| Seq | Timestamp | Type | Name | Duration |
|---|---|---|---|---|
| 0/0 | 2026/10/18 07:58 | flow | patch-triage |
1mArgs:null Results: {
"EnableConfigs": null,
"FocusSymbols": [],
"KMSANReasoning": "",
"NeedsKMSAN": false,
"Reasoning": "The patch modifies `init_memory_definitions()` and introduces `ivrs_block_type_ivmd()` in `drivers/iommu/amd/init.c`. These functions execute exclusively during early kernel boot (`__init`) while parsing the firmware-provided ACPI IVRS tables. Because this code runs prior to userspace execution and is subsequently freed from memory via `free_initmem()`, it is structurally unreachable by syzkaller runtime fuzzing.",
"WorthFuzzing": false
} |
| 1/1 | 2026/10/18 07:58 | action | read-patch-diff |
0mArgs:null Results: {
"PatchDiff": "commit f9158941d1c0681740bade75a1e03938d94b28e7\nAuthor: syz-cluster \u003ctriage@syzkaller.com\u003e\nDate: Sun Oct 18 07:58:36 2026 +0000\n\n syz-cluster: applied patch under review\n\ndiff --git a/drivers/iommu/amd/init.c b/drivers/iommu/amd/init.c\nindex 8ec8a6fccaaf3..00e1d0be749f7 100644\n--- a/drivers/iommu/amd/init.c\n+++ b/drivers/iommu/amd/init.c\n@@ -2716,6 +2716,15 @@ static int __init init_unity_map_range(struct ivmd_header *m,\n \treturn 0;\n }\n \n+static bool ivrs_block_type_ivmd(u8 type)\n+{\n+\tif (type == ACPI_IVMD_TYPE ||\n+\t type == ACPI_IVMD_TYPE_ALL ||\n+\t type == ACPI_IVMD_TYPE_RANGE)\n+\t\treturn true;\n+\treturn false;\n+}\n+\n /* iterates over all memory definitions we find in the ACPI table */\n static int __init init_memory_definitions(struct acpi_table_header *table)\n {\n@@ -2727,10 +2736,11 @@ static int __init init_memory_definitions(struct acpi_table_header *table)\n \n \twhile (p \u003c end) {\n \t\tm = (struct ivmd_header *)p;\n+\t\tp += m-\u003elength;\n+\t\tif (!ivrs_block_type_ivmd(m-\u003etype))\n+\t\t\tcontinue;\n \t\tif (m-\u003eflags \u0026 (IVMD_FLAG_UNITY_MAP | IVMD_FLAG_EXCL_RANGE))\n \t\t\tinit_unity_map_range(m, table);\n-\n-\t\tp += m-\u003elength;\n \t}\n \n \treturn 0;\n"
} |
| 2/1 | 2026/10/18 07:58 | agent | patch-evaluator |
1mModel:core Args: null Results: {
"EnableConfigs": null,
"FocusSymbols": [],
"Reasoning": "The patch modifies `init_memory_definitions()` and introduces `ivrs_block_type_ivmd()` in `drivers/iommu/amd/init.c`. These functions execute exclusively during early kernel boot (`__init`) while parsing the firmware-provided ACPI IVRS tables. Because this code runs prior to userspace execution and is subsequently freed from memory via `free_initmem()`, it is structurally unreachable by syzkaller runtime fuzzing.",
"WorthFuzzing": false
}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 f9158941d1c0681740bade75a1e03938d94b28e7
Author: syz-cluster <triage@syzkaller.com>
Date: Sun Oct 18 07:58:36 2026 +0000
syz-cluster: applied patch under review
diff --git a/drivers/iommu/amd/init.c b/drivers/iommu/amd/init.c
index 8ec8a6fccaaf3..00e1d0be749f7 100644
--- a/drivers/iommu/amd/init.c
+++ b/drivers/iommu/amd/init.c
@@ -2716,6 +2716,15 @@ static int __init init_unity_map_range(struct ivmd_header *m,
return 0;
}
+static bool ivrs_block_type_ivmd(u8 type)
+{
+ if (type == ACPI_IVMD_TYPE ||
+ type == ACPI_IVMD_TYPE_ALL ||
+ type == ACPI_IVMD_TYPE_RANGE)
+ return true;
+ return false;
+}
+
/* iterates over all memory definitions we find in the ACPI table */
static int __init init_memory_definitions(struct acpi_table_header *table)
{
@@ -2727,10 +2736,11 @@ static int __init init_memory_definitions(struct acpi_table_header *table)
while (p < end) {
m = (struct ivmd_header *)p;
+ p += m->length;
+ if (!ivrs_block_type_ivmd(m->type))
+ continue;
if (m->flags & (IVMD_FLAG_UNITY_MAP | IVMD_FLAG_EXCL_RANGE))
init_unity_map_range(m, table);
-
- p += m->length;
}
return 0;
|
| 3/2 | 2026/10/18 07:58 | llm | patch-evaluator |
0mModel:gemini-3.8-flash Args: null Results: null Tokens: input: 3230 output: 40 thoughts: 503 Thoughts: **Patch Evaluation: AMD IOMMU Initialization** Okay, so I've got this patch to review, targeting the amd64 architecture. My initial assessment starts with the code diff itself, specifically looking at `drivers/iommu/amd/init.c`. The core of the change seems to introduce a new function, `ivrs_block_type_ivmd()`. Looking at the diff, it looks like this function evaluates whether a given `u8 type` matches certain ACPI IVMD types, which are `ACPI_IVMD_TYPE`, `ACPI_IVMD_TYPE_ALL`, or `ACPI_IVMD_TYPE_RANGE`. If it matches any of these, it returns `true`; otherwise, it returns `false`. The crucial part here is how this new function is *used*. I see that it's inserted into the `init_memory_definitions` function, right before the block that processes IVMD headers. Specifically, it seems to add a check using this new function to determine whether to process an IVMD block. In other words, it is a filtering mechanism for valid IVMD blocks. My initial thought is that this introduces a new conditional statement. Before, all IVMD blocks were processed, but now, a block is skipped if it does not pass the test. I'm now going to investigate how that new conditional statement affects the rest of the logic, using the tool to read the file or grep to check any dependencies on the blocks the function filters. |
| 4/2 | 2026/10/18 07:58 | tool | read-file |
0mArgs:{
"File": "drivers/iommu/amd/init.c",
"FirstLine": 2710,
"LineCount": 60
}Results: {
"Contents": "2710:\t\t\t PCI_BUS_NUM(e-\u003edevid_end),\n2711:\t\t\t PCI_SLOT(e-\u003edevid_end), PCI_FUNC(e-\u003edevid_end),\n2712:\t\t\t e-\u003eaddress_start, e-\u003eaddress_end, m-\u003eflags);\n2713:\t\n2714:\t\tlist_add_tail(\u0026e-\u003elist, \u0026pci_seg-\u003eunity_map);\n2715:\t\n2716:\t\treturn 0;\n2717:\t}\n2718:\t\n2719:\tstatic bool ivrs_block_type_ivmd(u8 type)\n2720:\t{\n2721:\t\tif (type == ACPI_IVMD_TYPE ||\n2722:\t\t type == ACPI_IVMD_TYPE_ALL ||\n2723:\t\t type == ACPI_IVMD_TYPE_RANGE)\n2724:\t\t\treturn true;\n2725:\t\treturn false;\n2726:\t}\n2727:\t\n2728:\t/* iterates over all memory definitions we find in the ACPI table */\n2729:\tstatic int __init init_memory_definitions(struct acpi_table_header *table)\n2730:\t{\n2731:\t\tu8 *p = (u8 *)table, *end = (u8 *)table;\n2732:\t\tstruct ivmd_header *m;\n2733:\t\n2734:\t\tend += table-\u003elength;\n2735:\t\tp += IVRS_HEADER_LENGTH;\n2736:\t\n2737:\t\twhile (p \u003c end) {\n2738:\t\t\tm = (struct ivmd_header *)p;\n2739:\t\t\tp += m-\u003elength;\n2740:\t\t\tif (!ivrs_block_type_ivmd(m-\u003etype))\n2741:\t\t\t\tcontinue;\n2742:\t\t\tif (m-\u003eflags \u0026 (IVMD_FLAG_UNITY_MAP | IVMD_FLAG_EXCL_RANGE))\n2743:\t\t\t\tinit_unity_map_range(m, table);\n2744:\t\t}\n2745:\t\n2746:\t\treturn 0;\n2747:\t}\n2748:\t\n2749:\t/*\n2750:\t * Init the device table to not allow DMA access for devices\n2751:\t */\n2752:\tstatic void init_device_table_dma(struct amd_iommu_pci_seg *pci_seg)\n2753:\t{\n2754:\t\tu32 devid;\n2755:\t\tstruct dev_table_entry *dev_table = pci_seg-\u003edev_table;\n2756:\t\n2757:\t\tif (!dev_table || amd_iommu_pgtable == PD_MODE_NONE)\n2758:\t\t\treturn;\n2759:\t\n2760:\t\tfor (devid = 0; devid \u003c= pci_seg-\u003elast_bdf; ++devid) {\n2761:\t\t\tset_dte_bit(\u0026dev_table[devid], DEV_ENTRY_VALID);\n2762:\t\t\tif (!amd_iommu_snp_en)\n2763:\t\t\t\tset_dte_bit(\u0026dev_table[devid], DEV_ENTRY_TRANSLATION);\n2764:\t\t}\n2765:\t}\n2766:\t\n2767:\tstatic void __init uninit_device_table_dma(struct amd_iommu_pci_seg *pci_seg)\n2768:\t{\n2769:\t\tu32 devid;\n"
} |
| 5/2 | 2026/10/18 07:58 | llm | patch-evaluator |
0mModel:gemini-3.8-flash Args: null Results: null Tokens: input: 5040 output: 34 thoughts: 15 Thoughts: Here's my take on those thoughts: **Tracing the Call Path: `init_memory_definitions`** Alright, let's dive in. My immediate thought is, "Where exactly does this `init_memory_definitions` function get called?" I need to understand its context. Knowing the call sites is absolutely crucial to grasping its purpose and potential impact within the larger system. I'm going to start by tracing its usage. Understanding its dependencies will allow me to reason about any potential bugs and evaluate its efficiency. Time to go hunting for those call references. Let's see what we can find. |
| 6/2 | 2026/10/18 07:58 | tool | grepper |
0mArgs:{
"Expression": "init_memory_definitions",
"PathPrefixes": [
"drivers/iommu/amd/"
]
}Results: {
"Output": "drivers/iommu/amd/init.c=2719=static bool ivrs_block_type_ivmd(u8 type)\n--\ndrivers/iommu/amd/init.c-2728-/* iterates over all memory definitions we find in the ACPI table */\ndrivers/iommu/amd/init.c:2729:static int __init init_memory_definitions(struct acpi_table_header *table)\ndrivers/iommu/amd/init.c-2730-{\n--\ndrivers/iommu/amd/init.c=3286=static int __init early_amd_iommu_init(void)\n--\ndrivers/iommu/amd/init.c-3385-\ndrivers/iommu/amd/init.c:3386:\tret = init_memory_definitions(ivrs_base);\ndrivers/iommu/amd/init.c-3387-\tif (ret)\n"
} |
| 7/2 | 2026/10/18 07:58 | llm | patch-evaluator |
0mModel:gemini-3.8-flash Args: null Results: null Tokens: input: 5463 output: 23 thoughts: 23 Thoughts: Okay, here's my attempt at summarizing that thought process, keeping in mind the expert user and using the first-person perspective: **Investigating `early_amd_iommu_init`** Alright, let's dive into this `early_amd_iommu_init` function. My initial thought is to understand its purpose and, crucially, where it's being invoked within the system. Is it part of the early boot process, some kind of initialization stage for AMD IOMMUs? Knowing the call chain is going to be key here. I need to trace its origins, understand the context in which it's executed, and see what dependencies it has. What's the triggering mechanism? What other IOMMU related routines are close by? It's all about context and how this function fits into the larger IOMMU initialization puzzle. |
| 8/2 | 2026/10/18 07:58 | tool | grepper |
0mArgs:{
"Expression": "early_amd_iommu_init"
}Results: {
"Output": "drivers/iommu/amd/init.c=3254=static void __init ivinfo_init(void *ivrs)\n--\ndrivers/iommu/amd/init.c-3285- */\ndrivers/iommu/amd/init.c:3286:static int __init early_amd_iommu_init(void)\ndrivers/iommu/amd/init.c-3287-{\n--\ndrivers/iommu/amd/init.c=3540=static int __init state_next(void)\n--\ndrivers/iommu/amd/init.c-3559-\tcase IOMMU_IVRS_DETECTED:\ndrivers/iommu/amd/init.c:3560:\t\tret = early_amd_iommu_init();\ndrivers/iommu/amd/init.c-3561-\t\tinit_state = ret ? IOMMU_INIT_ERROR : IOMMU_ACPI_FINISHED;\n"
} |
| 9/2 | 2026/10/18 07:58 | llm | patch-evaluator |
0mModel:gemini-3.8-flash Args: null Results: null Tokens: input: 5943 output: 40 thoughts: 22 Thoughts: Okay, let's dive into this. Here's how I'd approach this task, as if these were my internal thoughts: **Analyzing AMD IOMMU Driver Initialization** Alright, I need to understand what's going on with `state_next` and the AMD IOMMU driver initialization. Specifically, I need to figure out the interplay between the two. Where does this `state_next` variable come into play? Is it a crucial part of the initialization sequence, or something that happens afterward? I need to understand the control flow, the data structures, and the dependencies. My intuition is that `state_next` likely represents a stage or state the IOMMU driver is going through during its initialization process. Perhaps it dictates which functions are called or which checks are performed. I need to trace its usage, identify its definitions, and ultimately determine its purpose in the overall context of the AMD IOMMU driver's start up. |
| 10/2 | 2026/10/18 07:58 | tool | read-file |
0mArgs:{
"File": "drivers/iommu/amd/init.c",
"FirstLine": 3540,
"LineCount": 80
}Results: {
"Contents": "3540:\tstatic int __init state_next(void)\n3541:\t{\n3542:\t\tint ret = 0;\n3543:\t\n3544:\t\tswitch (init_state) {\n3545:\t\tcase IOMMU_START_STATE:\n3546:\t\t\tif (no_iommu || amd_iommu_disabled) {\n3547:\t\t\t\tinit_state\t= IOMMU_CMDLINE_DISABLED;\n3548:\t\t\t\tret\t\t= -EINVAL;\n3549:\t\t\t} else if (!amd_iommu_sme_check()) {\n3550:\t\t\t\tinit_state\t= IOMMU_INIT_ERROR;\n3551:\t\t\t\tret\t\t= -EINVAL;\n3552:\t\t\t} else if (!detect_ivrs()) {\n3553:\t\t\t\tinit_state\t= IOMMU_NOT_FOUND;\n3554:\t\t\t\tret\t\t= -ENODEV;\n3555:\t\t\t} else {\n3556:\t\t\t\tinit_state\t= IOMMU_IVRS_DETECTED;\n3557:\t\t\t}\n3558:\t\t\tbreak;\n3559:\t\tcase IOMMU_IVRS_DETECTED:\n3560:\t\t\tret = early_amd_iommu_init();\n3561:\t\t\tinit_state = ret ? IOMMU_INIT_ERROR : IOMMU_ACPI_FINISHED;\n3562:\t\t\tbreak;\n3563:\t\tcase IOMMU_ACPI_FINISHED:\n3564:\t\t\tearly_enable_iommus();\n3565:\t\t\tx86_platform.iommu_shutdown = disable_iommus;\n3566:\t\t\tinit_state = IOMMU_ENABLED;\n3567:\t\t\tbreak;\n3568:\t\tcase IOMMU_ENABLED:\n3569:\t\t\tregister_syscore(\u0026amd_iommu_syscore);\n3570:\t\t\tiommu_snp_enable();\n3571:\t\n3572:\t\t\tamd_iommu_apply_erratum_snp();\n3573:\t\n3574:\t\t\t/* Allocate/enable event log buffer */\n3575:\t\t\tif (is_kdump_kernel())\n3576:\t\t\t\tret = remap_event_buffer();\n3577:\t\t\telse\n3578:\t\t\t\tret = alloc_event_buffer();\n3579:\t\n3580:\t\t\tif (ret) {\n3581:\t\t\t\tinit_state = IOMMU_INIT_ERROR;\n3582:\t\t\t\tbreak;\n3583:\t\t\t}\n3584:\t\t\tiommu_enable_event_buffer();\n3585:\t\n3586:\t\t\tret = amd_iommu_init_pci();\n3587:\t\t\tinit_state = ret ? IOMMU_INIT_ERROR : IOMMU_PCI_INIT;\n3588:\t\t\tbreak;\n3589:\t\tcase IOMMU_PCI_INIT:\n3590:\t\t\tret = amd_iommu_enable_interrupts();\n3591:\t\t\tinit_state = ret ? IOMMU_INIT_ERROR : IOMMU_INTERRUPTS_EN;\n3592:\t\t\tbreak;\n3593:\t\tcase IOMMU_INTERRUPTS_EN:\n3594:\t\t\tinit_state = IOMMU_INITIALIZED;\n3595:\t\t\tbreak;\n3596:\t\tcase IOMMU_INITIALIZED:\n3597:\t\t\t/* Nothing to do */\n3598:\t\t\tbreak;\n3599:\t\tcase IOMMU_NOT_FOUND:\n3600:\t\tcase IOMMU_INIT_ERROR:\n3601:\t\tcase IOMMU_CMDLINE_DISABLED:\n3602:\t\t\t/* Error states =\u003e do nothing */\n3603:\t\t\tret = -EINVAL;\n3604:\t\t\tbreak;\n3605:\t\tdefault:\n3606:\t\t\t/* Unknown state */\n3607:\t\t\tBUG();\n3608:\t\t}\n3609:\t\n3610:\t\tif (ret) {\n3611:\t\t\tfree_dma_resources();\n3612:\t\t\tif (!irq_remapping_enabled) {\n3613:\t\t\t\tdisable_iommus();\n3614:\t\t\t\tfree_iommu_resources();\n3615:\t\t\t} else {\n3616:\t\t\t\tstruct amd_iommu *iommu;\n3617:\t\t\t\tstruct amd_iommu_pci_seg *pci_seg;\n3618:\t\n3619:\t\t\t\tfor_each_pci_segment(pci_seg)\n"
} |
| 11/2 | 2026/10/18 07:58 | llm | patch-evaluator |
0mModel:gemini-3.8-flash Args: null Results: null Tokens: input: 7395 output: 35 thoughts: 13 Thoughts: Okay, here's my attempt at summarizing that thought process, tailored for an expert audience: **Analyzing `state_next` Calls** Alright, let's get down to brass tacks. I need to understand how this `state_next` function is being utilized. My first instinct is to trace its calls. Where is this thing actually *being* invoked? Knowing the call sites will immediately give me critical context on its purpose, the data it's operating on, and the overall control flow it's a part of. This is ground zero for understanding its behavior and impact. I need to quickly identify the points of entry. From there, I can reverse-engineer the overall architecture. |
| 12/2 | 2026/10/18 07:58 | tool | grepper |
0mArgs:{
"Expression": "state_next",
"PathPrefixes": [
"drivers/iommu/amd/init.c"
]
}Results: {
"Output": "drivers/iommu/amd/init.c=2174=static int __init iommu_init_pci(struct amd_iommu *iommu)\n--\ndrivers/iommu/amd/init.c-2283-\t\t * IOMMU. Do not return an error to enable IRQ remapping\ndrivers/iommu/amd/init.c:2284:\t\t * in state_next(), DTE[V, TV] must eventually be set to 0.\ndrivers/iommu/amd/init.c-2285-\t\t */\n--\ndrivers/iommu/amd/init.c=3532=static bool amd_iommu_sme_check(void);\n--\ndrivers/iommu/amd/init.c-3539-\ndrivers/iommu/amd/init.c:3540:static int __init state_next(void)\ndrivers/iommu/amd/init.c-3541-{\n--\ndrivers/iommu/amd/init.c=3629=static int __init iommu_go_to_state(enum iommu_init_state state)\n--\ndrivers/iommu/amd/init.c-3650-\t\t\tbreak;\ndrivers/iommu/amd/init.c:3651:\t\tret = state_next();\ndrivers/iommu/amd/init.c-3652-\t}\n"
} |
| 13/2 | 2026/10/18 07:58 | llm | patch-evaluator |
0mModel:gemini-3.8-flash Args: null Results: null Tokens: input: 7952 output: 38 thoughts: 19 Thoughts: Okay, here's my summary, tailored for an expert audience, as if it were my thought process: **Diving into `iommu_go_to_state` Call Sites** Right, time to get my bearings. The task at hand is to understand the behavior of `iommu_go_to_state`, and the best way to do that is to trace its usage. I need to figure out the context in which this function is invoked. So, my initial thought is, "Let's track down all the call sites." I'll need to use my usual tools to perform a thorough code search. I expect there'll be quite a few, given the nature of IOMMU state management. I'll be looking for clues in the calling functions about what is happening *before* and *after* the state transition. This will give me a better understanding of the overall purpose and workflow. I'll be interested in what parameters are passed to it as well. |
| 14/2 | 2026/10/18 07:58 | tool | grepper |
0mArgs:{
"Expression": "iommu_go_to_state",
"PathPrefixes": [
"drivers/iommu/amd/"
]
}Results: {
"Output": "drivers/iommu/amd/init.c=3540=static int __init state_next(void)\n--\ndrivers/iommu/amd/init.c-3628-\ndrivers/iommu/amd/init.c:3629:static int __init iommu_go_to_state(enum iommu_init_state state)\ndrivers/iommu/amd/init.c-3630-{\n--\ndrivers/iommu/amd/init.c=3672=int __init amd_iommu_prepare(void)\n--\ndrivers/iommu/amd/init.c-3677-\ndrivers/iommu/amd/init.c:3678:\tret = iommu_go_to_state(IOMMU_ACPI_FINISHED);\ndrivers/iommu/amd/init.c-3679-\tif (ret) {\n--\ndrivers/iommu/amd/init.c=3687=int __init amd_iommu_enable(void)\n--\ndrivers/iommu/amd/init.c-3690-\ndrivers/iommu/amd/init.c:3691:\tret = iommu_go_to_state(IOMMU_ENABLED);\ndrivers/iommu/amd/init.c-3692-\tif (ret)\n--\ndrivers/iommu/amd/init.c=3723=static int __init amd_iommu_init(void)\n--\ndrivers/iommu/amd/init.c-3726-\ndrivers/iommu/amd/init.c:3727:\tret = iommu_go_to_state(IOMMU_INITIALIZED);\ndrivers/iommu/amd/init.c-3728-#ifdef CONFIG_GART_IOMMU\n--\ndrivers/iommu/amd/init.c=3770=void __init amd_iommu_detect(void)\n--\ndrivers/iommu/amd/init.c-3773-\ndrivers/iommu/amd/init.c:3774:\tret = iommu_go_to_state(IOMMU_IVRS_DETECTED);\ndrivers/iommu/amd/init.c-3775-\tif (ret)\n"
} |
| 15/2 | 2026/10/18 07:58 | llm | patch-evaluator |
0mModel:gemini-3.8-flash Args: null Results: null Tokens: input: 8803 output: 26 thoughts: 331 Thoughts: **My Assessment of the `init_memory_definitions` Function** Okay, so I see that `init_memory_definitions` is flagged with `__init`. Right off the bat, that tells me this is code that's intended to run *very* early, during kernel boot. It's parsing the ACPI IVRS table, the I/O Virtualization Reporting Structure, which the BIOS/firmware provides. My initial thought is: is this even relevant to fuzzing? Could syzkaller *possibly* trigger this code path at runtime? It seems highly unlikely. I need to investigate if there's any way this can be reached *after* the initial boot sequence in standard fuzzing environments like QEMU or GCE. I should also quickly confirm what `init_memory_definitions` actually *does*. It's parsing the `ivrs_base`, which confirms it's handling the ACPI IVRS table. Okay, so it *is* IVRS ACPI table parsing, but it is executed only during kernel boot. A quick look down the call chain confirms this: `amd_iommu_detect`, `amd_iommu_prepare`, `amd_iommu_init`, `init_memory_definitions`, `init_unity_map_range`, and `early_amd_iommu_init` – they're all marked `__init`. That's a strong indicator that this specific path is off-limits for later fuzzing. However, I'm not going to write this off completely. What about ACPI table overrides or configfs ACPI table loading? Does the loading of *alternative* ACPI tables via configfs (or other mechanisms) also involve parsing the IVRS? That's the key question I need to answer. I need to dig into the ACPI table loading mechanisms via configfs to see if it triggers an IVRS parse. |
| 16/2 | 2026/10/18 07:59 | tool | grepper |
0mArgs:{
"Expression": "acpi_table_init|configfs.*acpi"
}Results: {
"Output": "MAINTAINERS=285=T:\tgit git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm\nMAINTAINERS:286:F:\tDocumentation/ABI/testing/configfs-acpi\nMAINTAINERS-287-F:\tDocumentation/ABI/testing/sysfs-bus-acpi\n--\narch/arm64/kernel/acpi.c=198=void __init acpi_boot_table_init(void)\n--\narch/arm64/kernel/acpi.c-223-\t */\narch/arm64/kernel/acpi.c:224:\tif (acpi_table_init() || acpi_fadt_sanity_check()) {\narch/arm64/kernel/acpi.c-225-\t\tpr_err(\"Failed to init ACPI tables\\n\");\n--\narch/loongarch/kernel/acpi.c=264=void __init acpi_boot_table_init(void)\n--\narch/loongarch/kernel/acpi.c-274-\t */\narch/loongarch/kernel/acpi.c:275:\tif (acpi_table_init()) {\narch/loongarch/kernel/acpi.c-276-\t\tdisable_acpi();\n--\narch/riscv/kernel/acpi.c=126=void __init acpi_boot_table_init(void)\n--\narch/riscv/kernel/acpi.c-151-\t */\narch/riscv/kernel/acpi.c:152:\tif (acpi_table_init() || acpi_fadt_sanity_check()) {\narch/riscv/kernel/acpi.c-153-\t\tpr_err(\"Failed to init ACPI tables\\n\");\n--\narch/x86/kernel/acpi/boot.c=1516=static const struct dmi_system_id acpi_dmi_table_late[] __initconst = {\n--\narch/x86/kernel/acpi/boot.c-1576- *\narch/x86/kernel/acpi/boot.c:1577: * acpi_table_init() is separate to allow reading SRAT without\narch/x86/kernel/acpi/boot.c-1578- * other side effects.\n--\narch/x86/kernel/acpi/boot.c=1608=int __init early_acpi_boot_init(void)\n--\narch/x86/kernel/acpi/boot.c-1612-\narch/x86/kernel/acpi/boot.c:1613:\tacpi_table_init_complete();\narch/x86/kernel/acpi/boot.c-1614-\n--\ndrivers/acpi/acpi_configfs.c=92=CONFIGFS_BIN_ATTR(acpi_table_, aml, NULL, MAX_ACPI_TABLE_SIZE);\ndrivers/acpi/acpi_configfs.c-93-\ndrivers/acpi/acpi_configfs.c:94:static struct configfs_bin_attribute *acpi_table_bin_attrs[] = {\ndrivers/acpi/acpi_configfs.c-95-\t\u0026acpi_table_attr_aml,\n--\ndrivers/acpi/acpi_configfs.c=188=CONFIGFS_ATTR_RO(acpi_table_, asl_compiler_revision);\ndrivers/acpi/acpi_configfs.c-189-\ndrivers/acpi/acpi_configfs.c:190:static struct configfs_attribute *acpi_table_attrs[] = {\ndrivers/acpi/acpi_configfs.c-191-\t\u0026acpi_table_attr_signature,\n--\ndrivers/acpi/acpi_configfs.c=221=static void acpi_table_drop_item(struct config_group *group,\n--\ndrivers/acpi/acpi_configfs.c-230-\ndrivers/acpi/acpi_configfs.c:231:static struct configfs_group_operations acpi_table_group_ops = {\ndrivers/acpi/acpi_configfs.c-232-\t.make_item = acpi_table_make_item,\n--\ndrivers/acpi/acpi_configfs.c=241=static const struct config_item_type acpi_root_group_type = {\n--\ndrivers/acpi/acpi_configfs.c-244-\ndrivers/acpi/acpi_configfs.c:245:static struct configfs_subsystem acpi_configfs = {\ndrivers/acpi/acpi_configfs.c-246-\t.su_group = {\n--\ndrivers/acpi/acpi_configfs.c=255=static int __init acpi_configfs_init(void)\n--\ndrivers/acpi/acpi_configfs.c-261-\ndrivers/acpi/acpi_configfs.c:262:\tret = configfs_register_subsystem(\u0026acpi_configfs);\ndrivers/acpi/acpi_configfs.c-263-\tif (ret)\n--\ndrivers/acpi/acpi_configfs.c-268-\tif (IS_ERR(acpi_table_group)) {\ndrivers/acpi/acpi_configfs.c:269:\t\tconfigfs_unregister_subsystem(\u0026acpi_configfs);\ndrivers/acpi/acpi_configfs.c-270-\t\treturn PTR_ERR(acpi_table_group);\n--\ndrivers/acpi/acpi_configfs.c=277=static void __exit acpi_configfs_exit(void)\ndrivers/acpi/acpi_configfs.c-278-{\ndrivers/acpi/acpi_configfs.c:279:\tconfigfs_unregister_default_group(acpi_table_group);\ndrivers/acpi/acpi_configfs.c:280:\tconfigfs_unregister_subsystem(\u0026acpi_configfs);\ndrivers/acpi/acpi_configfs.c-281-}\n--\ndrivers/acpi/tables.c=546=static acpi_status\ndrivers/acpi/tables.c:547:acpi_table_initrd_override(struct acpi_table_header *existing_table,\ndrivers/acpi/tables.c-548-\t\t\t acpi_physical_address *address, u32 *length)\n--\ndrivers/acpi/tables.c-581-\t\t * Mark the table to avoid being used in\ndrivers/acpi/tables.c:582:\t\t * acpi_table_initrd_scan() and check the revision.\ndrivers/acpi/tables.c-583-\t\t */\n--\ndrivers/acpi/tables.c-604-\ndrivers/acpi/tables.c:605:static void __init acpi_table_initrd_scan(void)\ndrivers/acpi/tables.c-606-{\n--\ndrivers/acpi/tables.c-633-\t\t * Mark the table to avoid being used in\ndrivers/acpi/tables.c:634:\t\t * acpi_table_initrd_override(). Though this is not possible\ndrivers/acpi/tables.c-635-\t\t * because override is disabled in acpi_install_physical_table().\n--\ndrivers/acpi/tables.c=653=static acpi_status\ndrivers/acpi/tables.c:654:acpi_table_initrd_override(struct acpi_table_header *existing_table,\ndrivers/acpi/tables.c-655-\t\t\t acpi_physical_address *address,\n--\ndrivers/acpi/tables.c-662-\ndrivers/acpi/tables.c:663:static void __init acpi_table_initrd_scan(void)\ndrivers/acpi/tables.c-664-{\n--\ndrivers/acpi/tables.c=669=acpi_os_physical_table_override(struct acpi_table_header *existing_table,\n--\ndrivers/acpi/tables.c-672-{\ndrivers/acpi/tables.c:673:\treturn acpi_table_initrd_override(existing_table, address,\ndrivers/acpi/tables.c-674-\t\t\t\t\t table_length);\n--\ndrivers/acpi/tables.c=733=void __init acpi_reserve_initial_tables(void)\n--\ndrivers/acpi/tables.c-751-\ndrivers/acpi/tables.c:752:void __init acpi_table_init_complete(void)\ndrivers/acpi/tables.c-753-{\ndrivers/acpi/tables.c:754:\tacpi_table_initrd_scan();\ndrivers/acpi/tables.c-755-\tcheck_multiple_madt();\n--\ndrivers/acpi/tables.c-757-\ndrivers/acpi/tables.c:758:int __init acpi_table_init(void)\ndrivers/acpi/tables.c-759-{\n--\ndrivers/acpi/tables.c-765-\ndrivers/acpi/tables.c:766:\tacpi_table_init_complete();\ndrivers/acpi/tables.c-767-\n--\ninclude/linux/acpi.h=228=void acpi_reserve_initial_tables (void);\ninclude/linux/acpi.h:229:void acpi_table_init_complete (void);\ninclude/linux/acpi.h:230:int acpi_table_init (void);\ninclude/linux/acpi.h-231-\n"
} |
| 17/2 | 2026/10/18 07:59 | llm | patch-evaluator |
0mModel:gemini-3.8-flash Args: null Results: null Tokens: input: 12002 output: 38 thoughts: 21 Thoughts: Here's my take on those thoughts, tailored for an expert audience: **Diving into `acpi_configfs.c`** Okay, so I need to understand the permissible ACPI table loading mechanisms implemented within the `acpi_configfs.c` module. Let me go directly into the code and explore what the driver exposes through configfs. I'm especially interested in the specific ACPI tables it allows, since that dictates the flexibility and security posture of the ACPI loading strategy. I'll be looking for clues about the allowed table types, their validation, and any restrictions in place. This will give me the information I need. |
| 18/2 | 2026/10/18 07:59 | tool | read-file |
0mArgs:{
"File": "drivers/acpi/acpi_configfs.c",
"FirstLine": 1,
"LineCount": 60
}Results: {
"Contents": " 1:\t// SPDX-License-Identifier: GPL-2.0-only\n 2:\t/*\n 3:\t * ACPI configfs support\n 4:\t *\n 5:\t * Copyright (c) 2016 Intel Corporation\n 6:\t */\n 7:\t\n 8:\t#define pr_fmt(fmt) \"ACPI configfs: \" fmt\n 9:\t\n 10:\t#include \u003clinux/init.h\u003e\n 11:\t#include \u003clinux/module.h\u003e\n 12:\t#include \u003clinux/configfs.h\u003e\n 13:\t#include \u003clinux/acpi.h\u003e\n 14:\t#include \u003clinux/security.h\u003e\n 15:\t\n 16:\tstatic struct config_group *acpi_table_group;\n 17:\t\n 18:\tstruct acpi_table {\n 19:\t\tstruct config_item cfg;\n 20:\t\tstruct acpi_table_header *header;\n 21:\t\tu32 index;\n 22:\t};\n 23:\t\n 24:\tstatic ssize_t acpi_table_aml_write(struct config_item *cfg,\n 25:\t\t\t\t\t const void *data, size_t size)\n 26:\t{\n 27:\t\tconst struct acpi_table_header *header = data;\n 28:\t\tstruct acpi_table *table;\n 29:\t\tint ret = security_locked_down(LOCKDOWN_ACPI_TABLES);\n 30:\t\n 31:\t\tif (ret)\n 32:\t\t\treturn ret;\n 33:\t\n 34:\t\ttable = container_of(cfg, struct acpi_table, cfg);\n 35:\t\n 36:\t\tif (table-\u003eheader) {\n 37:\t\t\tpr_err(\"table already loaded\\n\");\n 38:\t\t\treturn -EBUSY;\n 39:\t\t}\n 40:\t\n 41:\t\tif (header-\u003elength != size) {\n 42:\t\t\tpr_err(\"invalid table length\\n\");\n 43:\t\t\treturn -EINVAL;\n 44:\t\t}\n 45:\t\n 46:\t\tif (memcmp(header-\u003esignature, ACPI_SIG_SSDT, 4)) {\n 47:\t\t\tpr_err(\"invalid table signature\\n\");\n 48:\t\t\treturn -EINVAL;\n 49:\t\t}\n 50:\t\n 51:\t\ttable = container_of(cfg, struct acpi_table, cfg);\n 52:\t\n 53:\t\ttable-\u003eheader = kmemdup(header, header-\u003elength, GFP_KERNEL);\n 54:\t\tif (!table-\u003eheader)\n 55:\t\t\treturn -ENOMEM;\n 56:\t\n 57:\t\tret = acpi_load_table(table-\u003eheader, \u0026table-\u003eindex);\n 58:\t\tif (ret) {\n 59:\t\t\tkfree(table-\u003eheader);\n 60:\t\t\ttable-\u003eheader = NULL;\n"
} |
| 19/2 | 2026/10/18 07:59 | llm | patch-evaluator |
0mModel:gemini-3.8-flash Args: null Results: null Tokens: input: 12963 output: 58 thoughts: 209 Thoughts: **Analyzing ACPI Table Loading and AMD IOMMU Initialization** Okay, so `acpi_table_aml_write` is very specific. I see that it explicitly checks for the `ACPI_SIG_SSDT` signature. The check here (`if (memcmp(header->signature, ACPI_SIG_SSDT, 4)) return -EINVAL;`) confirms that configfs is *only* loading SSDTs. That's a good starting point. This limits the scope of what I need to consider with regard to what ACPI tables are supported. Now, let's look at `init_memory_definitions`. The code shows this function is `static int __init init_memory_definitions(struct acpi_table_header *table)`. And it appears to be called exclusively by `early_amd_iommu_init(void)`: specifically via `ret = init_memory_definitions(ivrs_base);`. I see that `early_amd_iommu_init` is invoked during `state_next()`, during early boot, which is an interesting detail. The relationship between `init_memory_definitions` and `early_amd_iommu_init` is direct, so they are likely related, at least in AMD IOMMU initialization. But wait a minute! Let me zoom out. I need to get the bigger picture, the complete initialization sequence for the AMD IOMMU. I need to check how the AMD IOMMU itself is initialized at a higher level within the kernel. I'll search for all calls to key AMD IOMMU functions: `amd_iommu_detect`, `amd_iommu_prepare`, `amd_iommu_enable`, and `amd_iommu_init`. This should give me a complete picture of the entire initialization sequence to understand the context and implications of `early_amd_iommu_init` and its interactions with ACPI tables. |
| 20/2 | 2026/10/18 07:59 | tool | grepper |
0mArgs:{
"Expression": "amd_iommu_detect|amd_iommu_prepare|amd_iommu_enable|amd_iommu_init",
"PathPrefixes": [
"arch/x86/"
]
}Results: {
"Output": "arch/x86/kernel/pci-dma.c=96=void __init pci_iommu_alloc(void)\n--\narch/x86/kernel/pci-dma.c-103-\tgart_iommu_hole_init();\narch/x86/kernel/pci-dma.c:104:\tamd_iommu_detect();\narch/x86/kernel/pci-dma.c-105-\tdetect_intel_iommu();\n"
} |
| 21/2 | 2026/10/18 07:59 | llm | patch-evaluator |
0mModel:gemini-3.8-flash Args: null Results: null Tokens: input: 13787 output: 29 thoughts: 25 Thoughts: Okay, here's my take on those functions. I'll approach this as if I'm thinking through it myself, given my expertise: **Diving into AMD IOMMU Preparation and Enabling** Alright, let's get down to brass tacks. I need to understand the control flow surrounding `amd_iommu_prepare` and `amd_iommu_enable`. From a high-level perspective, they're critical for getting an AMD IOMMU, and by extension, hardware virtualization and device assignment, up and running. I need to know where these hooks are in the boot process. What are the dependencies? Is `amd_iommu_prepare` called early during initialization to set up some basic structures and check for compatibility, and is `amd_iommu_enable` then responsible for the actual hardware initialization and enabling the MMU? Are there any preconditions I should be aware of? Are we talking about basic register programming here, or are there more sophisticated memory mapping configurations happening? I need to understand the order of operations: platform setup first, then IOMMU, or are they interleaved? Any potential race conditions? What are the implications of different BIOS/UEFI settings? I know there are architectural differences across the various generations of AMD CPUs, so I need to check what version is being handled. I need to check for the handling of interrupt remapping. Are these functions responsible for setting up the necessary interrupt translation tables, or is that handled elsewhere? Let's trace through the code and see exactly where these calls are made and with what arguments. I need to look for any error handling to see how these functions respond to various problems during the initialization process. Good, let's start digging. |
| 22/2 | 2026/10/18 07:59 | tool | grepper |
0mArgs:{
"Expression": "amd_iommu_prepare|amd_iommu_enable"
}Results: {
"Output": "drivers/gpu/drm/amd/amdgpu/amdgpu_device.c=3788=int amdgpu_device_init(struct amdgpu_device *adev,\n--\ndrivers/gpu/drm/amd/amdgpu/amdgpu_device.c-3985-\tif (amdgpu_device_use_perfopt(adev)) {\ndrivers/gpu/drm/amd/amdgpu/amdgpu_device.c:3986:\t\tint perfopt_ret = amd_iommu_enable_perfopt(pdev);\ndrivers/gpu/drm/amd/amdgpu/amdgpu_device.c-3987-\n--\ndrivers/gpu/drm/amd/amdgpu/amdgpu_device.c=4710=int amdgpu_device_resume(struct drm_device *dev, bool notify_clients)\n--\ndrivers/gpu/drm/amd/amdgpu/amdgpu_device.c-4730-\tif (amdgpu_device_use_perfopt(adev)) {\ndrivers/gpu/drm/amd/amdgpu/amdgpu_device.c:4731:\t\tint perfopt_ret = amd_iommu_enable_perfopt(adev-\u003epdev);\ndrivers/gpu/drm/amd/amdgpu/amdgpu_device.c-4732-\n--\ndrivers/iommu/amd/amd_iommu.h=35=static inline void amd_iommu_debugfs_setup(void) {}\n--\ndrivers/iommu/amd/amd_iommu.h-38-/* Needed for interrupt remapping */\ndrivers/iommu/amd/amd_iommu.h:39:int amd_iommu_prepare(void);\ndrivers/iommu/amd/amd_iommu.h:40:int amd_iommu_enable(void);\ndrivers/iommu/amd/amd_iommu.h-41-void amd_iommu_disable(void);\ndrivers/iommu/amd/amd_iommu.h=42=int amd_iommu_reenable(int mode);\ndrivers/iommu/amd/amd_iommu.h:43:int amd_iommu_enable_faulting(unsigned int cpu);\ndrivers/iommu/amd/amd_iommu.h-44-extern int amd_iommu_guest_ir;\n--\ndrivers/iommu/amd/amd_iommu.h=83=void __init amd_iommu_free_ppr_log(struct amd_iommu *iommu);\ndrivers/iommu/amd/amd_iommu.h:84:void amd_iommu_enable_ppr_log(struct amd_iommu *iommu);\ndrivers/iommu/amd/amd_iommu.h-85-void amd_iommu_poll_ppr_log(struct amd_iommu *iommu);\n--\ndrivers/iommu/amd/init.c=228=static enum iommu_init_state init_state = IOMMU_START_STATE;\ndrivers/iommu/amd/init.c-229-\ndrivers/iommu/amd/init.c:230:static int amd_iommu_enable_interrupts(void);\ndrivers/iommu/amd/init.c-231-static void init_device_table_dma(struct amd_iommu_pci_seg *pci_seg);\n--\ndrivers/iommu/amd/init.c=3001=static void enable_iommus_ppr(void)\n--\ndrivers/iommu/amd/init.c-3008-\tfor_each_iommu(iommu)\ndrivers/iommu/amd/init.c:3009:\t\tamd_iommu_enable_ppr_log(iommu);\ndrivers/iommu/amd/init.c-3010-}\n--\ndrivers/iommu/amd/init.c=3117=static void amd_iommu_resume(void *data)\n--\ndrivers/iommu/amd/init.c-3132-\tiommu_enable_event_buffer();\ndrivers/iommu/amd/init.c:3133:\tamd_iommu_enable_interrupts();\ndrivers/iommu/amd/init.c-3134-}\n--\ndrivers/iommu/amd/init.c=3286=static int __init early_amd_iommu_init(void)\n--\ndrivers/iommu/amd/init.c-3399-\ndrivers/iommu/amd/init.c:3400:static int amd_iommu_enable_interrupts(void)\ndrivers/iommu/amd/init.c-3401-{\n--\ndrivers/iommu/amd/init.c=3540=static int __init state_next(void)\n--\ndrivers/iommu/amd/init.c-3589-\tcase IOMMU_PCI_INIT:\ndrivers/iommu/amd/init.c:3590:\t\tret = amd_iommu_enable_interrupts();\ndrivers/iommu/amd/init.c-3591-\t\tinit_state = ret ? IOMMU_INIT_ERROR : IOMMU_INTERRUPTS_EN;\n--\ndrivers/iommu/amd/init.c=3629=static int __init iommu_go_to_state(enum iommu_init_state state)\n--\ndrivers/iommu/amd/init.c-3671-#ifdef CONFIG_IRQ_REMAP\ndrivers/iommu/amd/init.c:3672:int __init amd_iommu_prepare(void)\ndrivers/iommu/amd/init.c-3673-{\n--\ndrivers/iommu/amd/init.c-3686-\ndrivers/iommu/amd/init.c:3687:int __init amd_iommu_enable(void)\ndrivers/iommu/amd/init.c-3688-{\n--\ndrivers/iommu/amd/init.c=3704=int amd_iommu_reenable(int mode)\n--\ndrivers/iommu/amd/init.c-3710-\ndrivers/iommu/amd/init.c:3711:int amd_iommu_enable_faulting(unsigned int cpu)\ndrivers/iommu/amd/init.c-3712-{\n--\ndrivers/iommu/amd/iommu.c=2600=int amd_iommu_perfopt_restore(struct amd_iommu *iommu)\n--\ndrivers/iommu/amd/iommu.c-2613-\ndrivers/iommu/amd/iommu.c:2614:int amd_iommu_enable_perfopt(struct pci_dev *pdev)\ndrivers/iommu/amd/iommu.c-2615-{\n--\ndrivers/iommu/amd/iommu.c-2673-}\ndrivers/iommu/amd/iommu.c:2674:EXPORT_SYMBOL_GPL(amd_iommu_enable_perfopt);\ndrivers/iommu/amd/iommu.c-2675-\ndrivers/iommu/amd/iommu.c=2676=void amd_iommu_disable_perfopt(struct pci_dev *pdev)\n--\ndrivers/iommu/amd/iommu.c-2691-\t * sees a normally-capable device. See the locking note in\ndrivers/iommu/amd/iommu.c:2692:\t * amd_iommu_enable_perfopt().\ndrivers/iommu/amd/iommu.c-2693-\t */\n--\ndrivers/iommu/amd/iommu.c=3961=struct irq_remap_ops amd_iommu_irq_ops = {\ndrivers/iommu/amd/iommu.c:3962:\t.prepare\t\t= amd_iommu_prepare,\ndrivers/iommu/amd/iommu.c:3963:\t.enable\t\t\t= amd_iommu_enable,\ndrivers/iommu/amd/iommu.c-3964-\t.disable\t\t= amd_iommu_disable,\ndrivers/iommu/amd/iommu.c-3965-\t.reenable\t\t= amd_iommu_reenable,\ndrivers/iommu/amd/iommu.c:3966:\t.enable_faulting\t= amd_iommu_enable_faulting,\ndrivers/iommu/amd/iommu.c-3967-};\n--\ndrivers/iommu/amd/ppr.c=20=int __init amd_iommu_alloc_ppr_log(struct amd_iommu *iommu)\n--\ndrivers/iommu/amd/ppr.c-26-\ndrivers/iommu/amd/ppr.c:27:void amd_iommu_enable_ppr_log(struct amd_iommu *iommu)\ndrivers/iommu/amd/ppr.c-28-{\n--\ninclude/linux/amd-iommu.h=76=static inline bool amd_iommu_sev_tio_supported(void) { return false; }\n--\ninclude/linux/amd-iommu.h-79-#ifdef CONFIG_AMD_IOMMU\ninclude/linux/amd-iommu.h:80:int amd_iommu_enable_perfopt(struct pci_dev *pdev);\ninclude/linux/amd-iommu.h-81-void amd_iommu_disable_perfopt(struct pci_dev *pdev);\ninclude/linux/amd-iommu.h-82-#else\ninclude/linux/amd-iommu.h:83:static inline int amd_iommu_enable_perfopt(struct pci_dev *pdev)\ninclude/linux/amd-iommu.h-84-{\n"
} |
| 23/2 | 2026/10/18 07:59 | llm | patch-evaluator |
0mModel:gemini-3.8-flash Args: null Results: null Tokens: input: 16756 output: 36 thoughts: 15 Thoughts: Okay, here's my attempt at summarizing that thought process, tailored for an expert audience: **Analyzing the AMD IOMMU Initialization** Alright, let's dive in. The core question is: what's going on inside `amd_iommu_init`? I need to understand its role within the broader IOMMU setup. My focus is on the AMD implementation, so I'm looking at the specific AMD-related code path, not the generic IOMMU framework. I'm going to follow the function calls from `amd_iommu_init` to get a sense of the process. I want to build a mental map of the initialization steps, the hardware configuration, and the data structures involved. I'll be looking for things like: * **Enumeration:** How is the IOMMU hardware identified and its presence verified? * **Registers:** Which registers are being accessed, and what configurations are being written? Any interesting bits or bitfields? * **Memory mapping:** How is the IOMMU's memory space mapped? Are there any special considerations for physical address translation? * **Interrupts:** How are interrupts set up for the IOMMU, and what kind of interrupt handling is involved? * **Root complex:** Am I going to be looking at how to bind to the root complex or something more advanced? * **Devices:** How are the IOMMU's capabilities exposed to the system and drivers? Is there a driver model in use, or something more direct? I need to quickly grasp its initialization sequence. I'm not just interested in the "what" but the "why" -- the underlying logic and rationale behind the implementation choices. Any optimization considerations or potential pitfalls are also going to be interesting. |
| 24/2 | 2026/10/18 07:59 | tool | grepper |
0mArgs:{
"Expression": "amd_iommu_init",
"PathPrefixes": [
"drivers/iommu/amd/"
]
}Results: {
"Output": "drivers/iommu/amd/amd_iommu.h=52=int amd_iommu_perfopt_restore(struct amd_iommu *iommu);\n--\ndrivers/iommu/amd/amd_iommu.h-54-/* Protection domain ops */\ndrivers/iommu/amd/amd_iommu.h:55:void amd_iommu_init_identity_domain(void);\ndrivers/iommu/amd/amd_iommu.h-56-struct protection_domain *protection_domain_alloc(void);\n--\ndrivers/iommu/amd/init.c=2292=static void print_iommu_info(void)\n--\ndrivers/iommu/amd/init.c-2330-\ndrivers/iommu/amd/init.c:2331:static int __init amd_iommu_init_pci(void)\ndrivers/iommu/amd/init.c-2332-{\n--\ndrivers/iommu/amd/init.c-2337-\t/* Init global identity domain before registering IOMMU */\ndrivers/iommu/amd/init.c:2338:\tamd_iommu_init_identity_domain();\ndrivers/iommu/amd/init.c-2339-\n--\ndrivers/iommu/amd/init.c=3254=static void __init ivinfo_init(void *ivrs)\n--\ndrivers/iommu/amd/init.c-3260- * This is the hardware init function for AMD IOMMU in the system.\ndrivers/iommu/amd/init.c:3261: * This function is called either from amd_iommu_init or from the interrupt\ndrivers/iommu/amd/init.c-3262- * remapping setup code.\n--\ndrivers/iommu/amd/init.c-3285- */\ndrivers/iommu/amd/init.c:3286:static int __init early_amd_iommu_init(void)\ndrivers/iommu/amd/init.c-3287-{\n--\ndrivers/iommu/amd/init.c=3540=static int __init state_next(void)\n--\ndrivers/iommu/amd/init.c-3559-\tcase IOMMU_IVRS_DETECTED:\ndrivers/iommu/amd/init.c:3560:\t\tret = early_amd_iommu_init();\ndrivers/iommu/amd/init.c-3561-\t\tinit_state = ret ? IOMMU_INIT_ERROR : IOMMU_ACPI_FINISHED;\n--\ndrivers/iommu/amd/init.c-3585-\ndrivers/iommu/amd/init.c:3586:\t\tret = amd_iommu_init_pci();\ndrivers/iommu/amd/init.c-3587-\t\tinit_state = ret ? IOMMU_INIT_ERROR : IOMMU_PCI_INIT;\n--\ndrivers/iommu/amd/init.c=3711=int amd_iommu_enable_faulting(unsigned int cpu)\n--\ndrivers/iommu/amd/init.c-3722- */\ndrivers/iommu/amd/init.c:3723:static int __init amd_iommu_init(void)\ndrivers/iommu/amd/init.c-3724-{\n--\ndrivers/iommu/amd/init.c=3770=void __init amd_iommu_detect(void)\n--\ndrivers/iommu/amd/init.c-3778-\tiommu_detected = 1;\ndrivers/iommu/amd/init.c:3779:\tx86_init.iommu.iommu_init = amd_iommu_init;\ndrivers/iommu/amd/init.c-3780-\treturn;\n--\ndrivers/iommu/amd/iommu.c=3182=static const struct iommu_domain_ops identity_domain_ops = {\n--\ndrivers/iommu/amd/iommu.c-3185-\ndrivers/iommu/amd/iommu.c:3186:void amd_iommu_init_identity_domain(void)\ndrivers/iommu/amd/iommu.c-3187-{\n"
} |
| 25/2 | 2026/10/18 07:59 | llm | patch-evaluator |
0mModel:gemini-3.8-flash Args: null Results: null Tokens: input: 18299 output: 20 thoughts: 2005 Thoughts: **Reaching AMD IOMMU Initialization Code with Syzkaller** Alright, let's break this down. First, `amd_iommu_detect` sets up the AMD IOMMU initialization process. This includes calling `amd_iommu_init`, which then calls `iommu_go_to_state`, and finally, the ACPI IVRS table is parsed via `early_amd_iommu_init`. This all occurs during the early boot phase, specifically in the x86 platform initialization before userspace is even running. I know QEMU supports AMD IOMMU, as indicated by the `-device amd-iommu` option. The question is, can syzkaller reach this code? Syzkaller's primary method is fuzzing running kernels by executing syscalls, meaning it doesn't directly manipulate ACPI tables or reboot QEMU with modified ACPI configurations. Time to re-read those triage guidelines carefully. The core philosophy is all about reachability. Fuzzing is only effective if the code *executes* in standard virtualized environments. The guidelines explicitly state that structurally unreachable code, like hardware-specific drivers not emulated in QEMU, should not be fuzzed. And that we should not blindly trust "no functional change" or "refactoring" claims. Assertions in *reachable* code must be fuzzed, though. The guidelines also list when to return `WorthFuzzing=false`. Non-kernel changes, unreachable hardware (ASIC/PCIe cards not emulated), and unreachable execution paths are all out. And when to return `WorthFuzzing=true`. Core subsystems, refactorings of reachable structures, and *any* introduction of new or modified assertions in reachable paths are *in*. Now, the question is, can syzkaller actually touch those functions? We're dealing with `__init` functions. These are functions that run only once during kernel boot and are freed from memory by `free_initmem()` after initialization. Specifically, can syzkaller reach `init_memory_definitions` or `ivrs_block_type_ivmd`? Remember, `init_memory_definitions` is explicitly marked `__init`, meaning it resides in `.init.text` which is freed *before* userspace starts. Checking the code, `ivrs_block_type_ivmd` is static and only called by `init_memory_definitions`. `init_memory_definitions` is also static, marked `__init`, and only called by `early_amd_iommu_init()`. `early_amd_iommu_init` is static and `__init`, and it's called by `state_next()`. `state_next` is also static and `__init`, and called by `iommu_go_to_state()`. Finally, `iommu_go_to_state` is static and `__init`. Every caller of `iommu_go_to_state` (`amd_iommu_prepare`, `amd_iommu_enable`, `amd_iommu_init`, `amd_iommu_detect`) is marked `__init`! Let's double check if `amd_iommu_prepare` or `amd_iommu_enable` is called *after* boot. We find these functions in `amd_iommu_irq_ops`, and both `amd_iommu_prepare` and `amd_iommu_enable` are indeed marked `__init`! And so is `amd_iommu_init` and `amd_iommu_detect`! Why are `.prepare` and `.enable` `__init`? Because IRQ remapping setup occurs during early boot. Therefore, this code is *unreachable* by syzkaller after boot, because it is freed from memory before userspace starts. The answer is clear: the changes are in `__init` functions, therefore they are *not* worth fuzzing. |
| 26/2 | 2026/10/18 07:59 | tool | grepper |
0mArgs:{
"Expression": "remap_ops.*prepare"
}Results: {
"Output": "drivers/iommu/intel/irq_remapping.c=65=static struct hpet_scope ir_hpet[MAX_HPET_TBS];\n--\ndrivers/iommu/intel/irq_remapping.c-73- * Note:\ndrivers/iommu/intel/irq_remapping.c:74: * intel_irq_remap_ops.{supported,prepare,enable,disable,reenable} are called\ndrivers/iommu/intel/irq_remapping.c-75- * in single-threaded environment with interrupt disabled, so no need to tabke\n--\ndrivers/iommu/irq_remapping.c=100=int __init irq_remapping_prepare(void)\n--\ndrivers/iommu/irq_remapping.c-105-\tif (IS_ENABLED(CONFIG_INTEL_IOMMU) \u0026\u0026\ndrivers/iommu/irq_remapping.c:106:\t intel_irq_remap_ops.prepare() == 0)\ndrivers/iommu/irq_remapping.c-107-\t\tremap_ops = \u0026intel_irq_remap_ops;\n--\ndrivers/iommu/irq_remapping.c-111-\telse if (IS_ENABLED(CONFIG_HYPERV) \u0026\u0026\ndrivers/iommu/irq_remapping.c:112:\t\t hyperv_irq_remap_ops.prepare() == 0)\ndrivers/iommu/irq_remapping.c-113-\t\tremap_ops = \u0026hyperv_irq_remap_ops;\n"
} |
| 27/2 | 2026/10/18 07:59 | llm | patch-evaluator |
0mModel:gemini-3.8-flash Args: null Results: null Tokens: input: 21602 output: 33 thoughts: 43 Thoughts: Okay, let's see... **Initializing and Enabling Interrupt Remapping: A Quick Check** Hmm, so `irq_remapping_prepare()` is tagged with `__init` as well, interesting. That means it's only executed at boot-up, which makes sense for setting up the initial hardware configuration. I need to make sure I understand the full sequence. Now, what's happening with `irq_remapping_enable`? Is that also `__init`, or is it called later? I should probably double-check the `irq_remapping.c` file itself to get the full picture. Let's dive in there and see what we can find. |
| 28/2 | 2026/10/18 07:59 | tool | grepper |
0mArgs:{
"Expression": "remap_ops.*enable",
"PathPrefixes": [
"drivers/iommu/"
]
}Results: {
"Output": "drivers/iommu/intel/irq_remapping.c=65=static struct hpet_scope ir_hpet[MAX_HPET_TBS];\n--\ndrivers/iommu/intel/irq_remapping.c-73- * Note:\ndrivers/iommu/intel/irq_remapping.c:74: * intel_irq_remap_ops.{supported,prepare,enable,disable,reenable} are called\ndrivers/iommu/intel/irq_remapping.c-75- * in single-threaded environment with interrupt disabled, so no need to tabke\n--\ndrivers/iommu/irq_remapping.c=120=int __init irq_remapping_enable(void)\n--\ndrivers/iommu/irq_remapping.c-123-\ndrivers/iommu/irq_remapping.c:124:\tif (!remap_ops-\u003eenable)\ndrivers/iommu/irq_remapping.c-125-\t\treturn -ENODEV;\ndrivers/iommu/irq_remapping.c-126-\ndrivers/iommu/irq_remapping.c:127:\tret = remap_ops-\u003eenable();\ndrivers/iommu/irq_remapping.c-128-\n--\ndrivers/iommu/irq_remapping.c=141=int irq_remapping_reenable(int mode)\ndrivers/iommu/irq_remapping.c-142-{\ndrivers/iommu/irq_remapping.c:143:\tif (irq_remapping_enabled \u0026\u0026 remap_ops-\u003ereenable)\ndrivers/iommu/irq_remapping.c:144:\t\treturn remap_ops-\u003ereenable(mode);\ndrivers/iommu/irq_remapping.c-145-\n--\ndrivers/iommu/irq_remapping.c=149=int __init irq_remap_enable_fault_handling(void)\n--\ndrivers/iommu/irq_remapping.c-153-\ndrivers/iommu/irq_remapping.c:154:\tif (!remap_ops-\u003eenable_faulting)\ndrivers/iommu/irq_remapping.c-155-\t\treturn -ENODEV;\n--\ndrivers/iommu/irq_remapping.c-157-\tcpuhp_setup_state(CPUHP_AP_ONLINE_DYN, \"dmar:enable_fault_handling\",\ndrivers/iommu/irq_remapping.c:158:\t\t\t remap_ops-\u003eenable_faulting, NULL);\ndrivers/iommu/irq_remapping.c-159-\ndrivers/iommu/irq_remapping.c:160:\treturn remap_ops-\u003eenable_faulting(smp_processor_id());\ndrivers/iommu/irq_remapping.c-161-}\n"
} |
| 29/2 | 2026/10/18 07:59 | llm | patch-evaluator |
0mModel:gemini-3.8-flash Args: null Results: null Tokens: input: 22574 output: 23 thoughts: 678 Thoughts: **Analyzing the Initialization Sequence** Okay, so `irq_remapping_enable` is also marked as `__init`, which is a key detail. And then there's `init_memory_definitions` – is that accessible by syzkaller? The answer, unequivocally, is NO. Why not? Because `init_memory_definitions` resides within `.init.text`, which is marked `__init`. This means that it's executed during the kernel's early boot process and then freed. Syzkaller, however, operates in userspace *after* the kernel has already booted and `free_initmem()` has purged all the `__init` code and data. Therefore, syzkaller cannot interact with functions in `__init`. So the fundamental issue is this: syzkaller works in userspace, and calling a function in `.init.text` after the initial boot process would result in either a page fault or a crash, since those memory pages are poisoned, unmapped, or freed. User space syscalls, by definition, can't reach functions defined in `.init`. Now, is there *any* other place where `ivrs_block_type_ivmd` is used, or where `init_memory_definitions` is even called? I have to re-examine the patch. Looking at the diff, it's clear that the code checks the `ivmd_header` for various types, and that `init_memory_definitions` processes these headers based on their flags. Let's see if the commit message offers more context. |
| 30/2 | 2026/10/18 07:59 | tool | grepper |
0mArgs:{
"Expression": "ivrs_block_type_ivmd"
}Results: {
"Output": "drivers/iommu/amd/init.c=2657=static int __init init_unity_map_range(struct ivmd_header *m,\n--\ndrivers/iommu/amd/init.c-2718-\ndrivers/iommu/amd/init.c:2719:static bool ivrs_block_type_ivmd(u8 type)\ndrivers/iommu/amd/init.c-2720-{\n--\ndrivers/iommu/amd/init.c=2729=static int __init init_memory_definitions(struct acpi_table_header *table)\n--\ndrivers/iommu/amd/init.c-2739-\t\tp += m-\u003elength;\ndrivers/iommu/amd/init.c:2740:\t\tif (!ivrs_block_type_ivmd(m-\u003etype))\ndrivers/iommu/amd/init.c-2741-\t\t\tcontinue;\n"
} |
| 31/2 | 2026/10/18 08:00 | llm | patch-evaluator |
0mModel:gemini-3.8-flash Args: null Results: null Tokens: input: 23851 output: 33 thoughts: 59 Thoughts: Okay, let's see what we're dealing with here. **Investigating the IOMMU Module Build Configuration** My initial thought is to figure out the build configuration for this IOMMU module. Specifically, I need to determine if it can be loaded dynamically. The core of this investigation will revolve around the `drivers/iommu/amd/` directory, and whether the AMD IOMMU driver can be built as a loadable module. To get the necessary information, I should dive into the relevant Kconfig files. I'll start by examining `drivers/iommu/amd/Kconfig` directly, and if that doesn't provide the answers, I'll broaden the scope to include the general `drivers/iommu/Kconfig` file. That should give me a solid understanding of how this module is configured within the kernel build system. |
| 32/2 | 2026/10/18 08:00 | tool | grepper |
0mArgs:{
"Expression": "config AMD_IOMMU",
"PathPrefixes": [
"drivers/iommu/"
]
}Results: {
"Output": "drivers/iommu/amd/Kconfig-2-# AMD IOMMU support\ndrivers/iommu/amd/Kconfig:3:config AMD_IOMMU\ndrivers/iommu/amd/Kconfig-4-\tbool \"AMD IOMMU support\"\n--\ndrivers/iommu/amd/Kconfig-32-\ndrivers/iommu/amd/Kconfig:33:config AMD_IOMMU_IOMMUFD\ndrivers/iommu/amd/Kconfig-34-\tbool \"Enable IOMMUFD features for AMD IOMMU (EXPERIMENTAL)\"\n--\ndrivers/iommu/amd/Kconfig-42-\ndrivers/iommu/amd/Kconfig:43:config AMD_IOMMU_DEBUGFS\ndrivers/iommu/amd/Kconfig-44-\tbool \"Enable AMD IOMMU internals in DebugFS\"\n"
} |
| 33/2 | 2026/10/18 08:00 | llm | patch-evaluator |
0mModel:gemini-3.8-flash Args: null Results: null Tokens: input: 24343 output: 35 thoughts: 64 Thoughts: **Examining the AMD IOMMU Configuration** Okay, so `CONFIG_AMD_IOMMU` is a boolean, straight up. I'm already mentally dismissing any attempt to build it as a module – that's not how booleans work! You can't have an object file conditional on a boolean that way, (`obj-$(CONFIG_AMD_IOMMU) += amd_iommu.o` or built-in, no way!). I need to understand how this is handled, so the next logical step is to check the `drivers/iommu/amd/Makefile`. That's where I expect to find the actual logic determining how this configuration option influences the build process. Time to dig in and see how they are handling this. |
| 34/2 | 2026/10/18 08:00 | tool | read-file |
0mArgs:{
"File": "drivers/iommu/amd/Makefile",
"FirstLine": 1,
"LineCount": 20
}Results: {
"Contents": " 1:\t# SPDX-License-Identifier: GPL-2.0-only\n 2:\tobj-y += iommu.o init.o quirks.o ppr.o pasid.o\n 3:\tobj-$(CONFIG_AMD_IOMMU_IOMMUFD) += iommufd.o nested.o\n 4:\tobj-$(CONFIG_AMD_IOMMU_DEBUGFS) += debugfs.o\n"
} |
| 35/2 | 2026/10/18 08:00 | llm | patch-evaluator |
0mModel:gemini-3.8-flash Args: null Results: null Tokens: input: 24717 output: 127 thoughts: 1326 Thoughts: **Unreachable Code Analysis: `drivers/iommu/amd/`**
Okay, let's break this down. The code in `drivers/iommu/amd/` and specifically the `init_memory_definitions` function, it's all built-in when `CONFIG_AMD_IOMMU` is enabled. And, critically, `init_memory_definitions` is marked `__init`. Right, and that means it's *only* called during kernel boot. I know that much. It's parsing the ACPI IVRS table (`ivrs_base`) that the system firmware (BIOS/UEFI/etc.) provides *at boot*.
Even if someone spun up a VM with an AMD IOMMU, that ACPI IVRS table is essentially static for that boot, constructed by the hypervisor (SeaBIOS, OVMF, QEMU). Syzkaller can't mutate that table at runtime. And userspace? Forget about it. They can't call `init_memory_definitions()` because: 1. It's marked `__init` and vanishes when the boot sequence concludes. 2. There's no exposed interface (syscall, ioctl, sysfs, debugfs, netlink) to trigger a re-parse or reload of that IVRS table.
Now, let's re-read the instructions: Reachability is key. Fuzzing can only find bugs in code that *can execute* in a standard virtualized environment. The rules say that if the modified code is *structurally unreachable*, we should not fuzz it, no matter if there are assertions or complex logic.
Then the rules clarify: unreachable execution paths: Driver teardown callbacks only executed during physical PCI hot-unplug, or manual sysfs driver unbinding. And code paths exclusive to architectures other than the target architecture.
So, let's think carefully about `__init` code. Can syzkaller even touch early boot ACPI table parsing code? Syzkaller fuzzes syscalls and user-space inputs or emulated devices. It *doesn't* reboot the VM for each test case or fuzz the ACPI tables during `__init`.
Also, `init_memory_definitions` is in `.init.text`. The `.init.text` memory gets freed via `free_initmem()` *before* init (PID 1) runs. Meaning, at runtime, when syzkaller is running, `init_memory_definitions` *doesn't even exist in memory*! It's completely unreachable.
Okay, let's double-check. Is there *any* possibility of reaching this code? Could `ivrs_block_type_ivmd` be called from somewhere else? Let's grep. Aha! It's only defined and called in `drivers/iommu/amd/init.c` within `init_memory_definitions`.
```c
static bool ivrs_block_type_ivmd(u8 type)
{
if (type == ACPI_IVMD_TYPE ||
type == ACPI_IVMD_TYPE_ALL ||
type == ACPI_IVMD_TYPE_RANGE)
return true;
return false;
}
```
And in `init_memory_definitions`:
```c
while (p < end) {
m = (struct ivmd_header *)p;
p += m->length;
if (!ivrs_block_type_ivmd(m->type))
continue;
if (m->flags & (IVMD_FLAG_UNITY_MAP | IVMD_FLAG_EXCL_RANGE))
init_unity_map_range(m, table);
}
```
Nowhere else. And `init_memory_definitions` itself is `__init`. It's called by `early_amd_iommu_init()`, which is `__init`. Which is called by `state_next()`, which is `__init`. Which is called by `iommu_go_to_state()`, which is `__init`. Which is called during boot by `amd_iommu_detect` / `amd_iommu_init` / `amd_iommu_prepare` / `amd_iommu_enable`, all `__init`. This is *all* boot-time stuff. None of this is callable after boot.
Therefore, the modified code is *structurally unreachable* by syzkaller during runtime fuzzing. It's solely in early kernel boot (in `__init`) to parse firmware-provided ACPI IVRS tables and is discarded from memory before userspace starts.
Alright, let's define these parameters and call `set-results
|
| 36/2 | 2026/10/18 08:00 | tool | set-results |
0mArgs:{
"EnableConfigs": [],
"FocusSymbols": [],
"Reasoning": "The patch modifies `init_memory_definitions()` and introduces `ivrs_block_type_ivmd()` in `drivers/iommu/amd/init.c`. These functions execute exclusively during early kernel boot (`__init`) while parsing the firmware-provided ACPI IVRS tables. Because this code runs prior to userspace execution and is subsequently freed from memory via `free_initmem()`, it is structurally unreachable by syzkaller runtime fuzzing.",
"WorthFuzzing": false
}Results: {
"EnableConfigs": null,
"FocusSymbols": [],
"Reasoning": "The patch modifies `init_memory_definitions()` and introduces `ivrs_block_type_ivmd()` in `drivers/iommu/amd/init.c`. These functions execute exclusively during early kernel boot (`__init`) while parsing the firmware-provided ACPI IVRS tables. Because this code runs prior to userspace execution and is subsequently freed from memory via `free_initmem()`, it is structurally unreachable by syzkaller runtime fuzzing.",
"WorthFuzzing": false
} |
| 37/1 | 2026/10/18 08:00 | action | If |
0mArgs:{
"WorthFuzzing": false
}Results: null |
| Total Calls | Total Tokens | Avg Tokens | Total Duration (Seconds) | Avg Duration (Seconds) |
|---|
| Total Calls | Total Duration (Seconds) | Avg Duration (Seconds) |
|---|