INFO: rcu detected stall in inotify_add

ID	Workflow	Result	Correct	Bug	Created	Started	Finished	Revision	Error
e045a4ed-80f6-4c10-85e6-2c53c68ad305	assessment-security	DenialOfService: ✅ Exploitable: ❌ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ❌ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ❌ VMGuestTrigger: ❌ VMHostTrigger: ❌	❓	INFO: rcu detected stall in inotify_add_watch	2026/05/23 23:35	2026/05/23 23:35	2026/05/24 00:20	c69befb30ac10e158cc9d1557b508ee3f0eca1de

Title	Replies (including bot)	Last reply
[syzbot] [modules?] INFO: rcu detected stall in inotify_add_watch	0 (1)	2026/01/19 19:56

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Last reply

[syzbot] [modules?] INFO: rcu detected stall in inotify_add_watch

0 (1)

2026/01/19 19:56

Kernel	Title	Rank 🛈	Count	Last	Reported	Patched	Status
linux-5.15	INFO: rcu detected stall in inotify_add_watch	1	2	260d	279d	0/3	auto-obsoleted due to no activity on 2026/01/07 19:37
upstream	INFO: rcu detected stall in sys_inotify_add_watch (3) fs	1	2	491d	564d	0/29	auto-obsoleted due to no activity on 2025/05/12 13:24
linux-5.15	INFO: rcu detected stall in sys_inotify_add_watch	1	1	507d	507d	0/3	auto-obsoleted due to no activity on 2025/05/05 23:52
upstream	INFO: rcu detected stall in sys_inotify_add_watch (2) lsm	1	1	679d	679d	0/29	auto-obsoleted due to no activity on 2024/11/04 18:18
upstream	INFO: rcu detected stall in sys_inotify_add_watch fs	1	1	1734d	1734d	0/29	auto-closed as invalid on 2021/12/16 04:51

Rank 🛈

linux-5.15

INFO: rcu detected stall in inotify_add_watch

260d

279d

0/3

auto-obsoleted due to no activity on 2026/01/07 19:37

upstream

INFO: rcu detected stall in sys_inotify_add_watch (3) fs

491d

564d

0/29

auto-obsoleted due to no activity on 2025/05/12 13:24

linux-5.15

INFO: rcu detected stall in sys_inotify_add_watch

507d

0/3

auto-obsoleted due to no activity on 2025/05/05 23:52

upstream

INFO: rcu detected stall in sys_inotify_add_watch (2) lsm

679d

0/29

auto-obsoleted due to no activity on 2024/11/04 18:18

upstream

INFO: rcu detected stall in sys_inotify_add_watch fs

1734d

0/29

auto-closed as invalid on 2021/12/16 04:51

Created	Duration	User	Repo	Result
2026/05/25 22:28	32m	retest repro	upstream	log
2026/05/25 22:15	25m	retest repro	upstream	log
2026/01/29 22:50	21m	retest repro	upstream	report log

Created

Duration

User

Patch

Repo

Result

2026/05/25 22:28

32m

retest repro

upstream

log

2026/05/25 22:15

25m

retest repro

upstream

log

2026/01/29 22:50

21m

retest repro

upstream

report log

rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P12/2:b..l P6218/1:b..l P5834/1:b..l rcu: (detected by 1, t=10503 jiffies, g=14653, q=1024 ncpus=2) task:udevd state:R running task stack:24568 pid:5834 tgid:5834 ppid:5196 task_flags:0x440140 flags:0x00080000 Call Trace: <TASK> context_switch kernel/sched/core.c:5256 [inline] __schedule+0x149b/0x4fd0 kernel/sched/core.c:6863 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7190 irqentry_exit+0x5e3/0x670 kernel/entry/common.c:216 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:rcu_read_lock include/linux/rcupdate.h:868 [inline] RIP: 0010:class_rcu_constructor include/linux/rcupdate.h:1195 [inline] RIP: 0010:is_module_text_address+0x44/0x1e0 kernel/module/main.c:3856 Code: 00 00 00 48 c7 c7 a0 1a f4 8d 31 f6 31 d2 b9 02 00 00 00 45 31 c0 45 31 c9 53 e8 77 82 f2 ff 48 83 c4 08 e8 4e 5a ae 09 85 c0 <74> 3a e8 85 91 fb ff 84 c0 75 31 e8 3c 5a ae 09 85 c0 74 28 80 3d RSP: 0018:ffffc90002ff7920 EFLAGS: 00000202 RAX: 0000000000000001 RBX: ffffffff81ab6c1d RCX: ffff88807bec3d00 RDX: 00000000706f5022 RSI: ffffffff8d976a6b RDI: ffffffff8bc086e0 RBP: 0000000000000001 R08: ffffffff81ab6c1d R09: ffffffff8df41aa0 R10: dffffc0000000000 R11: ffffffff81acf4d0 R12: ffff88807bec3d00 R13: ffff88805500bc80 R14: 00007f1b687219a7 R15: 1ffff920005fef3e kernel_text_address+0x94/0xe0 kernel/extable.c:119 __kernel_text_address+0xd/0x40 kernel/extable.c:79 unwind_get_return_address+0x4d/0x90 arch/x86/kernel/unwind_orc.c:385 arch_stack_walk+0xfc/0x150 arch/x86/kernel/stacktrace.c:26 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 unpoison_slab_object mm/kasan/common.c:340 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:366 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4953 [inline] slab_alloc_node mm/slub.c:5263 [inline] kmem_cache_alloc_noprof+0x37d/0x710 mm/slub.c:5270 inotify_new_watch fs/notify/inotify/inotify_user.c:599 [inline] inotify_update_watch fs/notify/inotify/inotify_user.c:647 [inline] __do_sys_inotify_add_watch fs/notify/inotify/inotify_user.c:781 [inline] __se_sys_inotify_add_watch+0x6d4/0xf10 fs/notify/inotify/inotify_user.c:729 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f1b687219a7 RSP: 002b:00007fffd4df20d8 EFLAGS: 00000206 ORIG_RAX: 00000000000000fe RAX: ffffffffffffffda RBX: 0000558f453876d0 RCX: 00007f1b687219a7 RDX: 0000000000000008 RSI: 0000558f45371360 RDI: 0000000000000007 RBP: 0000558f45360910 R08: 00000000000001d0 R09: 0000000000000003 R10: 0000000000000000 R11: 0000000000000206 R12: 0000558f453876d0 R13: 0000558f4536e190 R14: 0000000000000008 R15: 0000558f453876d0 </TASK> task:kworker/u8:17 state:R running task stack:24568 pid:6218 tgid:6218 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: events_unbound cfg80211_wiphy_work Call Trace: <TASK> context_switch kernel/sched/core.c:5256 [inline] __schedule+0x149b/0x4fd0 kernel/sched/core.c:6863 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7190 irqentry_exit+0x5e3/0x670 kernel/entry/common.c:216 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_release+0x2d8/0x3b0 kernel/locking/lockdep.c:5893 Code: 33 e2 10 00 00 00 00 eb b5 e8 d4 9e bb 09 f7 c3 00 02 00 00 74 b9 65 48 8b 05 c4 ed e1 10 48 3b 44 24 28 75 44 fb 48 83 c4 30 <5b> 41 5c 41 5d 41 5e 41 5f 5d e9 94 1e 72 ff cc 48 8d 3d 71 4a e7 RSP: 0018:ffffc9000257f3e0 EFLAGS: 00000282 RAX: 0526f4b768dc6600 RBX: 0000000000000202 RCX: 0000000000000046 RDX: 0000000000000003 RSI: ffffffff8d976a6b RDI: ffffffff8bc086e0 RBP: ffff88802d8e2a28 R08: ffffc9000257fa20 R09: ffffc9000257f538 R10: dffffc0000000000 R11: fffff520004afea9 R12: 0000000000000003 R13: 0000000000000003 R14: ffffffff8df41aa0 R15: ffff88802d8e1e80 rcu_lock_release include/linux/rcupdate.h:341 [inline] rcu_read_unlock include/linux/rcupdate.h:897 [inline] class_rcu_destructor include/linux/rcupdate.h:1195 [inline] unwind_next_frame+0x1ab1/0x23d0 arch/x86/kernel/unwind_orc.c:695 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2540 [inline] slab_free mm/slub.c:6670 [inline] kmem_cache_free+0x197/0x620 mm/slub.c:6781 skb_release_data+0x62d/0x7c0 net/core/skbuff.c:1107 skb_release_all net/core/skbuff.c:1182 [inline] __kfree_skb net/core/skbuff.c:1196 [inline] sk_skb_reason_drop+0x127/0x170 net/core/skbuff.c:1234 kfree_skb_reason include/linux/skbuff.h:1322 [inline] kfree_skb include/linux/skbuff.h:1331 [inline] ieee80211_iface_work+0xb2a/0x12d0 net/mac80211/iface.c:1792 cfg80211_wiphy_work+0x2ab/0x450 net/wireless/core.c:438 process_one_work kernel/workqueue.c:3257 [inline] process_scheduled_works+0xad1/0x1770 kernel/workqueue.c:3340 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3421 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 </TASK> task:kworker/u8:0 state:R running task stack:24480 pid:12 tgid:12 ppid:2 task_flags:0x4208160 flags:0x00080000 Workqueue: ipv6_addrconf addrconf_dad_work Call Trace: <TASK> context_switch kernel/sched/core.c:5256 [inline] __schedule+0x149b/0x4fd0 kernel/sched/core.c:6863 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7190 irqentry_exit+0x5e3/0x670 kernel/entry/common.c:216 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:lock_release+0x2d8/0x3b0 kernel/locking/lockdep.c:5893 Code: 33 e2 10 00 00 00 00 eb b5 e8 d4 9e bb 09 f7 c3 00 02 00 00 74 b9 65 48 8b 05 c4 ed e1 10 48 3b 44 24 28 75 44 fb 48 83 c4 30 <5b> 41 5c 41 5d 41 5e 41 5f 5d e9 94 1e 72 ff cc 48 8d 3d 71 4a e7 RSP: 0018:ffffc90000116f20 EFLAGS: 00000282 RAX: ccca9c3ae3660b00 RBX: 0000000000000202 RCX: 0000000000000046 RDX: 0000000000000005 RSI: ffffffff8d976a6b RDI: ffffffff8bc086e0 RBP: ffff88801c2a6778 R08: ffffc900001175b8 R09: ffffc90000117078 R10: dffffc0000000000 R11: fffff52000022e11 R12: 0000000000000005 R13: 0000000000000005 R14: ffffffff8df41aa0 R15: ffff88801c2a5b80 rcu_lock_release include/linux/rcupdate.h:341 [inline] rcu_read_unlock include/linux/rcupdate.h:897 [inline] class_rcu_destructor include/linux/rcupdate.h:1195 [inline] unwind_next_frame+0x1ab1/0x23d0 arch/x86/kernel/unwind_orc.c:695 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415 kasan_kmalloc include/linux/kasan.h:263 [inline] __kmalloc_cache_noprof+0x3e2/0x700 mm/slub.c:5776 kmalloc_noprof include/linux/slab.h:957 [inline] kzalloc_noprof include/linux/slab.h:1094 [inline] ref_tracker_alloc+0x133/0x460 lib/ref_tracker.c:271 __netdev_tracker_alloc include/linux/netdevice.h:4400 [inline] netdev_hold include/linux/netdevice.h:4429 [inline] dst_init+0xd9/0x450 net/core/dst.c:52 dst_alloc+0x12a/0x170 net/core/dst.c:93 ip6_dst_alloc net/ipv6/route.c:342 [inline] icmp6_dst_alloc+0x75/0x420 net/ipv6/route.c:3333 mld_sendpack+0x683/0xe60 net/ipv6/mcast.c:1844 ipv6_mc_dad_complete+0x88/0x410 net/ipv6/mcast.c:2279 addrconf_dad_completed+0x6d5/0xd60 net/ipv6/addrconf.c:4340 addrconf_dad_work+0xc36/0x14b0 net/ipv6/addrconf.c:-1 process_one_work kernel/workqueue.c:3257 [inline] process_scheduled_works+0xad1/0x1770 kernel/workqueue.c:3340 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3421 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 </TASK> rcu: rcu_preempt kthread starved for 10628 jiffies! g14653 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1 rcu: Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior. rcu: RCU grace-period kthread stack dump: task:rcu_preempt state:R running task stack:27480 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: <TASK> context_switch kernel/sched/core.c:5256 [inline] __schedule+0x149b/0x4fd0 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] schedule+0x165/0x360 kernel/sched/core.c:6960 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 </TASK> rcu: Stack dump where RCU GP kthread last ran: CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82 Code: 1e 84 b6 f5 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 53 91 0e 00 f3 0f 1e fa fb f4 <e9> f3 83 b6 f5 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffc90000197e20 EFLAGS: 000002c6 RAX: 00000000000f3f43 RBX: ffffffff8197149e RCX: 0000000080000001 RDX: 0000000000000001 RSI: ffffffff8d792d31 RDI: ffffffff8bc086e0 RBP: ffffc90000197f10 R08: ffff8880b87336db R09: 1ffff110170e66db R10: dffffc0000000000 R11: ffffed10170e66dc R12: ffffffff8f822470 R13: 1ffff1100385fb70 R14: 0000000000000001 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff888125f1f000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fe5546e0f98 CR3: 000000002efbb000 CR4: 0000000000350ef0 Call Trace: <TASK> arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline] default_idle+0x13/0x20 arch/x86/kernel/process.c:767 default_idle_call+0x73/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:191 [inline] do_idle+0x1be/0x4d0 kernel/sched/idle.c:332 cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:430 start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:312 common_startup_64+0x13e/0x147 </TASK>

Crashes (2):
Time	Kernel	Commit	Syzkaller	Config	Log	Report	Syz repro	C repro	VM info	Assets (help?)	Manager	Title
2026/01/15 19:54	upstream	944aacb68baf	d6526ea3	.config	console log	report	syz / log			[disk image] [vmlinux] [kernel image]	ci-upstream-kasan-gce-root	INFO: rcu detected stall in inotify_add_watch
2026/02/14 14:59	upstream	c22e26bd0906	1e62d198	.config	console log	report			info	[disk image] [vmlinux] [kernel image]	ci-upstream-kasan-gce-smack-root	INFO: rcu detected stall in inotify_add_watch

Crashes (2):

Assets (help?)