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INFO: rcu detected stall in worker_thread

Status: auto-obsoleted due to no activity on 2026/01/09 16:24
Reported-by: syzbot+a76d54fc6362dea5e941@syzkaller.appspotmail.com
First crash: 258d, last: 258d
▶ ▼ Similar bugs (16)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in worker_thread (3) mm cgroups 1 1 2362d 2362d 0/29 closed as invalid on 2020/01/08 05:33
upstream INFO: rcu detected stall in worker_thread (4) mm cgroups 1 28 2361d 2362d 0/29 closed as invalid on 2020/01/09 08:13
linux-5.15 INFO: rcu detected stall in worker_thread 1 1 1002d 1002d 0/3 auto-obsoleted due to no activity on 2024/01/09 18:17
upstream INFO: rcu detected stall in worker_thread (8) kernel 1 1 1145d 1145d 0/29 auto-obsoleted due to no activity on 2023/08/07 05:14
upstream INFO: rcu detected stall in worker_thread (5) kernel 1 2 1486d 1522d 0/29 auto-closed as invalid on 2022/08/31 00:50
upstream INFO: rcu detected stall in worker_thread (9) prio:low netfilter 1 C done 5386 3h44m 993d 0/29 upstream: reported C repro on 2023/10/07 18:33
upstream INFO: rcu detected stall in worker_thread (2) cgroups mm 1 12 2362d 2362d 0/29 closed as invalid on 2020/01/08 05:23
upstream INFO: rcu detected stall in worker_thread mm cgroups 1 150 2396d 2398d 0/29 closed as invalid on 2019/12/04 14:14
linux-6.1 INFO: rcu detected stall in worker_thread 1 6 737d 767d 0/3 auto-obsoleted due to no activity on 2024/09/27 16:46
linux-6.6 INFO: rcu detected stall in worker_thread origin:lts-only 1 C done 286 2d00h 374d 0/2 upstream: reported C repro on 2025/06/18 07:15
upstream INFO: rcu detected stall in worker_thread (6) kernel 1 1 1361d 1361d 0/29 auto-obsoleted due to no activity on 2023/01/12 15:50
linux-5.15 INFO: rcu detected stall in worker_thread (2) 1 4 741d 746d 0/3 auto-obsoleted due to no activity on 2024/09/24 04:34
upstream INFO: rcu detected stall in worker_thread (7) kernel 1 1 1254d 1254d 0/29 auto-obsoleted due to no activity on 2023/04/27 16:37
linux-6.1 INFO: rcu detected stall in worker_thread (2) 1 1 521d 521d 0/3 auto-obsoleted due to no activity on 2025/05/01 18:18
upstream INFO: task hung in crda_timeout_work (8) wireless prio:high 1 C done error 630 10d 637d 0/29 upstream: reported C repro on 2024/09/27 16:53
android-5-15 BUG: soft lockup in worker_thread origin:lts 1 C done 1 670d 670d 0/2 auto-obsoleted due to no activity on 2024/12/04 04:19

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P64/1:b..l
rcu: 	(detected by 0, t=10002 jiffies, g=17753, q=7543 ncpus=2)
task:kworker/0:2     state:R  running task     stack:0     pid:64    tgid:64    ppid:2      flags:0x00004000
Workqueue: events p9_write_work
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5945 [inline]
 __schedule+0x1322/0x1df0 kernel/sched/core.c:7791
 preempt_schedule_irq+0x9c/0x100 kernel/sched/core.c:8117
 raw_irqentry_exit_cond_resched+0x33/0x40 kernel/entry/common.c:311
 irqentry_exit+0x4a/0x60 kernel/entry/common.c:354
 sysvec_apic_timer_interrupt+0x50/0x90 arch/x86/kernel/apic/apic.c:1049
 asm_sysvec_apic_timer_interrupt+0x1f/0x30 arch/x86/include/asm/idtentry.h:702
RIP: 0010:ebitmap_next_positive security/selinux/ss/ebitmap.h:81 [inline]
RIP: 0010:context_struct_compute_av+0x8ee/0x1680 security/selinux/ss/services.c:653
Code: c8 18 31 00 48 89 c3 83 e0 80 3d 80 01 00 00 72 2d e8 c6 f4 11 ff eb c0 e8 bf f4 11 ff 48 8b 84 24 88 00 00 00 42 0f b6 04 28 <84> c0 0f 85 ab 00 00 00 48 8b 44 24 28 8b 18 45 31 ff eb 20 e8 99
RSP: 0018:ffffc90000d4f340 EFLAGS: 00000293
RAX: 0000000000000000 RBX: 0000000000000180 RCX: ffff888107ee9300
RDX: 0000000000000000 RSI: 0000000000000180 RDI: 0000000000000180
RBP: ffffc90000d4f600 R08: 0000000000000004 R09: 0000000000000004
R10: ffffc90000d4f784 R11: fffff520001a9ef5 R12: 0000000000000180
R13: dffffc0000000000 R14: 1ffff1102137c5c3 R15: 0000000000000000
 security_compute_av+0x38d/0xfa0 security/selinux/ss/services.c:1146
 avc_compute_av+0x89/0x770 security/selinux/avc.c:994
 avc_perm_nonode+0xc8/0x1b0 security/selinux/avc.c:1118
 avc_has_perm_noaudit+0x21c/0x360 security/selinux/avc.c:1161
 avc_has_perm+0xc2/0x220 security/selinux/avc.c:1196
 inode_has_perm security/selinux/hooks.c:1682 [inline]
 file_has_perm security/selinux/hooks.c:1772 [inline]
 selinux_revalidate_file_permission security/selinux/hooks.c:3626 [inline]
 selinux_file_permission+0x88b/0xb30 security/selinux/hooks.c:3647
 security_file_permission+0x4c/0xc0 security/security.c:2845
 rw_verify_area fs/read_write.c:471 [inline]
 kernel_write+0x11b/0x6b0 fs/read_write.c:653
 p9_fd_write net/9p/trans_fd.c:433 [inline]
 p9_write_work+0x551/0xd30 net/9p/trans_fd.c:484
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0x7d2/0x1020 kernel/workqueue.c:3319
 worker_thread+0xc58/0x1250 kernel/workqueue.c:3400
 kthread+0x2ca/0x370 kernel/kthread.c:389
 ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/10/11 16:23 android16-6.12 fbb5490cc8c3 ff1712fe .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: rcu detected stall in worker_thread
* Struck through repros no longer work on HEAD.