AI Trajectory


Trajectory: (Expand/Collapse All)
Seq Timestamp Type Name Duration
0/0 2026/08/14 11:37 flow patch-triage
1m Args: 
null

Results: 
{
  "EnableConfigs": null,
  "FocusSymbols": [],
  "KMSANReasoning": "",
  "NeedsKMSAN": false,
  "Reasoning": "The patch modifies the Marvell OcteonTX2 driver, which is a vendor-specific hardware NIC driver. This hardware is not emulated in standard QEMU, so the code cannot be reached in virtualized environments like GCE or QEMU.",
  "WorthFuzzing": false
}
1/1 2026/08/14 11:37 action read-patch-diff
0m Args: 
null

Results: 
{
  "PatchDiff": "commit bbe07f066d4f1615c3d6dc9a89ca2775bed610e9\nAuthor: syz-cluster \u003ctriage@syzkaller.com\u003e\nDate:   Fri Aug 14 11:37:51 2026 +0000\n\n    syz-cluster: applied patch under review\n\ndiff --git a/Documentation/networking/devlink/octeontx2.rst b/Documentation/networking/devlink/octeontx2.rst\nindex 84206537aedbc..1463cb52ae547 100644\n--- a/Documentation/networking/devlink/octeontx2.rst\n+++ b/Documentation/networking/devlink/octeontx2.rst\n@@ -77,3 +77,12 @@ The ``octeontx2 PF`` driver implements the following driver-specific parameters.\n      - Set the maximum number of unicast filters that can be programmed for\n        the device. This can be used to achieve better device resource\n        utilization, avoiding over consumption of unused MCAM table entries.\n+   * - ``mac_stats_reset``\n+     - bool\n+     - runtime\n+     - One-shot trigger to reset CGX/RPM MAC hardware statistics.\n+       Write true to reset the counters; reading this parameter always returns\n+       false. Supported only on CGX/RPM mapped PF netdevs. The reset fails with\n+       ``-EBUSY`` when the CGX port is in use by more than one interface, such\n+       as when the PF netdev and one or more VF netdevs are active. Other\n+       failures return ``-EIO``.\ndiff --git a/drivers/net/ethernet/marvell/octeontx2/af/rvu_cgx.c b/drivers/net/ethernet/marvell/octeontx2/af/rvu_cgx.c\nindex 87d21889dc49e..7e09ca25101d4 100644\n--- a/drivers/net/ethernet/marvell/octeontx2/af/rvu_cgx.c\n+++ b/drivers/net/ethernet/marvell/octeontx2/af/rvu_cgx.c\n@@ -649,7 +649,7 @@ int rvu_mbox_handler_cgx_stats_rst(struct rvu *rvu, struct msg_req *req,\n \t */\n \tif (parent_pf-\u003ecgx_users \u003e 1) {\n \t\tdev_info(rvu-\u003edev, \"CGX busy, could not reset statistics\\n\");\n-\t\treturn 0;\n+\t\treturn -EBUSY;\n \t}\n \n \trvu_get_cgx_lmac_id(rvu-\u003epf2cgxlmac_map[pf], \u0026cgx_idx, \u0026lmac);\ndiff --git a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_devlink.c b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_devlink.c\nindex 4a5ce0e67dda8..daa8fb37f392c 100644\n--- a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_devlink.c\n+++ b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_devlink.c\n@@ -125,10 +125,43 @@ static int otx2_dl_ucast_flt_cnt_validate(struct devlink *devlink, u32 id,\n \treturn 0;\n }\n \n+static int otx2_dl_mac_stats_reset_get(struct devlink *devlink, u32 id,\n+\t\t\t\t       struct devlink_param_gset_ctx *ctx,\n+\t\t\t\t       struct netlink_ext_ack *extack)\n+{\n+\t/* This is a one-shot trigger, so it has no state */\n+\tctx-\u003eval.vbool = false;\n+\treturn 0;\n+}\n+\n+static int otx2_dl_mac_stats_reset_set(struct devlink *devlink, u32 id,\n+\t\t\t\t       struct devlink_param_gset_ctx *ctx,\n+\t\t\t\t       struct netlink_ext_ack *extack)\n+{\n+\tstruct otx2_devlink *otx2_dl = devlink_priv(devlink);\n+\tstruct otx2_nic *pfvf = otx2_dl-\u003epfvf;\n+\tint err;\n+\n+\tif (!ctx-\u003eval.vbool)\n+\t\treturn 0;\n+\n+\terr = otx2_reset_mac_stats(pfvf);\n+\tif (err == -EBUSY) {\n+\t\tNL_SET_ERR_MSG_MOD(extack,\n+\t\t\t\t   \"CGX port shared by multiple interfaces, cannot reset MAC stats\");\n+\t\treturn -EBUSY;\n+\t} else if (err) {\n+\t\treturn -EIO;\n+\t}\n+\n+\treturn 0;\n+}\n+\n enum otx2_dl_param_id {\n \tOTX2_DEVLINK_PARAM_ID_BASE = DEVLINK_PARAM_GENERIC_ID_MAX,\n \tOTX2_DEVLINK_PARAM_ID_MCAM_COUNT,\n \tOTX2_DEVLINK_PARAM_ID_UCAST_FLT_CNT,\n+\tOTX2_DEVLINK_PARAM_ID_MAC_STATS_RST,\n };\n \n static const struct devlink_param otx2_dl_params[] = {\n@@ -142,6 +175,12 @@ static const struct devlink_param otx2_dl_params[] = {\n \t\t\t     BIT(DEVLINK_PARAM_CMODE_RUNTIME),\n \t\t\t     otx2_dl_ucast_flt_cnt_get, otx2_dl_ucast_flt_cnt_set,\n \t\t\t     otx2_dl_ucast_flt_cnt_validate),\n+\tDEVLINK_PARAM_DRIVER(OTX2_DEVLINK_PARAM_ID_MAC_STATS_RST,\n+\t\t\t     \"mac_stats_reset\", DEVLINK_PARAM_TYPE_BOOL,\n+\t\t\t     BIT(DEVLINK_PARAM_CMODE_RUNTIME),\n+\t\t\t     otx2_dl_mac_stats_reset_get,\n+\t\t\t     otx2_dl_mac_stats_reset_set,\n+\t\t\t     NULL),\n };\n \n #ifdef CONFIG_RVU_ESWITCH\n"
}
2/1 2026/08/14 11:37 agent patch-evaluator
1m Model: 
best-expensive

Args: 
null

Results: 
{
  "EnableConfigs": null,
  "FocusSymbols": [],
  "Reasoning": "The patch modifies the Marvell OcteonTX2 driver, which is a vendor-specific hardware NIC driver. This hardware is not emulated in standard QEMU, so the code cannot be reached in virtualized environments like GCE or QEMU.",
  "WorthFuzzing": false
}

Instruction: 
You are an expert Linux kernel maintainer.
Your job is to review a provided patch series and determine
if it makes functional changes to the kernel that should be fuzzed.

IMPORTANT: The changes have ALREADY been applied and committed as the HEAD commit in
your workspace. Do NOT rely on your internal knowledge of the kernel. You must actively
use your code access tools to examine the actual source code and confirm any assumptions.

Return WorthFuzzing=false if the patch only contains:
- Modifications to Documentation/, Kconfig files, or code comments.
- Purely decorative changes, such as logging (e.g., pr_err, printk) or tracepoints.
- Changes to numeric constants or macros that do not functionally alter execution flow.
- Code paths that are impossible to reach in virtualized environments like GCE or QEMU,
  even when utilizing software-emulated hardware (e.g., usb gadget, mac80211_hwsim).
- Code in vendor-specific PCIe switch, SmartNIC, or GPU drivers (e.g., mlxsw, pds_core, qed,
  ionic, amdgpu) that require physical PCIe hardware cards not emulated in standard QEMU.
- Driver .remove, .shutdown, or pci_unregister_driver teardown callbacks (e.g., igb_remove)
  that are executed only during PCI hot-unplug or sysfs driver unbind operations.

If it modifies reachable core kernel logic, drivers, or architectures, use your code search
tools to verify the code can be executed, then return WorthFuzzing=true.

When returning WorthFuzzing=true, you MUST ALSO:
1. Extract any specific kernel functions that should be heavily fuzzed into FocusSymbols.
   Avoid listing generic hot-path functions to prevent skewed test distributions.
   Prefer non-static, non-inlined API entrypoint functions over internal static helper functions
   (which are inlined by the compiler and do not have distinct symbol addresses).
2. Identify any specific CONFIG_ options required to properly test this new/modified feature.
   Go and look into the Kconfig files and check for ifdefs around the code, do not make assumptions.
   Also check "depends on" lines in Kconfig to include any non-standard parent subsystem configs
   needed for Kbuild to compile the code statically into vmlinux. List them in the EnableConfigs
   output array, and DO NOT add a '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: 
For your convenience, here is the diff of the changes:
commit bbe07f066d4f1615c3d6dc9a89ca2775bed610e9
Author: syz-cluster <triage@syzkaller.com>
Date:   Fri Aug 14 11:37:51 2026 +0000

    syz-cluster: applied patch under review

diff --git a/Documentation/networking/devlink/octeontx2.rst b/Documentation/networking/devlink/octeontx2.rst
index 84206537aedbc..1463cb52ae547 100644
--- a/Documentation/networking/devlink/octeontx2.rst
+++ b/Documentation/networking/devlink/octeontx2.rst
@@ -77,3 +77,12 @@ The ``octeontx2 PF`` driver implements the following driver-specific parameters.
      - Set the maximum number of unicast filters that can be programmed for
        the device. This can be used to achieve better device resource
        utilization, avoiding over consumption of unused MCAM table entries.
+   * - ``mac_stats_reset``
+     - bool
+     - runtime
+     - One-shot trigger to reset CGX/RPM MAC hardware statistics.
+       Write true to reset the counters; reading this parameter always returns
+       false. Supported only on CGX/RPM mapped PF netdevs. The reset fails with
+       ``-EBUSY`` when the CGX port is in use by more than one interface, such
+       as when the PF netdev and one or more VF netdevs are active. Other
+       failures return ``-EIO``.
diff --git a/drivers/net/ethernet/marvell/octeontx2/af/rvu_cgx.c b/drivers/net/ethernet/marvell/octeontx2/af/rvu_cgx.c
index 87d21889dc49e..7e09ca25101d4 100644
--- a/drivers/net/ethernet/marvell/octeontx2/af/rvu_cgx.c
+++ b/drivers/net/ethernet/marvell/octeontx2/af/rvu_cgx.c
@@ -649,7 +649,7 @@ int rvu_mbox_handler_cgx_stats_rst(struct rvu *rvu, struct msg_req *req,
 	 */
 	if (parent_pf->cgx_users > 1) {
 		dev_info(rvu->dev, "CGX busy, could not reset statistics\n");
-		return 0;
+		return -EBUSY;
 	}
 
 	rvu_get_cgx_lmac_id(rvu->pf2cgxlmac_map[pf], &cgx_idx, &lmac);
diff --git a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_devlink.c b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_devlink.c
index 4a5ce0e67dda8..daa8fb37f392c 100644
--- a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_devlink.c
+++ b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_devlink.c
@@ -125,10 +125,43 @@ static int otx2_dl_ucast_flt_cnt_validate(struct devlink *devlink, u32 id,
 	return 0;
 }
 
+static int otx2_dl_mac_stats_reset_get(struct devlink *devlink, u32 id,
+				       struct devlink_param_gset_ctx *ctx,
+				       struct netlink_ext_ack *extack)
+{
+	/* This is a one-shot trigger, so it has no state */
+	ctx->val.vbool = false;
+	return 0;
+}
+
+static int otx2_dl_mac_stats_reset_set(struct devlink *devlink, u32 id,
+				       struct devlink_param_gset_ctx *ctx,
+				       struct netlink_ext_ack *extack)
+{
+	struct otx2_devlink *otx2_dl = devlink_priv(devlink);
+	struct otx2_nic *pfvf = otx2_dl->pfvf;
+	int err;
+
+	if (!ctx->val.vbool)
+		return 0;
+
+	err = otx2_reset_mac_stats(pfvf);
+	if (err == -EBUSY) {
+		NL_SET_ERR_MSG_MOD(extack,
+				   "CGX port shared by multiple interfaces, cannot reset MAC stats");
+		return -EBUSY;
+	} else if (err) {
+		return -EIO;
+	}
+
+	return 0;
+}
+
 enum otx2_dl_param_id {
 	OTX2_DEVLINK_PARAM_ID_BASE = DEVLINK_PARAM_GENERIC_ID_MAX,
 	OTX2_DEVLINK_PARAM_ID_MCAM_COUNT,
 	OTX2_DEVLINK_PARAM_ID_UCAST_FLT_CNT,
+	OTX2_DEVLINK_PARAM_ID_MAC_STATS_RST,
 };
 
 static const struct devlink_param otx2_dl_params[] = {
@@ -142,6 +175,12 @@ static const struct devlink_param otx2_dl_params[] = {
 			     BIT(DEVLINK_PARAM_CMODE_RUNTIME),
 			     otx2_dl_ucast_flt_cnt_get, otx2_dl_ucast_flt_cnt_set,
 			     otx2_dl_ucast_flt_cnt_validate),
+	DEVLINK_PARAM_DRIVER(OTX2_DEVLINK_PARAM_ID_MAC_STATS_RST,
+			     "mac_stats_reset", DEVLINK_PARAM_TYPE_BOOL,
+			     BIT(DEVLINK_PARAM_CMODE_RUNTIME),
+			     otx2_dl_mac_stats_reset_get,
+			     otx2_dl_mac_stats_reset_set,
+			     NULL),
 };
 
 #ifdef CONFIG_RVU_ESWITCH

3/2 2026/08/14 11:37 llm patch-evaluator
1m Model: 
gemini-3.1-pro-preview

Args: 
null

Results: 
null

Tokens: 
							input: 3307
							output: 84
							thoughts: 530

Thoughts: 
**WorthFuzzing=false: Marvell OcteonTX2 Driver**

Okay, so I've got this patch that touches `drivers/net/ethernet/marvell/octeontx2/af/rvu_cgx.c` and `drivers/net/ethernet/marvell/octeontx2/nic/otx2_devlink.c`. It's adding a devlink parameter, `mac_stats_reset`, specifically for the Marvell OcteonTX2 driver. My first thought is, this is a vendor-specific hardware driver, and I need to determine if it's dependent on specific hardware not emulated in something like QEMU.

Given my experience, Marvell OcteonTX2 is definitely a hardware NIC, so it's likely not emulated. I'll need to confirm, but I'm thinking like the PCIe switch, SmartNIC, or GPU drivers I've worked with before (mlxsw, pds_core, qed, ionic, amdgpu, etc.), they typically require real hardware.

I was planning to `git grep` to find any clues about QEMU emulation. But, then I went back and re-read the prompt. It explicitly lists "vendor-specific PCIe switch, SmartNIC, or GPU drivers that require physical PCIe hardware cards not emulated in standard QEMU" as a reason to return `WorthFuzzing=false`. Bingo!

The Marvell OcteonTX2 (octeontx2) is *precisely* that: a vendor-specific hardware driver. I'm seeing changes in `drivers/net/ethernet/marvell/octeontx2/af/rvu_cgx.c` and `drivers/net/ethernet/marvell/octeontx2/nic/otx2_devlink.c`. It's all pointing to this driver.

Therefore, considering the prompt, I'm confident in setting `WorthFuzzing=false` here. It's a straightforward decision based on the nature of the driver and the prompt's explicit criteria.

4/2 2026/08/14 11:39 tool set-results
0m Args: 
{
  "EnableConfigs": [],
  "FocusSymbols": [],
  "Reasoning": "The patch modifies the Marvell OcteonTX2 driver, which is a vendor-specific hardware NIC driver. This hardware is not emulated in standard QEMU, so the code cannot be reached in virtualized environments like GCE or QEMU.",
  "WorthFuzzing": false
}

Results: 
{
  "EnableConfigs": null,
  "FocusSymbols": [],
  "Reasoning": "The patch modifies the Marvell OcteonTX2 driver, which is a vendor-specific hardware NIC driver. This hardware is not emulated in standard QEMU, so the code cannot be reached in virtualized environments like GCE or QEMU.",
  "WorthFuzzing": false
}
5/1 2026/08/14 11:39 action If
0m Args: 
{
  "WorthFuzzing": false
}

Results: 
null
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)