AI Trajectory

null

{
  "EnableConfigs": null,
  "FocusSymbols": [],
  "Reasoning": "The patch only removes dead code (unused functions atm_alloc_charge, atm_pcr_goal, sonet_copy_stats, and sonet_subtract_stats) and their corresponding declarations. There are no functional changes to reachable code.",
  "WorthFuzzing": false
}

null

{
  "PatchDiff": "commit ff87d59820c1c78a2ba232798326ff3262e693db\nAuthor: syz-cluster \u003ctriage@syzkaller.com\u003e\nDate:   Mon Jul 27 17:08:03 2026 +0000\n\n    syz-cluster: applied patch under review\n\ndiff --git a/MAINTAINERS b/MAINTAINERS\nindex 60cff00953dcbe..e7ebe79843cb13 100644\n--- a/MAINTAINERS\n+++ b/MAINTAINERS\n@@ -4279,7 +4279,6 @@ W:\thttp://linux-atm.sourceforge.net\n F:\tdrivers/atm/\n F:\tdrivers/usb/atm/\n F:\tinclude/linux/atm*\n-F:\tinclude/linux/sonet.h\n F:\tinclude/uapi/linux/atm*\n F:\tinclude/uapi/linux/sonet.h\n F:\tnet/atm/\ndiff --git a/include/linux/atmdev.h b/include/linux/atmdev.h\nindex fe21d2f547b5c2..92c2e20e741649 100644\n--- a/include/linux/atmdev.h\n+++ b/include/linux/atmdev.h\n@@ -229,9 +229,6 @@ static inline void atm_dev_put(struct atm_dev *dev)\n \n \n int atm_charge(struct atm_vcc *vcc,int truesize);\n-struct sk_buff *atm_alloc_charge(struct atm_vcc *vcc,int pdu_size,\n-    gfp_t gfp_flags);\n-int atm_pcr_goal(const struct atm_trafprm *tp);\n \n void vcc_release_async(struct atm_vcc *vcc, int reply);\n \ndiff --git a/include/linux/sonet.h b/include/linux/sonet.h\ndeleted file mode 100644\nindex 2b802b6d12ad18..00000000000000\n--- a/include/linux/sonet.h\n+++ /dev/null\n@@ -1,20 +0,0 @@\n-/* SPDX-License-Identifier: GPL-2.0 */\n-/* sonet.h - SONET/SHD physical layer control */\n-#ifndef LINUX_SONET_H\n-#define LINUX_SONET_H\n-\n-\n-#include \u003clinux/atomic.h\u003e\n-#include \u003cuapi/linux/sonet.h\u003e\n-\n-struct k_sonet_stats {\n-#define __HANDLE_ITEM(i) atomic_t i\n-\t__SONET_ITEMS\n-#undef __HANDLE_ITEM\n-};\n-\n-extern void sonet_copy_stats(struct k_sonet_stats *from,struct sonet_stats *to);\n-extern void sonet_subtract_stats(struct k_sonet_stats *from,\n-    struct sonet_stats *to);\n-\n-#endif\ndiff --git a/net/atm/atm_misc.c b/net/atm/atm_misc.c\nindex a30b83c1cb3fc8..c9d7609da18466 100644\n--- a/net/atm/atm_misc.c\n+++ b/net/atm/atm_misc.c\n@@ -7,7 +7,6 @@\n #include \u003clinux/atm.h\u003e\n #include \u003clinux/atmdev.h\u003e\n #include \u003clinux/skbuff.h\u003e\n-#include \u003clinux/sonet.h\u003e\n #include \u003clinux/bitops.h\u003e\n #include \u003clinux/errno.h\u003e\n #include \u003clinux/atomic.h\u003e\n@@ -22,81 +21,3 @@ int atm_charge(struct atm_vcc *vcc, int truesize)\n \treturn 0;\n }\n EXPORT_SYMBOL(atm_charge);\n-\n-struct sk_buff *atm_alloc_charge(struct atm_vcc *vcc, int pdu_size,\n-\t\t\t\t gfp_t gfp_flags)\n-{\n-\tstruct sock *sk = sk_atm(vcc);\n-\tint guess = SKB_TRUESIZE(pdu_size);\n-\n-\tatm_force_charge(vcc, guess);\n-\tif (atomic_read(\u0026sk-\u003esk_rmem_alloc) \u003c= sk-\u003esk_rcvbuf) {\n-\t\tstruct sk_buff *skb = alloc_skb(pdu_size, gfp_flags);\n-\n-\t\tif (skb) {\n-\t\t\tatomic_add(skb-\u003etruesize-guess,\n-\t\t\t\t   \u0026sk-\u003esk_rmem_alloc);\n-\t\t\treturn skb;\n-\t\t}\n-\t}\n-\tatm_return(vcc, guess);\n-\tatomic_inc(\u0026vcc-\u003estats-\u003erx_drop);\n-\treturn NULL;\n-}\n-EXPORT_SYMBOL(atm_alloc_charge);\n-\n-\n-/*\n- * atm_pcr_goal returns the positive PCR if it should be rounded up, the\n- * negative PCR if it should be rounded down, and zero if the maximum available\n- * bandwidth should be used.\n- *\n- * The rules are as follows (* = maximum, - = absent (0), x = value \"x\",\n- * (x+ = x or next value above x, x- = x or next value below):\n- *\n- *\tmin max pcr\tresult\t\tmin max pcr\tresult\n- *\t-   -   -\t* (UBR only)\tx   -   -\tx+\n- *\t-   -   *\t*\t\tx   -   *\t*\n- *\t-   -   z\tz-\t\tx   -   z\tz-\n- *\t-   *   -\t*\t\tx   *   -\tx+\n- *\t-   *   *\t*\t\tx   *   *\t*\n- *\t-   *   z\tz-\t\tx   *   z\tz-\n- *\t-   y   -\ty-\t\tx   y   -\tx+\n- *\t-   y   *\ty-\t\tx   y   *\ty-\n- *\t-   y   z\tz-\t\tx   y   z\tz-\n- *\n- * All non-error cases can be converted with the following simple set of rules:\n- *\n- *   if pcr == z then z-\n- *   else if min == x \u0026\u0026 pcr == - then x+\n- *     else if max == y then y-\n- *\t else *\n- */\n-\n-int atm_pcr_goal(const struct atm_trafprm *tp)\n-{\n-\tif (tp-\u003epcr \u0026\u0026 tp-\u003epcr != ATM_MAX_PCR)\n-\t\treturn -tp-\u003epcr;\n-\tif (tp-\u003emin_pcr \u0026\u0026 !tp-\u003epcr)\n-\t\treturn tp-\u003emin_pcr;\n-\tif (tp-\u003emax_pcr != ATM_MAX_PCR)\n-\t\treturn -tp-\u003emax_pcr;\n-\treturn 0;\n-}\n-EXPORT_SYMBOL(atm_pcr_goal);\n-\n-void sonet_copy_stats(struct k_sonet_stats *from, struct sonet_stats *to)\n-{\n-#define __HANDLE_ITEM(i) to-\u003ei = atomic_read(\u0026from-\u003ei)\n-\t__SONET_ITEMS\n-#undef __HANDLE_ITEM\n-}\n-EXPORT_SYMBOL(sonet_copy_stats);\n-\n-void sonet_subtract_stats(struct k_sonet_stats *from, struct sonet_stats *to)\n-{\n-#define __HANDLE_ITEM(i) atomic_sub(to-\u003ei, \u0026from-\u003ei)\n-\t__SONET_ITEMS\n-#undef __HANDLE_ITEM\n-}\n-EXPORT_SYMBOL(sonet_subtract_stats);\n"
}

best-expensive

null

{
  "EnableConfigs": null,
  "FocusSymbols": [],
  "Reasoning": "The patch only removes dead code (unused functions atm_alloc_charge, atm_pcr_goal, sonet_copy_stats, and sonet_subtract_stats) and their corresponding declarations. There are no functional changes to reachable code.",
  "WorthFuzzing": false
}

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.

For your convenience, here is the diff of the changes:
commit ff87d59820c1c78a2ba232798326ff3262e693db
Author: syz-cluster <triage@syzkaller.com>
Date:   Mon Jul 27 17:08:03 2026 +0000

    syz-cluster: applied patch under review

diff --git a/MAINTAINERS b/MAINTAINERS
index 60cff00953dcbe..e7ebe79843cb13 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -4279,7 +4279,6 @@ W:	http://linux-atm.sourceforge.net
 F:	drivers/atm/
 F:	drivers/usb/atm/
 F:	include/linux/atm*
-F:	include/linux/sonet.h
 F:	include/uapi/linux/atm*
 F:	include/uapi/linux/sonet.h
 F:	net/atm/
diff --git a/include/linux/atmdev.h b/include/linux/atmdev.h
index fe21d2f547b5c2..92c2e20e741649 100644
--- a/include/linux/atmdev.h
+++ b/include/linux/atmdev.h
@@ -229,9 +229,6 @@ static inline void atm_dev_put(struct atm_dev *dev)
 
 
 int atm_charge(struct atm_vcc *vcc,int truesize);
-struct sk_buff *atm_alloc_charge(struct atm_vcc *vcc,int pdu_size,
-    gfp_t gfp_flags);
-int atm_pcr_goal(const struct atm_trafprm *tp);
 
 void vcc_release_async(struct atm_vcc *vcc, int reply);
 
diff --git a/include/linux/sonet.h b/include/linux/sonet.h
deleted file mode 100644
index 2b802b6d12ad18..00000000000000
--- a/include/linux/sonet.h
+++ /dev/null
@@ -1,20 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-/* sonet.h - SONET/SHD physical layer control */
-#ifndef LINUX_SONET_H
-#define LINUX_SONET_H
-
-
-#include <linux/atomic.h>
-#include <uapi/linux/sonet.h>
-
-struct k_sonet_stats {
-#define __HANDLE_ITEM(i) atomic_t i
-	__SONET_ITEMS
-#undef __HANDLE_ITEM
-};
-
-extern void sonet_copy_stats(struct k_sonet_stats *from,struct sonet_stats *to);
-extern void sonet_subtract_stats(struct k_sonet_stats *from,
-    struct sonet_stats *to);
-
-#endif
diff --git a/net/atm/atm_misc.c b/net/atm/atm_misc.c
index a30b83c1cb3fc8..c9d7609da18466 100644
--- a/net/atm/atm_misc.c
+++ b/net/atm/atm_misc.c
@@ -7,7 +7,6 @@
 #include <linux/atm.h>
 #include <linux/atmdev.h>
 #include <linux/skbuff.h>
-#include <linux/sonet.h>
 #include <linux/bitops.h>
 #include <linux/errno.h>
 #include <linux/atomic.h>
@@ -22,81 +21,3 @@ int atm_charge(struct atm_vcc *vcc, int truesize)
 	return 0;
 }
 EXPORT_SYMBOL(atm_charge);
-
-struct sk_buff *atm_alloc_charge(struct atm_vcc *vcc, int pdu_size,
-				 gfp_t gfp_flags)
-{
-	struct sock *sk = sk_atm(vcc);
-	int guess = SKB_TRUESIZE(pdu_size);
-
-	atm_force_charge(vcc, guess);
-	if (atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf) {
-		struct sk_buff *skb = alloc_skb(pdu_size, gfp_flags);
-
-		if (skb) {
-			atomic_add(skb->truesize-guess,
-				   &sk->sk_rmem_alloc);
-			return skb;
-		}
-	}
-	atm_return(vcc, guess);
-	atomic_inc(&vcc->stats->rx_drop);
-	return NULL;
-}
-EXPORT_SYMBOL(atm_alloc_charge);
-
-
-/*
- * atm_pcr_goal returns the positive PCR if it should be rounded up, the
- * negative PCR if it should be rounded down, and zero if the maximum available
- * bandwidth should be used.
- *
- * The rules are as follows (* = maximum, - = absent (0), x = value "x",
- * (x+ = x or next value above x, x- = x or next value below):
- *
- *	min max pcr	result		min max pcr	result
- *	-   -   -	* (UBR only)	x   -   -	x+
- *	-   -   *	*		x   -   *	*
- *	-   -   z	z-		x   -   z	z-
- *	-   *   -	*		x   *   -	x+
- *	-   *   *	*		x   *   *	*
- *	-   *   z	z-		x   *   z	z-
- *	-   y   -	y-		x   y   -	x+
- *	-   y   *	y-		x   y   *	y-
- *	-   y   z	z-		x   y   z	z-
- *
- * All non-error cases can be converted with the following simple set of rules:
- *
- *   if pcr == z then z-
- *   else if min == x && pcr == - then x+
- *     else if max == y then y-
- *	 else *
- */
-
-int atm_pcr_goal(const struct atm_trafprm *tp)
-{
-	if (tp->pcr && tp->pcr != ATM_MAX_PCR)
-		return -tp->pcr;
-	if (tp->min_pcr && !tp->pcr)
-		return tp->min_pcr;
-	if (tp->max_pcr != ATM_MAX_PCR)
-		return -tp->max_pcr;
-	return 0;
-}
-EXPORT_SYMBOL(atm_pcr_goal);
-
-void sonet_copy_stats(struct k_sonet_stats *from, struct sonet_stats *to)
-{
-#define __HANDLE_ITEM(i) to->i = atomic_read(&from->i)
-	__SONET_ITEMS
-#undef __HANDLE_ITEM
-}
-EXPORT_SYMBOL(sonet_copy_stats);
-
-void sonet_subtract_stats(struct k_sonet_stats *from, struct sonet_stats *to)
-{
-#define __HANDLE_ITEM(i) atomic_sub(to->i, &from->i)
-	__SONET_ITEMS
-#undef __HANDLE_ITEM
-}
-EXPORT_SYMBOL(sonet_subtract_stats);

gemini-3.1-pro-preview

null

null

							input: 3690
							output: 19
							thoughts: 203
						

**Unused Code Removal in ATM Subsystem**

Okay, so this patch is cleaning up some dead code within the ATM subsystem. Specifically, it's getting rid of `atm_alloc_charge`, `atm_pcr_goal`, `sonet_copy_stats`, and `sonet_subtract_stats` functions from `net/atm/atm_misc.c`.  It's also removing their corresponding declarations from `include/linux/atmdev.h` and `include/linux/sonet.h`, and, importantly, deleting `include/linux/sonet.h` entirely. Essentially, this looks like a straightforward removal of unused functionality.

My initial thought is that this is a low-impact change. Because it's only *removing* code and doesn't introduce any new functionality or modify existing executable paths, I wouldn't expect it to be a candidate for fuzzing. No need to waste resources.

However, let's be absolutely certain these functions *are* unused. Better safe than sorry, especially with ATM code. I'm going to run a quick `grepper` search for those function names – `atm_alloc_charge`, `atm_pcr_goal`, `sonet_copy_stats`, and `sonet_subtract_stats` – just to confirm that they aren't, in fact, called anywhere else in the kernel source. Gotta be thorough.

no matches

{
  "Expression": "atm_alloc_charge"
}

{
  "error": "no matches"
}

gemini-3.1-pro-preview

null

null

							input: 4225
							output: 20
							thoughts: 12
						

Okay, here's my interpretation of that thought process, tailored for an expert audience, and written in the first person:

**Initial Assessment: Checking `atm_pcr_goal`**

Right, let's take a quick look at `atm_pcr_goal`. This suggests we're likely dealing with an automated testing or monitoring context, potentially related to PCR (Polymerase Chain Reaction) applications. The term `atm` implies automation, so I need to understand what this specific goal is. Is it a target value for a specific assay, a success rate, or a specific threshold for some PCR-related metric? The context is key here. I'll need to immediately figure out if this goal is consistent with known best practices, previous performance data, or regulatory requirements. Understanding the data type of `atm_pcr_goal` is also critical – a simple integer, a range, a percentage, or something more complex? My first task is going to be to find out the nature of that goal and how it interacts with other system parameters.

no matches

{
  "Expression": "atm_pcr_goal"
}

{
  "error": "no matches"
}

gemini-3.1-pro-preview

null

null

							input: 4491
							output: 20
							thoughts: 12
						

Okay, here's my take on those thoughts, tailored for an expert audience, presented in the first person:

**Sonet Copy Stats Check**

Alright, time to get into it. Let's see... the first thing I'm thinking is, "Let's check `sonet_copy_stats`." Given my understanding of the system architecture, I'm likely wanting to examine this function or data structure. The context will tell me what I expect to find. Are we looking at performance metrics, error counts, resource usage – perhaps a granular breakdown of data transfer activity within a SONET network? Whatever the specifics are, I'm trying to quickly ascertain the status or behavior of data copying, probably in relation to SONET protocols. I'm already anticipating the nuances of the underlying implementation, keeping in mind potential bottlenecks or areas of concern I've encountered in similar scenarios. My initial scan will be guided by the typical performance indicators I'm accustomed to.

no matches

{
  "Expression": "sonet_copy_stats"
}

{
  "error": "no matches"
}

gemini-3.1-pro-preview

null

null

							input: 4739
							output: 20
							thoughts: 12
						

Okay, here's my take on those thoughts, tailored for an expert audience, and delivered as a first-person summary:

**Initial Check on `sonet_subtract_stats`**

Alright, time to dive in. My initial thought is to zero in on `sonet_subtract_stats`. It's likely a key component in whatever I'm analyzing, and understanding its function is paramount. My expectation, given the name, is that this probably deals with some form of subtraction or differencing related to SONET (Synchronous Optical Network) performance metrics, or perhaps statistical analysis related to changes. The 'stats' part immediately flags potential areas: are we looking at averages, standard deviations, deltas, or perhaps a more complex statistical model derived from the subtraction of SONET data? Without more context, I have to assume its functionality and move forward. I'm going to start by confirming my expectations.

no matches

{
  "Expression": "sonet_subtract_stats"
}

{
  "error": "no matches"
}

gemini-3.1-pro-preview

null

null

							input: 4975
							output: 82
							thoughts: 28
						

Okay, here's my take on those thoughts, framed as my own reasoning:

**Dead Code Deletion Reasoning**

Alright, I'm looking at this patch and it's clear: nothing here is actually *being* used. Pure dead code removal. Given that context, it's a straightforward conclusion. There's no functional change, no new logic, no new execution paths. Therefore, from a fuzzing perspective, this isn't going to uncover anything new. This code removal is not something we want to expend our fuzzing effort on. The `WorthFuzzing` flag? It should absolutely be `false`. No debate. It's a waste of resources to run fuzzing on this set of changes.

{
  "EnableConfigs": [],
  "FocusSymbols": [],
  "Reasoning": "The patch only removes dead code (unused functions atm_alloc_charge, atm_pcr_goal, sonet_copy_stats, and sonet_subtract_stats) and their corresponding declarations. There are no functional changes to reachable code.",
  "WorthFuzzing": false
}

{
  "EnableConfigs": null,
  "FocusSymbols": [],
  "Reasoning": "The patch only removes dead code (unused functions atm_alloc_charge, atm_pcr_goal, sonet_copy_stats, and sonet_subtract_stats) and their corresponding declarations. There are no functional changes to reachable code.",
  "WorthFuzzing": false
}