INFO: rcu detected stall in devtmpfsd (3)

ID	Workflow	Result	Correct	Bug	Created	Started	Finished	Revision	Error
3363d187-6122-4244-b344-cfec50c2d3e3	assessment-security	DenialOfService: ❌ Exploitable: ❌ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ❌ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ❌ VMGuestTrigger: ❌ VMHostTrigger: ❌	❓	INFO: rcu detected stall in devtmpfsd (3)	2026/05/31 02:16	2026/05/31 02:16	2026/05/31 03:21	6b4a844333e83556da95d61d7f207e7ef5cd4bc6
e169da74-29b2-43de-8c80-a97c49155552	assessment-security		💥	INFO: rcu detected stall in devtmpfsd (3)	2026/05/14 13:39	2026/05/14 13:39	2026/05/14 13:40	6ccb967e465e832a7bfd7a116ad00d52a0923a5d	failed to run ["git" "pull" "origin" "HEAD" "--depth=1" "--allow-unrelated-histories"]: exit status 128 From /app/workdir/repo/linux * branch HEAD -> FETCH_HEAD Updating files: ... truncated to first 200 bytes; open job for full error

Title	Replies (including bot)	Last reply
[syzbot] [mm?] [input?] [usb?] INFO: rcu detected stall in devtmpfsd (3)	2 (5)	2025/07/21 08:54

Title

Replies (including bot)

Last reply

[syzbot] [mm?] [input?] [usb?] INFO: rcu detected stall in devtmpfsd (3)

2 (5)

2025/07/21 08:54

Kernel	Title	Rank 🛈	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
upstream	INFO: rcu detected stall in devtmpfsd mm lsm fs	1				4	937d	1015d	0/29	auto-obsoleted due to no activity on 2024/02/25 21:47
upstream	INFO: rcu detected stall in devtmpfsd (2) mm	1				16	520d	701d	0/29	auto-obsoleted due to no activity on 2025/04/18 16:52

Rank 🛈

upstream

INFO: rcu detected stall in devtmpfsd mm lsm fs

937d

1015d

0/29

auto-obsoleted due to no activity on 2024/02/25 21:47

upstream

INFO: rcu detected stall in devtmpfsd (2) mm

520d

701d

0/29

auto-obsoleted due to no activity on 2025/04/18 16:52

Created	Duration	User	Patch	Repo	Result
2026/06/21 14:18	56m	retest repro		linux-next	error
2026/06/03 05:07	25m	retest repro		upstream	log
2026/03/25 00:18	35m	retest repro		upstream	report log
2026/03/24 23:48	37m	retest repro		upstream	report log
2026/01/13 22:04	29m	retest repro		upstream	report log
2025/07/21 07:38	1h15m	hdanton@sina.com	patch	upstream	report log
2025/07/21 02:31	21m	hdanton@sina.com		upstream	report log

Created

Duration

User

Patch

Repo

Result

2026/06/21 14:18

56m

retest repro

linux-next

error

2026/06/03 05:07

25m

retest repro

upstream

log

2026/03/25 00:18

35m

retest repro

upstream

report log

2026/03/24 23:48

37m

retest repro

upstream

report log

2026/01/13 22:04

29m

retest repro

upstream

report log

2025/07/21 07:38

1h15m

hdanton@sina.com

patch

upstream

report log

2025/07/21 02:31

21m

hdanton@sina.com

upstream

report log

Created	Duration	User	Repo	Result
2025/11/04 18:16	2h56m	bisect fix	upstream	OK (0) job log
2025/09/24 02:19	4h44m	bisect fix	upstream	OK (0) job log log
2025/08/15 19:41	5h47m	bisect fix	upstream	OK (0) job log log

Created

Duration

User

Patch

Repo

Result

2025/11/04 18:16

2h56m

bisect fix

upstream

OK (0) job log

2025/09/24 02:19

4h44m

bisect fix

upstream

OK (0) job log log

2025/08/15 19:41

5h47m

bisect fix

upstream

OK (0) job log log

rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P26/1:b.el P3584/2:b..l rcu: (detected by 0, t=10502 jiffies, g=13645, q=1327 ncpus=2) task:kworker/1:2 state:R running task stack:19608 pid:3584 tgid:3584 ppid:2 task_flags:0x4208060 flags:0x00004000 Workqueue: mld mld_dad_work Call Trace: <TASK> context_switch kernel/sched/core.c:5397 [inline] __schedule+0x16f5/0x4d00 kernel/sched/core.c:6786 preempt_schedule_notrace+0xd1/0x110 kernel/sched/core.c:7059 preempt_schedule_notrace_thunk+0x16/0x30 arch/x86/entry/thunk.S:13 rcu_is_watching+0x7f/0xb0 kernel/rcu/tree.c:746 trace_lock_release include/trace/events/lock.h:69 [inline] lock_release+0x4b/0x3e0 kernel/locking/lockdep.c:5882 rcu_lock_release include/linux/rcupdate.h:341 [inline] rcu_read_unlock include/linux/rcupdate.h:871 [inline] class_rcu_destructor include/linux/rcupdate.h:1155 [inline] unwind_next_frame+0x19a9/0x2390 arch/x86/kernel/unwind_orc.c:680 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:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:319 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:345 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4148 [inline] slab_alloc_node mm/slub.c:4197 [inline] kmem_cache_alloc_noprof+0x1c1/0x3c0 mm/slub.c:4204 dst_alloc+0x105/0x170 net/core/dst.c:89 ip6_dst_alloc net/ipv6/route.c:342 [inline] icmp6_dst_alloc+0x75/0x420 net/ipv6/route.c:3324 mld_sendpack+0x678/0xd80 net/ipv6/mcast.c:1857 mld_dad_work+0x45/0x520 net/ipv6/mcast.c:2308 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 </TASK> task:kdevtmpfs state:R running task stack:26216 pid:26 tgid:26 ppid:2 task_flags:0x208140 flags:0x00004000 Call Trace: <TASK> context_switch kernel/sched/core.c:5397 [inline] __schedule+0x16f5/0x4d00 kernel/sched/core.c:6786 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7109 irqentry_exit+0x6f/0x90 kernel/entry/common.c:307 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_acquire+0x175/0x360 kernel/locking/lockdep.c:5875 Code: 00 00 00 00 9c 8f 44 24 30 f7 44 24 30 00 02 00 00 0f 85 cd 00 00 00 f7 44 24 08 00 02 00 00 74 01 fb 65 48 8b 05 9b 13 02 11 <48> 3b 44 24 58 0f 85 f2 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e RSP: 0018:ffffc90000a173b8 EFLAGS: 00000206 RAX: 520cf176917d9000 RBX: 0000000000000000 RCX: 520cf176917d9000 RDX: 0000000000000000 RSI: ffffffff8db869c3 RDI: ffffffff8be29d80 RBP: ffffffff8172aae5 R08: 0000000000000000 R09: ffffffff8172aae5 R10: ffffc90000a17578 R11: ffffffff81ad00a0 R12: 0000000000000002 R13: ffffffff8e13f0e0 R14: 0000000000000000 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:841 [inline] class_rcu_constructor include/linux/rcupdate.h:1155 [inline] unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 save_stack+0xf5/0x1f0 mm/page_owner.c:156 __reset_page_owner+0x71/0x1f0 mm/page_owner.c:308 reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1248 [inline] __free_frozen_pages+0xc71/0xe70 mm/page_alloc.c:2706 __slab_free+0x326/0x400 mm/slub.c:4554 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x97/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4148 [inline] slab_alloc_node mm/slub.c:4197 [inline] __do_kmalloc_node mm/slub.c:4327 [inline] __kmalloc_noprof+0x224/0x4f0 mm/slub.c:4340 kmalloc_noprof include/linux/slab.h:909 [inline] kmalloc_array_noprof include/linux/slab.h:948 [inline] security_inode_init_security+0x107/0x3f0 security/security.c:1829 shmem_mknod+0x1f6/0x3e0 mm/shmem.c:3851 vfs_mknod+0x37f/0x3c0 fs/namei.c:4244 handle_create drivers/base/devtmpfs.c:233 [inline] handle drivers/base/devtmpfs.c:389 [inline] devtmpfs_work_loop+0x98b/0xd20 drivers/base/devtmpfs.c:404 devtmpfsd+0x4d/0x50 drivers/base/devtmpfs.c:446 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 </TASK> rcu: rcu_preempt kthread starved for 3775 jiffies! g13645 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0 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:26792 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: <TASK> context_switch kernel/sched/core.c:5397 [inline] __schedule+0x16f5/0x4d00 kernel/sched/core.c:6786 __schedule_loop kernel/sched/core.c:6864 [inline] schedule+0x165/0x360 kernel/sched/core.c:6879 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2054 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2256 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 </TASK> rcu: Stack dump where RCU GP kthread last ran: CPU: 0 UID: 0 PID: 6170 Comm: syz.1.17 Not tainted 6.16.0-rc6-syzkaller-00002-g155a3c003e55 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline] RIP: 0010:smp_call_function_many_cond+0xf69/0x12d0 kernel/smp.c:885 Code: 00 45 8b 2f 44 89 ee 83 e6 01 31 ff e8 d0 78 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 7b 74 0b 00 eb 37 f3 90 <43> 0f b6 04 2c 84 c0 75 10 41 f7 07 01 00 00 00 74 1e e8 60 74 0b RSP: 0018:ffffc90003aaf360 EFLAGS: 00000293 RAX: ffffffff81b4bf10 RBX: ffff8880b863b1c0 RCX: ffff88802b8b9e00 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc90003aaf4c0 R08: ffffffff8fa1f5f7 R09: 1ffffffff1f43ebe R10: dffffc0000000000 R11: fffffbfff1f43ebf R12: 1ffff110170e7f5d R13: dffffc0000000000 R14: 0000000000000001 R15: ffff8880b873fae8 FS: 0000000000000000(0000) GS:ffff888125c1b000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fd071f81ab8 CR3: 000000000df38000 CR4: 00000000003526f0 Call Trace: <TASK> on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1052 __flush_tlb_multi arch/x86/include/asm/paravirt.h:91 [inline] flush_tlb_multi arch/x86/mm/tlb.c:1361 [inline] flush_tlb_mm_range+0x6b1/0x12c0 arch/x86/mm/tlb.c:1451 tlb_flush arch/x86/include/asm/tlb.h:23 [inline] tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:490 [inline] tlb_flush_mmu+0x1a7/0x680 mm/mmu_gather.c:403 tlb_finish_mmu+0xc3/0x1d0 mm/mmu_gather.c:497 free_ldt_pgtables+0x17b/0x320 arch/x86/kernel/ldt.c:411 arch_exit_mmap arch/x86/include/asm/mmu_context.h:234 [inline] exit_mmap+0x17c/0xb50 mm/mmap.c:1270 __mmput+0x118/0x420 kernel/fork.c:1121 exit_mm+0x1da/0x2c0 kernel/exit.c:581 do_exit+0x648/0x22e0 kernel/exit.c:952 do_group_exit+0x21c/0x2d0 kernel/exit.c:1105 get_signal+0x1286/0x1340 kernel/signal.c:3034 arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:111 exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline] do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7efe165c11e5 Code: Unable to access opcode bytes at 0x7efe165c11bb. RSP: 002b:00007ffe8f0552d0 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6 RAX: 0000000000000000 RBX: 0000000000000003 RCX: 00007efe165c11e5 RDX: 00007ffe8f055310 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000293 R12: 00007ffe8f055368 R13: 0000200000000080 R14: 00007efe167b5fa0 R15: 0000000000000003 </TASK> sched: DL replenish lagged too much

Crashes (5):
Time	Kernel	Commit	Syzkaller	Config	Log	Report	Syz repro	C repro	VM info	Assets (help?)	Manager	Title
2025/07/16 14:13	upstream	155a3c003e55	c118d736	.config	console log	report	syz / log	C		[disk image] [vmlinux] [kernel image]	ci-upstream-kasan-gce	INFO: rcu detected stall in devtmpfsd
2026/06/06 17:40	linux-next	f7af91adc230	cc095639	.config	console log	report	syz / log	C		[disk image] [vmlinux] [kernel image]	ci-upstream-rust-kasan-gce	INFO: rcu detected stall in devtmpfsd
2026/01/20 07:03	upstream	24d479d26b25	d1b870e1	.config	console log	report			info	[disk image] [vmlinux] [kernel image]	ci-qemu-gce-upstream-auto	INFO: rcu detected stall in devtmpfsd
2025/09/28 23:41	upstream	8f9736633f8c	001c9061	.config	console log	report			info	[disk image] [vmlinux] [kernel image]	ci-upstream-kasan-gce	INFO: rcu detected stall in devtmpfsd
2025/08/22 08:37	linux-next	7fa4d8dc380f	bf27483f	.config	console log	report			info	[disk image] [vmlinux] [kernel image]	ci-upstream-linux-next-kasan-gce-root	INFO: rcu detected stall in devtmpfsd

Crashes (5):

Assets (help?)