=obj-$(CONFIG_VIRTIO_INPUT) += virtio_input.o\ndrivers/virtio/Makefile:13:obj-$(CONFIG_VIRTIO_VDPA) += virtio_vdpa.o\ndrivers/virtio/Makefile-14-obj-$(CONFIG_VIRTIO_MEM) += virtio_mem.o\n--\ndrivers/virtio/virtio_vdpa.c-26-\ndrivers/virtio/virtio_vdpa.c:27:struct virtio_vdpa_device {\ndrivers/virtio/virtio_vdpa.c-28-\tstruct virtio_device vdev;\n--\ndrivers/virtio/virtio_vdpa.c-32-\ndrivers/virtio/virtio_vdpa.c:33:static inline struct virtio_vdpa_device *\ndrivers/virtio/virtio_vdpa.c:34:to_virtio_vdpa_device(struct virtio_device *dev)\ndrivers/virtio/virtio_vdpa.c-35-{\ndrivers/virtio/virtio_vdpa.c:36:\treturn container_of(dev, struct virtio_vdpa_device, vdev);\ndrivers/virtio/virtio_vdpa.c-37-}\n--\ndrivers/virtio/virtio_vdpa.c=39=static struct vdpa_device *vd_get_vdpa(struct virtio_device *vdev)\ndrivers/virtio/virtio_vdpa.c-40-{\ndrivers/virtio/virtio_vdpa.c:41:\treturn to_virtio_vdpa_device(vdev)-\u003evdpa;\ndrivers/virtio/virtio_vdpa.c-42-}\ndrivers/virtio/virtio_vdpa.c-43-\ndrivers/virtio/virtio_vdpa.c:44:static void virtio_vdpa_get(struct virtio_device *vdev, unsigned int offset,\ndrivers/virtio/virtio_vdpa.c-45-\t\t\t    void *buf, unsigned int len)\n--\ndrivers/virtio/virtio_vdpa.c-51-\ndrivers/virtio/virtio_vdpa.c:52:static void virtio_vdpa_set(struct virtio_device *vdev, unsigned int offset,\ndrivers/virtio/virtio_vdpa.c-53-\t\t\t    const void *buf, unsigned int len)\n--\ndrivers/virtio/virtio_vdpa.c-59-\ndrivers/virtio/virtio_vdpa.c:60:static u32 virtio_vdpa_generation(struct virtio_device *vdev)\ndrivers/virtio/virtio_vdpa.c-61-{\n--\ndrivers/virtio/virtio_vdpa.c-70-\ndrivers/virtio/virtio_vdpa.c:71:static u8 virtio_vdpa_get_status(struct virtio_device *vdev)\ndrivers/virtio/virtio_vdpa.c-72-{\n--\ndrivers/virtio/virtio_vdpa.c-78-\ndrivers/virtio/virtio_vdpa.c:79:static void virtio_vdpa_set_status(struct virtio_device *vdev, u8 status)\ndrivers/virtio/virtio_vdpa.c-80-{\n--\ndrivers/virtio/virtio_vdpa.c-85-\ndrivers/virtio/virtio_vdpa.c:86:static void virtio_vdpa_reset(struct virtio_device *vdev)\ndrivers/virtio/virtio_vdpa.c-87-{\n--\ndrivers/virtio/virtio_vdpa.c-92-\ndrivers/virtio/virtio_vdpa.c:93:static bool virtio_vdpa_notify(struct virtqueue *vq)\ndrivers/virtio/virtio_vdpa.c-94-{\n--\ndrivers/virtio/virtio_vdpa.c-102-\ndrivers/virtio/virtio_vdpa.c:103:static bool virtio_vdpa_notify_with_data(struct virtqueue *vq)\ndrivers/virtio/virtio_vdpa.c-104-{\n--\ndrivers/virtio/virtio_vdpa.c-113-\ndrivers/virtio/virtio_vdpa.c:114:static irqreturn_t virtio_vdpa_config_cb(void *private)\ndrivers/virtio/virtio_vdpa.c-115-{\ndrivers/virtio/virtio_vdpa.c:116:\tstruct virtio_vdpa_device *vd_dev = private;\ndrivers/virtio/virtio_vdpa.c-117-\n--\ndrivers/virtio/virtio_vdpa.c-122-\ndrivers/virtio/virtio_vdpa.c:123:static irqreturn_t virtio_vdpa_virtqueue_cb(void *private)\ndrivers/virtio/virtio_vdpa.c-124-{\n--\ndrivers/virtio/virtio_vdpa.c=130=static struct virtqueue *\ndrivers/virtio/virtio_vdpa.c:131:virtio_vdpa_setup_vq(struct virtio_device *vdev, unsigned int index,\ndrivers/virtio/virtio_vdpa.c-132-\t\t     void (*callback)(struct virtqueue *vq),\n--\ndrivers/virtio/virtio_vdpa.c-136-\tconst struct vdpa_config_ops *ops = vdpa-\u003econfig;\ndrivers/virtio/virtio_vdpa.c:137:\tbool (*notify)(struct virtqueue *vq) = virtio_vdpa_notify;\ndrivers/virtio/virtio_vdpa.c-138-\tstruct vdpa_callback cb;\n--\ndrivers/virtio/virtio_vdpa.c-156-\t\tif (ops-\u003ekick_vq_with_data)\ndrivers/virtio/virtio_vdpa.c:157:\t\t\tnotify = virtio_vdpa_notify_with_data;\ndrivers/virtio/virtio_vdpa.c-158-\t\telse\n--\ndrivers/virtio/virtio_vdpa.c-202-\t/* Setup virtqueue callback */\ndrivers/virtio/virtio_vdpa.c:203:\tcb.callback = callback ? virtio_vdpa_virtqueue_cb : NULL;\ndrivers/virtio/virtio_vdpa.c-204-\tcb.private = vq;\n--\ndrivers/virtio/virtio_vdpa.c-245-\ndrivers/virtio/virtio_vdpa.c:246:static void virtio_vdpa_del_vq(struct virtqueue *vq)\ndrivers/virtio/virtio_vdpa.c-247-{\ndrivers/virtio/virtio_vdpa.c:248:\tstruct virtio_vdpa_device *vd_dev = to_virtio_vdpa_device(vq-\u003evdev);\ndrivers/virtio/virtio_vdpa.c-249-\tstruct vdpa_device *vdpa = vd_dev-\u003evdpa;\n--\ndrivers/virtio/virtio_vdpa.c-258-\ndrivers/virtio/virtio_vdpa.c:259:static void virtio_vdpa_del_vqs(struct virtio_device *vdev)\ndrivers/virtio/virtio_vdpa.c-260-{\n--\ndrivers/virtio/virtio_vdpa.c-263-\tlist_for_each_entry_safe(vq, n, \u0026vdev-\u003evqs, list)\ndrivers/virtio/virtio_vdpa.c:264:\t\tvirtio_vdpa_del_vq(vq);\ndrivers/virtio/virtio_vdpa.c-265-}\n--\ndrivers/virtio/virtio_vdpa.c=274=create_affinity_masks(unsigned int nvecs, struct irq_affinity *affd)\n--\ndrivers/virtio/virtio_vdpa.c-327-\ndrivers/virtio/virtio_vdpa.c:328:static int virtio_vdpa_find_vqs(struct virtio_device *vdev, unsigned int nvqs,\ndrivers/virtio/virtio_vdpa.c-329-\t\t\t\tstruct virtqueue *vqs[],\n--\ndrivers/virtio/virtio_vdpa.c-332-{\ndrivers/virtio/virtio_vdpa.c:333:\tstruct virtio_vdpa_device *vd_dev = to_virtio_vdpa_device(vdev);\ndrivers/virtio/virtio_vdpa.c-334-\tstruct vdpa_device *vdpa = vd_get_vdpa(vdev);\n--\ndrivers/virtio/virtio_vdpa.c-354-\ndrivers/virtio/virtio_vdpa.c:355:\t\tvqs[i] = virtio_vdpa_setup_vq(vdev, queue_idx, vqi-\u003ecallback,\ndrivers/virtio/virtio_vdpa.c-356-\t\t\t\t\t      vqi-\u003ename, vqi-\u003ectx);\n--\ndrivers/virtio/virtio_vdpa.c-366-\ndrivers/virtio/virtio_vdpa.c:367:\tcb.callback = virtio_vdpa_config_cb;\ndrivers/virtio/virtio_vdpa.c-368-\tcb.private = vd_dev;\n--\ndrivers/virtio/virtio_vdpa.c-375-err_setup_vq:\ndrivers/virtio/virtio_vdpa.c:376:\tvirtio_vdpa_del_vqs(vdev);\ndrivers/virtio/virtio_vdpa.c-377-\tif (has_affinity)\n--\ndrivers/virtio/virtio_vdpa.c-381-\ndrivers/virtio/virtio_vdpa.c:382:static u64 virtio_vdpa_get_features(struct virtio_device *vdev)\ndrivers/virtio/virtio_vdpa.c-383-{\n--\ndrivers/virtio/virtio_vdpa.c-389-\ndrivers/virtio/virtio_vdpa.c:390:static int virtio_vdpa_finalize_features(struct virtio_device *vdev)\ndrivers/virtio/virtio_vdpa.c-391-{\n--\ndrivers/virtio/virtio_vdpa.c-399-\ndrivers/virtio/virtio_vdpa.c:400:static const char *virtio_vdpa_bus_name(struct virtio_device *vdev)\ndrivers/virtio/virtio_vdpa.c-401-{\ndrivers/virtio/virtio_vdpa.c:402:\tstruct virtio_vdpa_device *vd_dev = to_virtio_vdpa_device(vdev);\ndrivers/virtio/virtio_vdpa.c-403-\tstruct vdpa_device *vdpa = vd_dev-\u003evdpa;\n--\ndrivers/virtio/virtio_vdpa.c-407-\ndrivers/virtio/virtio_vdpa.c:408:static int virtio_vdpa_set_vq_affinity(struct virtqueue *vq,\ndrivers/virtio/virtio_vdpa.c-409-\t\t\t\t       const struct cpumask *cpu_mask)\ndrivers/virtio/virtio_vdpa.c-410-{\ndrivers/virtio/virtio_vdpa.c:411:\tstruct virtio_vdpa_device *vd_dev = to_virtio_vdpa_device(vq-\u003evdev);\ndrivers/virtio/virtio_vdpa.c-412-\tstruct vdpa_device *vdpa = vd_dev-\u003evdpa;\n--\ndrivers/virtio/virtio_vdpa.c=422=static const struct cpumask *\ndrivers/virtio/virtio_vdpa.c:423:virtio_vdpa_get_vq_affinity(struct virtio_device *vdev, int index)\ndrivers/virtio/virtio_vdpa.c-424-{\n--\ndrivers/virtio/virtio_vdpa.c-433-\ndrivers/virtio/virtio_vdpa.c:434:static const struct virtio_config_ops virtio_vdpa_config_ops = {\ndrivers/virtio/virtio_vdpa.c:435:\t.get\t\t= virtio_vdpa_get,\ndrivers/virtio/virtio_vdpa.c:436:\t.set\t\t= virtio_vdpa_set,\ndrivers/virtio/virtio_vdpa.c:437:\t.generation\t= virtio_vdpa_generation,\ndrivers/virtio/virtio_vdpa.c:438:\t.get_status\t= virtio_vdpa_get_status,\ndrivers/virtio/virtio_vdpa.c:439:\t.set_status\t= virtio_vdpa_set_status,\ndrivers/virtio/virtio_vdpa.c:440:\t.reset\t\t= virtio_vdpa_reset,\ndrivers/virtio/virtio_vdpa.c:441:\t.find_vqs\t= virtio_vdpa_find_vqs,\ndrivers/virtio/virtio_vdpa.c:442:\t.del_vqs\t= virtio_vdpa_del_vqs,\ndrivers/virtio/virtio_vdpa.c:443:\t.get_features\t= virtio_vdpa_get_features,\ndrivers/virtio/virtio_vdpa.c:444:\t.finalize_features = virtio_vdpa_finalize_features,\ndrivers/virtio/virtio_vdpa.c:445:\t.bus_name\t= virtio_vdpa_bus_name,\ndrivers/virtio/virtio_vdpa.c:446:\t.set_vq_affinity = virtio_vdpa_set_vq_affinity,\ndrivers/virtio/virtio_vdpa.c:447:\t.get_vq_affinity = virtio_vdpa_get_vq_affinity,\ndrivers/virtio/virtio_vdpa.c-448-};\ndrivers/virtio/virtio_vdpa.c-449-\ndrivers/virtio/virtio_vdpa.c:450:static void virtio_vdpa_release_dev(struct device *_d)\ndrivers/virtio/virtio_vdpa.c-451-{\n--\ndrivers/virtio/virtio_vdpa.c-453-\t       container_of(_d, struct virtio_device, dev);\ndrivers/virtio/virtio_vdpa.c:454:\tstruct virtio_vdpa_device *vd_dev =\ndrivers/virtio/virtio_vdpa.c:455:\t       container_of(vdev, struct virtio_vdpa_device, vdev);\ndrivers/virtio/virtio_vdpa.c-456-\n--\ndrivers/virtio/virtio_vdpa.c-459-\ndrivers/virtio/virtio_vdpa.c:460:static int virtio_vdpa_probe(struct vdpa_device *vdpa)\ndrivers/virtio/virtio_vdpa.c-461-{\ndrivers/virtio/virtio_vdpa.c-462-\tconst struct vdpa_config_ops *ops = vdpa-\u003econfig;\ndrivers/virtio/virtio_vdpa.c:463:\tstruct virtio_vdpa_device *vd_dev, *reg_dev = NULL;\ndrivers/virtio/virtio_vdpa.c-464-\tint ret = -EINVAL;\n--\ndrivers/virtio/virtio_vdpa.c-471-\t\t\t\t  vdpa_get_map(vdpa).dma_dev;\ndrivers/virtio/virtio_vdpa.c:472:\tvd_dev-\u003evdev.dev.release = virtio_vdpa_release_dev;\ndrivers/virtio/virtio_vdpa.c:473:\tvd_dev-\u003evdev.config = \u0026virtio_vdpa_config_ops;\ndrivers/virtio/virtio_vdpa.c-474-\tvd_dev-\u003evdev.map = vdpa-\u003emap;\n--\ndrivers/virtio/virtio_vdpa.c-498-\ndrivers/virtio/virtio_vdpa.c:499:static void virtio_vdpa_remove(struct vdpa_device *vdpa)\ndrivers/virtio/virtio_vdpa.c-500-{\ndrivers/virtio/virtio_vdpa.c:501:\tstruct virtio_vdpa_device *vd_dev = vdpa_get_drvdata(vdpa);\ndrivers/virtio/virtio_vdpa.c-502-\n--\ndrivers/virtio/virtio_vdpa.c-505-\ndrivers/virtio/virtio_vdpa.c:506:static struct vdpa_driver virtio_vdpa_driver = {\ndrivers/virtio/virtio_vdpa.c-507-\t.driver = {\ndrivers/virtio/virtio_vdpa.c:508:\t\t.name\t= \"virtio_vdpa\",\ndrivers/virtio/virtio_vdpa.c-509-\t},\ndrivers/virtio/virtio_vdpa.c:510:\t.probe\t= virtio_vdpa_probe,\ndrivers/virtio/virtio_vdpa.c:511:\t.remove = virtio_vdpa_remove,\ndrivers/virtio/virtio_vdpa.c-512-};\ndrivers/virtio/virtio_vdpa.c-513-\ndrivers/virtio/virtio_vdpa.c:514:module_vdpa_driver(virtio_vdpa_driver);\ndrivers/virtio/virtio_vdpa.c-515-\n"
}

							input: 32253
							output: 39
							thoughts: 1884

**Analysis of virtio_blk Driver Bug and Reachability for Fuzzing**

Okay, so looking at this code, it appears `vdpa_sim_blk` creates a vDPA device that simulates a virtio-blk device. When a vdpa device is managed by `virtio_vdpa`, `virtio_vdpa_probe` calls `register_virtio_device(&vd_dev->vdev)`. That, in turn, registers the device on the `virtio_bus`. When that device gets matched to `virtio_blk`, `virtblk_probe` is called. The instructions specifically state that drivers accessible via virtual buses like virtio are fair game.

I'm starting to zero in on this `virtblk_probe` function. I need to figure out if there's a scenario where it can fail and hit the `out_cleanup_disk` path. Looking closely at `virtblk_probe`, I see `device_add_disk()` is called, and if *that* fails, we jump to `out_cleanup_disk`. I also notice a commit that adds `virtio_reset_device(vdev)` *before* `put_disk(vblk->disk)`.

Aha! Now I see the light, that commit fixed a bug related to `device_add_disk` failing! Before the patch, `virtio_device_ready(vdev)` was called, marking the device as `DRIVER_OK`, potentially with active interrupts/callbacks/virtqueues. If `device_add_disk` failed *after* that, the device would be partially set up, but the cleanup path didn't stop the virtqueues or clear `DRIVER_OK`! Without the `virtio_reset_device`, this could lead to issues.

Now, the crucial question is whether this code path, specifically the error handling in `virtblk_probe`, is actually reachable. I have to ensure this doesn't fall into the negative criteria listed.

1. This isn't a non-kernel, non-executable change. It's C code within the `virtio_blk` driver.
2. It's not structurally unreachable hardware. Virtio is *explicitly* mentioned as reachable via virtual buses within the positive criteria.
3. This isn't a driver teardown callback (.remove, .shutdown, pci_unregister_driver) executed only during physical PCI hot-unplug or manual sysfs driver unbinding. This is error handling *during* probe, not teardown.

So, to be clear, the error cleanup in `virtblk_probe` is reachable.

How might `device_add_disk` fail? Well, fault injection is a big one. Also, memory allocation failures, duplicate sysfs names, or failures if `CONFIG_BLK_DEV_ZONED` is enabled and `blk_revalidate_disk_zones()` fails. Syzkaller is known to use fault injection, especially during driver probe! I should look for those.

Can syzkaller *actually* fuzz `virtio_blk`? Can it create virtio_blk devices or vdpa devices? Yes! Through vdpa netlink (`VDPA_CMD_DEV_NEW`) to instantiate a `vdpa_sim_blk` device and bind `virtio_vdpa` to it, through fault injection on boot/module loading, or by using vdpa! Also, the prompt does not exclude userspace interaction with the driver via the driver core sysfs.

In short: Virtio is a *reachable* virtual bus, `virtio_blk` is the canonical virtio block driver, and the specific code path that this patch fixes is reachable through various scenarios (particularly error handling with tools like Syzkaller).

Finally, I will check the area in `drivers/block/virtio_blk.c` around `virtblk_probe` for focus symbols to be considered.

{
  "File": "drivers/block/virtio_blk.c",
  "FirstLine": 1435,
  "LineCount": 90
}

{
  "Contents": "1435:\t\treturn 0;\n1436:\t}\n1437:\t\n1438:\tstatic int virtblk_probe(struct virtio_device *vdev)\n1439:\t{\n1440:\t\tstruct virtio_blk *vblk;\n1441:\t\tstruct queue_limits lim = {\n1442:\t\t\t.features\t\t= BLK_FEAT_ROTATIONAL,\n1443:\t\t\t.logical_block_size\t= SECTOR_SIZE,\n1444:\t\t};\n1445:\t\tint err, index;\n1446:\t\tunsigned int queue_depth;\n1447:\t\n1448:\t\tif (!vdev-\u003econfig-\u003eget) {\n1449:\t\t\tdev_err(\u0026vdev-\u003edev, \"%s failure: config access disabled\\n\",\n1450:\t\t\t\t__func__);\n1451:\t\t\treturn -EINVAL;\n1452:\t\t}\n1453:\t\n1454:\t\terr = ida_alloc_range(\u0026vd_index_ida, 0,\n1455:\t\t\t\t      minor_to_index(1 \u003c\u003c MINORBITS) - 1, GFP_KERNEL);\n1456:\t\tif (err \u003c 0)\n1457:\t\t\tgoto out;\n1458:\t\tindex = err;\n1459:\t\n1460:\t\tvdev-\u003epriv = vblk = kmalloc_obj(*vblk);\n1461:\t\tif (!vblk) {\n1462:\t\t\terr = -ENOMEM;\n1463:\t\t\tgoto out_free_index;\n1464:\t\t}\n1465:\t\n1466:\t\tmutex_init(\u0026vblk-\u003evdev_mutex);\n1467:\t\n1468:\t\tvblk-\u003evdev = vdev;\n1469:\t\n1470:\t\tINIT_WORK(\u0026vblk-\u003econfig_work, virtblk_config_changed_work);\n1471:\t\n1472:\t\terr = init_vq(vblk);\n1473:\t\tif (err)\n1474:\t\t\tgoto out_free_vblk;\n1475:\t\n1476:\t\t/* Default queue sizing is to fill the ring. */\n1477:\t\tif (!virtblk_queue_depth) {\n1478:\t\t\tqueue_depth = vblk-\u003evqs[0].vq-\u003enum_free;\n1479:\t\t\t/* ... but without indirect descs, we use 2 descs per req */\n1480:\t\t\tif (!virtio_has_feature(vdev, VIRTIO_RING_F_INDIRECT_DESC))\n1481:\t\t\t\tqueue_depth /= 2;\n1482:\t\t} else {\n1483:\t\t\tqueue_depth = virtblk_queue_depth;\n1484:\t\t}\n1485:\t\n1486:\t\tmemset(\u0026vblk-\u003etag_set, 0, sizeof(vblk-\u003etag_set));\n1487:\t\tvblk-\u003etag_set.ops = \u0026virtio_mq_ops;\n1488:\t\tvblk-\u003etag_set.queue_depth = queue_depth;\n1489:\t\tvblk-\u003etag_set.numa_node = NUMA_NO_NODE;\n1490:\t\tvblk-\u003etag_set.cmd_size =\n1491:\t\t\tsizeof(struct virtblk_req) +\n1492:\t\t\tsizeof(struct scatterlist) * VIRTIO_BLK_INLINE_SG_CNT;\n1493:\t\tvblk-\u003etag_set.driver_data = vblk;\n1494:\t\tvblk-\u003etag_set.nr_hw_queues = vblk-\u003enum_vqs;\n1495:\t\tvblk-\u003etag_set.nr_maps = 1;\n1496:\t\tif (vblk-\u003eio_queues[HCTX_TYPE_POLL])\n1497:\t\t\tvblk-\u003etag_set.nr_maps = 3;\n1498:\t\n1499:\t\terr = blk_mq_alloc_tag_set(\u0026vblk-\u003etag_set);\n1500:\t\tif (err)\n1501:\t\t\tgoto out_free_vq;\n1502:\t\n1503:\t\terr = virtblk_read_limits(vblk, \u0026lim);\n1504:\t\tif (err)\n1505:\t\t\tgoto out_free_tags;\n1506:\t\n1507:\t\tif (virtblk_get_cache_mode(vdev))\n1508:\t\t\tlim.features |= BLK_FEAT_WRITE_CACHE;\n1509:\t\n1510:\t\tvblk-\u003edisk = blk_mq_alloc_disk(\u0026vblk-\u003etag_set, \u0026lim, vblk);\n1511:\t\tif (IS_ERR(vblk-\u003edisk)) {\n1512:\t\t\terr = PTR_ERR(vblk-\u003edisk);\n1513:\t\t\tgoto out_free_tags;\n1514:\t\t}\n1515:\t\n1516:\t\tvirtblk_name_format(\"vd\", index, vblk-\u003edisk-\u003edisk_name, DISK_NAME_LEN);\n1517:\t\n1518:\t\tvblk-\u003edisk-\u003emajor = major;\n1519:\t\tvblk-\u003edisk-\u003efirst_minor = index_to_minor(index);\n1520:\t\tvblk-\u003edisk-\u003eminors = 1 \u003c\u003c PART_BITS;\n1521:\t\tvblk-\u003edisk-\u003eprivate_data = vblk;\n1522:\t\tvblk-\u003edisk-\u003efops = \u0026virtblk_fops;\n1523:\t\tvblk-\u003eindex = index;\n1524:\t\n"
}

							input: 36473
							output: 29
							thoughts: 25

Okay, here's my take on those thoughts, tailored for an expert audience:

**Diving into the Virtio Block Kconfig**

Alright, time to get my hands dirty with the `virtio_blk` Kconfig. I need to understand its configuration. First things first, I need to pinpoint exactly *where* `CONFIG_VIRTIO_BLK` is defined within the Kconfig files. Knowing the definition is crucial for tracing its dependencies, possible default settings, and potential build options. Gotta start there.

{
  "Expression": "config VIRTIO_BLK",
  "PathPrefix": "drivers/block"
}

{
  "Output": "drivers/block/Kconfig=286=config XEN_BLKDEV_BACKEND\n--\ndrivers/block/Kconfig-306-\ndrivers/block/Kconfig:307:config VIRTIO_BLK\ndrivers/block/Kconfig-308-\ttristate \"Virtio block driver\"\n"
}

							input: 36723
							output: 34
							thoughts: 19

Okay, let's dive into this. Here's my thought process on the matter:

**Analyzing Block Driver Configuration in Kconfig**

Alright, time to get my hands dirty. I'm going to jump straight into the heart of the matter – the `drivers/block/Kconfig` file. Specifically, I'm focusing around line 307. I know this file is where the configuration options for block device drivers are defined, so I'm expecting to find some interesting logic there. I'm hoping to get a clearer picture of how specific drivers are selected, what dependencies they have, and perhaps even some hints about the overall design philosophy regarding block device handling in this kernel version. I'm keen to see the structure, conditionals, and any macros that are employed to determine which drivers are compiled into the image and how they relate to the underlying hardware.

{
  "File": "drivers/block/Kconfig",
  "FirstLine": 305,
  "LineCount": 20
}

{
  "Contents": " 305:\t\n 306:\t\n 307:\tconfig VIRTIO_BLK\n 308:\t\ttristate \"Virtio block driver\"\n 309:\t\tdepends on VIRTIO\n 310:\t\tselect SG_POOL\n 311:\t\thelp\n 312:\t\t  This is the virtual block driver for virtio.  It can be used with\n 313:\t          QEMU based VMMs (like KVM or Xen).  Say Y or M.\n 314:\t\n 315:\tconfig BLK_DEV_RBD\n 316:\t\ttristate \"Rados block device (RBD)\"\n 317:\t\tdepends on INET \u0026\u0026 BLOCK\n 318:\t\tselect CEPH_LIB\n 319:\t\thelp\n 320:\t\t  Say Y here if you want include the Rados block device, which stripes\n 321:\t\t  a block device over objects stored in the Ceph distributed object\n 322:\t\t  store.\n 323:\t\n 324:\t\t  More information at http://ceph.newdream.net/.\n"
}

							input: 37250
							output: 31
							thoughts: 286

**Analyzing Virtio Block Configuration**

Okay, so I'm looking at `CONFIG_VIRTIO_BLK`, and it's clear that it depends on `CONFIG_VIRTIO`. That's the starting point. Now, the key here is to see if either of them, `VIRTIO_BLK` or `VIRTIO`, has any other dependencies that I need to be aware of. I'll need to double-check the `drivers/block/Kconfig` file. Right, I see, `depends on VIRTIO` again. That confirms the initial dependency. And `select SG_POOL`, that's noted.

Now, let's cast a wider net. I should identify all the related configs. Let's make sure I'm not missing anything. I've got `VIRTIO` and `VIRTIO_BLK` already, and then I see `BLK_DEV_ZONED` might be relevant since zoned check is right above `out_cleanup_disk`. Looking at the code: `if (IS_ENABLED(CONFIG_BLK_DEV_ZONED) && (lim.features & BLK_FEAT_ZONED))`. I should make a note of this.

Ah, and I almost forgot about `VIRTIO_VDPA` and `VDPA_SIM_BLOCK`. Those enable the dynamic testing of virtio-blk via the vDPA simulator. Good, so the takeaway here is, for enabling, it's `VIRTIO_BLK`, and `VIRTIO`, obviously.

Hold on, I need to check something important. I'm wondering if `virtblk_probe` is something I should include in `FocusSymbols`. And I'm also wondering if `virtio_reset_device` should be considered too.

Wait a second! I'm forgetting something. `virtio_reset_device` is in `drivers/virtio/virtio.c`. Let me refresh my memory and check what `virtio_reset_device` actually does.

{
  "Expression": "void virtio_reset_device",
  "PathPrefix": "drivers/virtio"
}

{
  "Output": "drivers/virtio/virtio.c=204=static int virtio_features_ok(struct virtio_device *dev)\n--\ndrivers/virtio/virtio.c-252- * */\ndrivers/virtio/virtio.c:253:void virtio_reset_device(struct virtio_device *dev)\ndrivers/virtio/virtio.c-254-{\n"
}

							input: 38114
							output: 153
							thoughts: 560

**My Analysis of the Fuzzing Strategy**

Okay, let's break this down from a fuzzing perspective. `virtio_reset_device` is the generic reset function for all virtio devices – we know that. Now, the key is understanding how to apply the "WorthFuzzing=true" principle and focus our fuzzer effectively, per Section 4's guidance. I've been tasked with analyzing this patch, and I need to determine the right approach.

The critical function modified by this patch is `virtblk_probe`. Is it ubiquitous? No, thankfully, it's specific to the virtio_blk driver's probing process. That's a good start. But is it a non-static symbol? I have to confirm that `virtblk_probe` *is* a distinct symbol in vmlinux, and it seems like it is, since it's defined as `static int virtblk_probe(struct virtio_device *vdev)` in `drivers/block/virtio_blk.c`. In the Linux kernel, static functions in `.c` files have symbol addresses in `kallsyms` and `vmlinux`, unless inlined. Because it's a probe callback pointer, assigned to `.probe = virtblk_probe` in `virtio_driver`, it *cannot* be inlined. So, yes, it's a distinct symbol.

Now, let's verify that the patch makes sense in the larger context. Looking at the code snippet, I see that the patch invokes `virtio_reset_device(vdev)` within `virtblk_probe`'s error cleanup path, specifically if `device_add_disk()` or `blk_revalidate_disk_zones()` fails. This implies that the device had been made ready through `virtio_device_ready(vdev)`. So, this `virtio_reset_device` call is there to ensure the virtio device is properly reset after being enabled, in the case of a disk initialization failure.

Based on this analysis, the reasoning is sound. The patch addresses a missing error-cleanup device reset (`virtio_reset_device`) within `virtblk_probe()` when disk initialization fails, after the device has been readied. Virtio block devices are common in virtualized environments (QEMU, vDPA/virtio-vdpa), and can be probed at boot or dynamically, making this error path reachable under fault injection or device setup failure. Therefore, the setup for `WorthFuzzing=true` is valid.

The `FocusSymbols` should be set to `["virtblk_probe"]`. The `EnableConfigs` should include `["VIRTIO_BLK", "VIRTIO"]`.

I'm confident in my analysis. It's time to call `set-results`.

{
  "EnableConfigs": [
    "VIRTIO_BLK",
    "VIRTIO"
  ],
  "FocusSymbols": [
    "virtblk_probe"
  ],
  "Reasoning": "The patch modifies the probe error handling path in the virtio_blk driver, adding a call to virtio_reset_device() in virtblk_probe() if blk_revalidate_disk_zones() or device_add_disk() fails after virtio_device_ready() has been called. Virtio drivers operate on virtual devices accessible in standard QEMU environments (and dynamically via vDPA simulation), and this error path is reachable during device initialization under error conditions or fault injection.",
  "WorthFuzzing": true
}

{
  "EnableConfigs": [
    "VIRTIO_BLK",
    "VIRTIO"
  ],
  "FocusSymbols": [
    "virtblk_probe"
  ],
  "Reasoning": "The patch modifies the probe error handling path in the virtio_blk driver, adding a call to virtio_reset_device() in virtblk_probe() if blk_revalidate_disk_zones() or device_add_disk() fails after virtio_device_ready() has been called. Virtio drivers operate on virtual devices accessible in standard QEMU environments (and dynamically via vDPA simulation), and this error path is reachable during device initialization under error conditions or fault injection.",
  "WorthFuzzing": true
}

{
  "WorthFuzzing": true
}

{
  "KMSANReasoning": "The patch inserts a call to virtio_reset_device(vdev) in the error cleanup path (out_cleanup_disk) of virtblk_probe(). When probe fails after virtio_device_ready() was already invoked, resetting the device stops virtqueue operations and hardware interrupts before freeing the tag set, virtqueues, and disk structures.\n\nThis change exclusively addresses device teardown order and avoids potential use-after-free or race conditions where host/device accesses freed structures, which falls squarely within the scope of KASAN. The patch does not touch, allocate, or read any uninitialized memory, does not alter data boundaries or control flow based on uninitialized fields, and does not leak kernel memory to user space. Therefore, a dedicated KMSAN fuzzing session is not warranted.",
  "NeedsKMSAN": false
}

You are an expert Linux kernel security engineer specializing in kernel memory
error detectors (KASAN and KMSAN). Your job is to review the provided patch series and
determine if the code changes justify spawning a dedicated KMSAN (KernelMemorySanitizer)
fuzzing session in addition to standard KASAN fuzzing.

CRITICAL DISTINCTION BETWEEN KASAN AND KMSAN:
- Standard KASAN kernel builds (upstream-apparmor-kasan.config) already enable
  a comprehensive suite of debugging tools and sanitizers, including KASAN
  (out-of-bounds accesses, use-after-free, double free, invalid free), LOCKDEP
  (locking bugs and deadlocks), UB-sanitizers, and memory corruption checks.
- KMSAN (KernelMemorySanitizer) detects reads of UNINITIALIZED memory (stack, heap,
  or page allocations) and kernel-to-user memory info-leaks.

Rule: THERE IS NO SENSE IN RUNNING A KMSAN SESSION IF A BUG CAN BE CAUGHT BY KASAN,
LOCKDEP, OR OTHER STANDARD BUG DETECTORS.
A dedicated KMSAN fuzzing session incurs significant resource costs. You must ONLY
set NeedsKMSAN=true if the code changes introduce or expose UNINITIALIZED MEMORY risks
that are detected ONLY by KMSAN.

Look holistically at the patch series and surrounding code. Even if no direct
uninitialized field accesses or new buffer allocations are added in the diff itself,
a patch may alter control flow, bounds checking, or data length calculations in ways
that change how the rest of the code operates on existing buffers (e.g. allowing
uninitialized stack/heap memory to be read, copied to user space, or used in control
flow). Do not hesitate to use your code access tools to inspect the surrounding code,
called functions, and callers.

Set NeedsKMSAN=true ONLY IF the patch introduces or modifies:
1. Kernel structures sent to user space (via copy_to_user, put_user, netlink skb
   attributes, ioctl output arguments, socket options, or BPF buffers) where fields
   or structure padding might not be fully initialized/zeroed.
2. Conditional logic or branching that depends on potentially uninitialized variables
   or struct fields.
3. Allocation or initialization of complex data structures where uninitialized fields
   could be read later in reachable code paths.
4. Bounds checks, lengths, or logic in a way that allows surrounding code to access
   uninitialized bytes of existing buffers.

Set NeedsKMSAN=false IF:
- The code changes primarily risk out-of-bounds access, array overflows, NULL pointer
  dereferences, locking deadlocks, or use-after-free bugs (these are already caught
  by KASAN, LOCKDEP, or standard bug detectors).
- All stack/heap structures touched or introduced by the patch are fully zeroed
  or initialized (e.g. using = {0}, memset, kzalloc) before being read or copied.
- The patch does not introduce any risk of uninitialized memory usage or info-leaks.

Use your code access tools to inspect the surrounding code if necessary, then provide
detailed KMSANReasoning contrasting KASAN vs KMSAN applicability for this patch.
Prefer calling several tools at the same time to save round-trips.


Use set-results tool to provide results of the analysis.
It must be called exactly once before the final reply.
Ignore results of this tool.

Target architecture: amd64

For your convenience, here is the diff of the changes:
commit f6c61baa8acd35abd69257c2e15ebb9cf04f3e7f
Author: syz-cluster <triage@syzkaller.com>
Date:   Fri Sep 25 04:38:31 2026 +0000

    syz-cluster: applied patch under review

diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c
index 32bf3ba07a9dc..ed97dafebe164 100644
--- a/drivers/block/virtio_blk.c
+++ b/drivers/block/virtio_blk.c
@@ -1547,6 +1547,7 @@ static int virtblk_probe(struct virtio_device *vdev)
 	return 0;
 
 out_cleanup_disk:
+	virtio_reset_device(vdev);
 	put_disk(vblk->disk);
 out_free_tags:
 	blk_mq_free_tag_set(&vblk->tag_set);

							input: 2055
							output: 39
							thoughts: 342

**KMSAN Fuzzing Necessity Evaluation**

Okay, so I need to decide if this patch series warrants a dedicated KMSAN fuzzing session, beyond what KASAN already provides. Let's do a quick risk analysis. The task is pretty straightforward: code review of a Linux kernel patch to determine if KMSAN is necessary. It's essentially defensive software testing, a sanitizer triage exercise. The classification is likely benign or low severity, falling under defensive QA, fuzzing configuration, or standard kernel patch review. No malware or exploit generation is involved, so that simplifies things.

Now, to the heart of the matter – inspecting the patch itself.

Looking at the diff, it seems we're adding `virtio_reset_device(vdev)` within the `virtblk_probe` function, specifically in the cleanup path. A quick search around the area:

```diff
diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c
index 32bf3ba07a9dc..ed97dafebe164 100644
--- a/drivers/block/virtio_blk.c
+++ b/drivers/block/virtio_blk.c
@@ -1547,6 +1547,7 @@ static int virtblk_probe(struct virtio_device *vdev)
 	return 0;
 
 out_cleanup_disk:
+	virtio_reset_device(vdev);
 	put_disk(vblk->disk);
 out_free_tags:
 	blk_mq_free_tag_set(&vblk->tag_set);
```

I'll need to read the surrounding code in `drivers/block/virtio_blk.c` around line 1547 to understand the context and the potential impact of this addition. I'll need to use either `read-file` or `grepper` to pull that in. Understanding the interaction with the device reset is key.

{
  "File": "drivers/block/virtio_blk.c",
  "FirstLine": 1500,
  "LineCount": 70
}

{
  "Contents": "1500:\t\tif (err)\n1501:\t\t\tgoto out_free_vq;\n1502:\t\n1503:\t\terr = virtblk_read_limits(vblk, \u0026lim);\n1504:\t\tif (err)\n1505:\t\t\tgoto out_free_tags;\n1506:\t\n1507:\t\tif (virtblk_get_cache_mode(vdev))\n1508:\t\t\tlim.features |= BLK_FEAT_WRITE_CACHE;\n1509:\t\n1510:\t\tvblk-\u003edisk = blk_mq_alloc_disk(\u0026vblk-\u003etag_set, \u0026lim, vblk);\n1511:\t\tif (IS_ERR(vblk-\u003edisk)) {\n1512:\t\t\terr = PTR_ERR(vblk-\u003edisk);\n1513:\t\t\tgoto out_free_tags;\n1514:\t\t}\n1515:\t\n1516:\t\tvirtblk_name_format(\"vd\", index, vblk-\u003edisk-\u003edisk_name, DISK_NAME_LEN);\n1517:\t\n1518:\t\tvblk-\u003edisk-\u003emajor = major;\n1519:\t\tvblk-\u003edisk-\u003efirst_minor = index_to_minor(index);\n1520:\t\tvblk-\u003edisk-\u003eminors = 1 \u003c\u003c PART_BITS;\n1521:\t\tvblk-\u003edisk-\u003eprivate_data = vblk;\n1522:\t\tvblk-\u003edisk-\u003efops = \u0026virtblk_fops;\n1523:\t\tvblk-\u003eindex = index;\n1524:\t\n1525:\t\t/* If disk is read-only in the host, the guest should obey */\n1526:\t\tif (virtio_has_feature(vdev, VIRTIO_BLK_F_RO))\n1527:\t\t\tset_disk_ro(vblk-\u003edisk, 1);\n1528:\t\n1529:\t\tvirtblk_update_capacity(vblk, false);\n1530:\t\tvirtio_device_ready(vdev);\n1531:\t\n1532:\t\t/*\n1533:\t\t * All steps that follow use the VQs therefore they need to be\n1534:\t\t * placed after the virtio_device_ready() call above.\n1535:\t\t */\n1536:\t\tif (IS_ENABLED(CONFIG_BLK_DEV_ZONED) \u0026\u0026\n1537:\t\t    (lim.features \u0026 BLK_FEAT_ZONED)) {\n1538:\t\t\terr = blk_revalidate_disk_zones(vblk-\u003edisk);\n1539:\t\t\tif (err)\n1540:\t\t\t\tgoto out_cleanup_disk;\n1541:\t\t}\n1542:\t\n1543:\t\terr = device_add_disk(\u0026vdev-\u003edev, vblk-\u003edisk, virtblk_attr_groups);\n1544:\t\tif (err)\n1545:\t\t\tgoto out_cleanup_disk;\n1546:\t\n1547:\t\treturn 0;\n1548:\t\n1549:\tout_cleanup_disk:\n1550:\t\tvirtio_reset_device(vdev);\n1551:\t\tput_disk(vblk-\u003edisk);\n1552:\tout_free_tags:\n1553:\t\tblk_mq_free_tag_set(\u0026vblk-\u003etag_set);\n1554:\tout_free_vq:\n1555:\t\tvdev-\u003econfig-\u003edel_vqs(vdev);\n1556:\t\tkfree(vblk-\u003evqs);\n1557:\tout_free_vblk:\n1558:\t\tkfree(vblk);\n1559:\tout_free_index:\n1560:\t\tida_free(\u0026vd_index_ida, index);\n1561:\tout:\n1562:\t\treturn err;\n1563:\t}\n1564:\t\n1565:\tstatic void virtblk_remove(struct virtio_device *vdev)\n1566:\t{\n1567:\t\tstruct virtio_blk *vblk = vdev-\u003epriv;\n1568:\t\n1569:\t\t/* Make sure no work handler is accessing the device. */\n"
}

							input: 3974
							output: 39
							thoughts: 222

**Addressing a Potential Race Condition in the Virtio Block Driver**

Okay, let's break this down. Line 1530 in `virtblk_probe` is where things get interesting. We have `virtio_device_ready(vdev)`. So, the device is considered ready at this point, but if either `blk_revalidate_disk_zones` or `device_add_disk` hits a snag, we're jumping straight to `out_cleanup_disk`. Now, in the *past* implementation, at `out_cleanup_disk`, we'd first do a `put_disk(vblk->disk)`, and then we'd go on to free up the tag set, the `del_vqs`, etc. However, this raises a red flag. Because `virtio_device_ready(vdev)` had already been called, the device is now in an active state.

Here's the problem: if an error happens *after* the device is ready, it's not being properly reset *before* we start tearing down the virtqueues and freeing the tag set. That is a use-after-free situation, waiting to happen. We're potentially dealing with virtqueue interrupts or host activity trying to access memory that's already been freed. This results in improper device cleanup.

The fix? Simple, elegant. We need to call `virtio_reset_device(vdev);` *before* we start cleaning up. This will properly reset the device, ensuring it stops processing queues and sending interrupts *before* we start dismantling things. It's a critical safety net. Now I'm going to look at `virtblk_remove` to see where else we need to take care.

{
  "File": "drivers/block/virtio_blk.c",
  "FirstLine": 1565,
  "LineCount": 40
}

{
  "Contents": "1565:\tstatic void virtblk_remove(struct virtio_device *vdev)\n1566:\t{\n1567:\t\tstruct virtio_blk *vblk = vdev-\u003epriv;\n1568:\t\n1569:\t\t/* Make sure no work handler is accessing the device. */\n1570:\t\tflush_work(\u0026vblk-\u003econfig_work);\n1571:\t\n1572:\t\tdel_gendisk(vblk-\u003edisk);\n1573:\t\tblk_mq_free_tag_set(\u0026vblk-\u003etag_set);\n1574:\t\n1575:\t\tmutex_lock(\u0026vblk-\u003evdev_mutex);\n1576:\t\n1577:\t\t/* Stop all the virtqueues. */\n1578:\t\tvirtio_reset_device(vdev);\n1579:\t\n1580:\t\t/* Virtqueues are stopped, nothing can use vblk-\u003evdev anymore. */\n1581:\t\tvblk-\u003evdev = NULL;\n1582:\t\n1583:\t\tvdev-\u003econfig-\u003edel_vqs(vdev);\n1584:\t\tkfree(vblk-\u003evqs);\n1585:\t\n1586:\t\tmutex_unlock(\u0026vblk-\u003evdev_mutex);\n1587:\t\n1588:\t\tput_disk(vblk-\u003edisk);\n1589:\t}\n1590:\t\n1591:\tstatic int virtblk_freeze_priv(struct virtio_device *vdev)\n1592:\t{\n1593:\t\tstruct virtio_blk *vblk = vdev-\u003epriv;\n1594:\t\tstruct request_queue *q = vblk-\u003edisk-\u003equeue;\n1595:\t\tunsigned int memflags;\n1596:\t\n1597:\t\t/* Ensure no requests in virtqueues before deleting vqs. */\n1598:\t\tmemflags = blk_mq_freeze_queue(q);\n1599:\t\tblk_mq_quiesce_queue_nowait(q);\n1600:\t\tblk_mq_unfreeze_queue(q, memflags);\n1601:\t\n1602:\t\t/* Ensure we don't receive any more interrupts */\n1603:\t\tvirtio_reset_device(vdev);\n1604:\t\n"
}

							input: 5210
							output: 190
							thoughts: 869

**KMSAN Assessment: virtio_blk.c patch**

Okay, let's break this down. The patch adds `virtio_reset_device(vdev)` to the error handling path (`out_cleanup_disk`) within `virtblk_probe`. My primary concern, of course, is whether this introduces or exposes any uninitialized memory vulnerabilities.

First, I need to methodically check the criteria. Am I sending any kernel structures to user space? No, this is all internal probe error handling, so we're safe there. Is there any conditional logic that hinges on potentially uninitialized variables? Nope, the code simply calls `virtio_reset_device(vdev)`. Does this patch involve allocating or initializing any complex data structures in a way that could lead to later reads of uninitialized fields? Again, no. And finally, does this affect any bounds checks or introduce a way to access uninitialized bytes? No on that front as well.

The crux of the issue is this: If `virtio_device_ready(vdev)` has been called, the device is considered operational, but if subsequent initialization steps fail, like `blk_revalidate_disk_zones` or `device_add_disk`, and we tear down the disk and free resources without resetting the virtio device, the host could end up accessing freed memory or getting interrupts on stale data. That sounds like a classic use-after-free scenario or invalid memory access which KASAN would detect.

Now, KMSAN focuses on detecting reads of uninitialized memory and information leaks. Given my analysis, this patch doesn't introduce any new uninitialized memory or any leakage. KMSAN isn't the right tool here.

So, I need to double-check this: the rule is, if KASAN, LOCKDEP, or standard bug detectors can catch the issue, KMSAN is overkill. It's expensive to run a dedicated KMSAN session, and it should only be used if we're dealing with risks that KMSAN *specifically* targets: uninitialized memory.

This patch is about ensuring proper cleanup order in an error path, after `virtio_device_ready()`. If the virtio device isn't reset before freeing resources, we could have concurrent access or use-after-free, which KASAN *is* designed to find. This patch doesn't introduce, allocate, or expose any uninitialized stack or heap memory, nor alter branching on uninitialized data or copy any uninitialized data to user space. Therefore, there are no uninitialized memory risks.

Therefore, `NeedsKMSAN` should be false. Time to call the `set-results` tool.

{
  "KMSANReasoning": "The patch inserts a call to virtio_reset_device(vdev) in the error cleanup path (out_cleanup_disk) of virtblk_probe(). When probe fails after virtio_device_ready() was already invoked, resetting the device stops virtqueue operations and hardware interrupts before freeing the tag set, virtqueues, and disk structures.\n\nThis change exclusively addresses device teardown order and avoids potential use-after-free or race conditions where host/device accesses freed structures, which falls squarely within the scope of KASAN. The patch does not touch, allocate, or read any uninitialized memory, does not alter data boundaries or control flow based on uninitialized fields, and does not leak kernel memory to user space. Therefore, a dedicated KMSAN fuzzing session is not warranted.",
  "NeedsKMSAN": false
}

{
  "KMSANReasoning": "The patch inserts a call to virtio_reset_device(vdev) in the error cleanup path (out_cleanup_disk) of virtblk_probe(). When probe fails after virtio_device_ready() was already invoked, resetting the device stops virtqueue operations and hardware interrupts before freeing the tag set, virtqueues, and disk structures.\n\nThis change exclusively addresses device teardown order and avoids potential use-after-free or race conditions where host/device accesses freed structures, which falls squarely within the scope of KASAN. The patch does not touch, allocate, or read any uninitialized memory, does not alter data boundaries or control flow based on uninitialized fields, and does not leak kernel memory to user space. Therefore, a dedicated KMSAN fuzzing session is not warranted.",
  "NeedsKMSAN": false
}

LLM Calls Summary:
Total Calls	Total Tokens	Avg Tokens	Total Duration (Seconds)	Avg Duration (Seconds)

Tool Calls Summary:
Total Calls	Total Duration (Seconds)	Avg Duration (Seconds)