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INFO: rcu detected stall in sys_openat (2)

Status: upstream: reported C repro on 2024/03/13 11:37
Bug presence: origin:upstream
[Documentation on labels]
Reported-by: syzbot+9854cfdd44796d239bec@syzkaller.appspotmail.com
First crash: 840d, last: 23h49m
Fix bisection: failed (error log, bisect log)
  
▶ ▼ Bug presence (1)
Date Name Commit Repro Result
2024/03/13 upstream (ToT) 259f7d5e2baf C [report] INFO: rcu detected stall in worker_thread
▶ ▼ Similar bugs (9)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 INFO: rcu detected stall in sys_openat 1 3 1028d 1061d 0/3 auto-obsoleted due to no activity on 2023/12/16 21:24
upstream INFO: rcu detected stall in sys_openat exfat 1 5 2726d 2804d 0/29 closed as dup on 2018/10/27 13:02
linux-5.15 INFO: rcu detected stall in sys_openat missing-backport origin:upstream 1 C done 71 8d14h 1108d 0/3 upstream: reported C repro on 2023/06/19 20:52
linux-6.6 INFO: rcu detected stall in sys_openat origin:lts-only 1 C inconclusive 16 5d17h 357d 0/2 upstream: reported C repro on 2025/07/10 07:34
upstream INFO: rcu detected stall in sys_openat (3) prio:low mm 1 C error 625 3h15m 1032d 0/29 upstream: reported C repro on 2023/09/03 11:10
upstream INFO: rcu detected stall in sys_openat (2) kernfs 1 8 1609d 1821d 0/29 closed as invalid on 2022/02/08 09:50
android-5-15 BUG: soft lockup in sys_openat (2) origin:lts 1 C error 5 659d 709d 0/2 auto-obsoleted due to no activity on 2024/12/19 09:52
android-5-10 BUG: soft lockup in sys_openat 1 1 283d 283d 0/2 auto-obsoleted due to no activity on 2025/12/20 20:57
android-5-15 BUG: soft lockup in sys_openat 1 21 760d 815d 0/2 auto-obsoleted due to no activity on 2024/07/21 23:03
▶ ▼ Fix bisection attempts (8)
Created Duration User Patch Repo Result
2025/07/02 13:41 6m bisect fix linux-6.1.y error job log
2025/04/14 19:25 2h12m bisect fix linux-6.1.y OK (0) job log log
2025/02/23 16:12 2h27m bisect fix linux-6.1.y OK (0) job log log
2025/01/09 11:26 2h57m bisect fix linux-6.1.y OK (0) job log log
2024/11/19 10:30 1h21m bisect fix linux-6.1.y OK (0) job log log
2024/10/15 19:20 2h14m bisect fix linux-6.1.y OK (0) job log log
2024/05/20 02:32 1h25m bisect fix linux-6.1.y OK (0) job log log
2024/04/16 07:43 2h24m bisect fix linux-6.1.y OK (0) job log log

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P4271/1:b..l
	(detected by 1, t=10503 jiffies, g=5441, q=24 ncpus=2)
task:syz-executor114 state:R  running task     stack:26240 pid:4271  ppid:4266   flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
 preempt_schedule_irq+0xb1/0x150 kernel/sched/core.c:6873
 irqentry_exit+0x63/0x70 kernel/entry/common.c:439
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:lock_acquire+0x20f/0x490 kernel/locking/lockdep.c:5666
Code: 00 9c 8f 84 24 80 00 00 00 f6 84 24 81 00 00 00 02 0f 85 f5 00 00 00 41 f7 c6 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45 <4b> c7 44 3d 00 00 00 00 00 66 43 c7 44 3d 09 00 00 43 c6 44 3d 0b
RSP: 0018:ffffc90003ca7740 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 0000000000000000 RCX: ce219cc200123700
RDX: 0000000000000000 RSI: ffffffff8a8c1700 RDI: ffffffff8adef3a0
RBP: ffffc90003ca7858 R08: dffffc0000000000 R09: fffffbfff215c449
R10: fffffbfff215c449 R11: 1ffffffff215c448 R12: 0000000000000001
R13: 1ffff92000794ef4 R14: 0000000000000246 R15: dffffc0000000000
 rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
 rcu_read_lock include/linux/rcupdate.h:791 [inline]
 is_bpf_text_address+0x43/0x2a0 kernel/bpf/core.c:735
 kernel_text_address+0x9c/0xd0 kernel/extable.c:125
 __kernel_text_address+0x9/0x30 kernel/extable.c:79
 unwind_get_return_address+0x49/0x80 arch/x86/kernel/unwind_orc.c:323
 arch_stack_walk+0xf2/0x140 arch/x86/kernel/stacktrace.c:26
 stack_trace_save+0x98/0xe0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 __kasan_slab_alloc+0x6b/0x80 mm/kasan/common.c:328
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook+0x4b/0x480 mm/slab.h:737
 slab_alloc_node mm/slub.c:3359 [inline]
 slab_alloc mm/slub.c:3367 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3374 [inline]
 kmem_cache_alloc+0x123/0x2f0 mm/slub.c:3383
 getname_flags+0xb7/0x500 fs/namei.c:139
 do_sys_openat2+0xcf/0x490 fs/open.c:1312
 do_sys_open fs/open.c:1334 [inline]
 __do_sys_openat fs/open.c:1350 [inline]
 __se_sys_openat fs/open.c:1345 [inline]
 __x64_sys_openat+0x135/0x160 fs/open.c:1345
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f4ef48ba750
RSP: 002b:00007ffd319324f0 EFLAGS: 00000293 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000080001 RCX: 00007f4ef48ba750
RDX: 0000000000080001 RSI: 00007f4ef49132d8 RDI: 00000000ffffff9c
RBP: 00007f4ef49132d8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 00007ffd31932590
R13: 0000000000000003 R14: 0000000000000003 R15: 0000000000000001
 </TASK>
rcu: rcu_preempt kthread starved for 10545 jiffies! g5441 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:28192 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
 schedule+0xb9/0x180 kernel/sched/core.c:6637
 schedule_timeout+0x15c/0x280 kernel/time/timer.c:1965
 rcu_gp_fqs_loop+0x2f2/0x1310 kernel/rcu/tree.c:1706
 rcu_gp_kthread+0x95/0x380 kernel/rcu/tree.c:1905
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 4292 Comm: syz-executor114 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:get_current arch/x86/include/asm/current.h:15 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:244 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x4/0x80 kernel/kcov.c:313
Code: 77 22 89 ff 89 f6 49 ff c0 4c 89 01 48 c7 44 11 08 03 00 00 00 48 89 7c 11 10 48 89 74 11 18 48 89 44 11 20 c3 90 48 8b 04 24 <65> 48 8b 15 c4 98 81 7e 65 8b 0d c5 98 81 7e 81 e1 00 01 ff 00 74
RSP: 0018:ffffc90003d57af0 EFLAGS: 00000046
RAX: ffffffff815041a9 RBX: 0000000000000021 RCX: ffff88801e2fbb80
RDX: 0000000000000000 RSI: 00000000004be77f RDI: 0000000000000000
RBP: 00000000004be77f R08: dffffc0000000000 R09: fffff520007aafc6
R10: fffff520007aafc6 R11: 1ffff920007aafc0 R12: ffffc90003d57e20
R13: ffff8880777be860 R14: dffffc0000000000 R15: 1ffff1100eef7d0c
FS:  000055555f0603c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000020000006b000 CR3: 00000000767c2000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 collect_signal kernel/signal.c:599 [inline]
 __dequeue_signal+0x419/0x610 kernel/signal.c:624
 dequeue_signal+0xe5/0x4b0 kernel/signal.c:647
 get_signal+0x547/0x1350 kernel/signal.c:2751
 arch_do_signal_or_restart+0xb7/0x1240 arch/x86/kernel/signal.c:871
 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f4ef48bb8d9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 11 19 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffd31932898 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000003 RCX: 00007f4ef48bb8d9
RDX: 000020000006b000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 00007f4ef487b990 R09: 00007f4ef487b990
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f4ef491933c
R13: 00007f4ef4913106 R14: 00007ffd319328d0 R15: 0000000000000000
 </TASK>
sched: RT throttling activated
hrtimer: interrupt took 912179965 ns

Crashes (47):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/10/23 17:01 linux-6.1.y 8e6e2188d949 c0460fcd .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_openat
2024/03/13 11:37 linux-6.1.y 61adba85cc40 db5b7ff0 .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_openat
2025/11/28 22:18 linux-6.1.y f6e38ae624cf d6526ea3 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_openat
2025/03/11 06:11 linux-6.1.y 6ae7ac5c4251 16256247 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_openat
2025/12/11 16:05 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 INFO: rcu detected stall in sys_openat
2026/07/01 08:15 linux-6.1.y fdb6fcb41cc7 00a5cf1c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_openat
2026/06/29 03:25 linux-6.1.y fdb6fcb41cc7 fb92f11c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_openat
2026/06/27 11:41 linux-6.1.y fdb6fcb41cc7 fb92f11c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_openat
2026/06/25 03:39 linux-6.1.y fdb6fcb41cc7 302586aa .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_openat
2026/06/19 07:01 linux-6.1.y 228da13e907e a776b0d0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_openat
2026/06/17 19:36 linux-6.1.y 228da13e907e b62b3ded .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_openat
2026/06/17 11:01 linux-6.1.y 228da13e907e 62cc6db3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_openat
2026/05/26 07:06 linux-6.1.y dcbcab9d7079 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_openat
2026/05/25 23:09 linux-6.1.y dcbcab9d7079 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_openat
2026/04/27 07:06 linux-6.1.y 7c87defbd336 9c2d0995 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_openat
2026/04/05 23:25 linux-6.1.y 1989cd3d56e2 4440e7c2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_openat
2026/03/31 15:19 linux-6.1.y 1989cd3d56e2 aeea1c72 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_openat
2026/03/27 10:19 linux-6.1.y 1989cd3d56e2 766b6434 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_openat
2026/02/22 06:43 linux-6.1.y 779f9571ac3e 6e7b5511 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_openat
2026/02/22 01:26 linux-6.1.y 779f9571ac3e 6e7b5511 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_openat
2026/02/13 00:50 linux-6.1.y 8ce36b2849ef 504cb1bf .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_openat
2026/01/16 08:07 linux-6.1.y bec0e10ee67e d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_openat
2026/01/07 04:33 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_openat
2025/12/04 23:36 linux-6.1.y f6e38ae624cf d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_openat
2025/11/16 09:18 linux-6.1.y f6e38ae624cf f7988ea4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_openat
2025/11/14 02:36 linux-6.1.y f6e38ae624cf 07e030de .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_openat
2025/11/02 09:10 linux-6.1.y f6e38ae624cf 2c50b6a9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_openat
2025/10/30 06:28 linux-6.1.y f6e38ae624cf fd2207e7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_openat
2025/10/28 08:02 linux-6.1.y 8e6e2188d949 fd2207e7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_openat
2025/10/02 06:50 linux-6.1.y 7b34dc04e4ff 267f56c6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_openat
2025/09/13 16:18 linux-6.1.y 3db754f56897 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_openat
2025/09/07 00:26 linux-6.1.y 28c695c365e1 d291dd2d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_openat
2025/08/14 15:59 linux-6.1.y 3594f306da12 5d8c2ac2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_openat
2025/06/02 06:11 linux-6.1.y da3c5173c55f 3d2f584d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_openat
2025/06/01 12:47 linux-6.1.y da3c5173c55f 3d2f584d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_openat
2025/06/01 05:37 linux-6.1.y da3c5173c55f 3d2f584d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_openat
2025/05/08 13:17 linux-6.1.y ac7079a42ea5 dbf35fa1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_openat
2025/03/10 10:26 linux-6.1.y 6ae7ac5c4251 163f510d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_openat
2025/01/24 10:06 linux-6.1.y 75cefdf153f5 521b0ce3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_openat
2024/09/15 14:39 linux-6.1.y 5f55cad62cc9 08d8a733 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_openat
2024/08/20 04:29 linux-6.1.y ee5e09825b81 9f0ab3fb .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_openat
2024/08/11 23:44 linux-6.1.y 36790ef5e00b 6f4edef4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_openat
2024/07/27 20:48 linux-6.1.y c1cec4dad96b 46eb10b7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_openat
2024/06/12 09:14 linux-6.1.y 88690811da69 4d75f4f7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_openat
2024/05/27 15:44 linux-6.1.y 88690811da69 761766e6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_openat
2024/06/08 02:54 linux-6.1.y 88690811da69 82c05ab8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 INFO: rcu detected stall in sys_openat
* Struck through repros no longer work on HEAD.