syzbot

 sign-in | mailing list | source | docs
🐞 Open [1471]
≡ Subsystems
🐞 Fixed [6729]
🐞 Invalid [17288]
⬇ Missing Backports [220]
≡ Crashes
Kernel Health Bugs/Month Bug Lifetimes Fuzzing
Total Repo Heatmap Subsystems Heatmap
💬 Send us feedback

INFO: rcu detected stall in timerfd_release (4)

Status: auto-obsoleted due to no activity on 2025/01/20 14:31
Subsystems: fs
[Documentation on labels]
First crash: 411d, last: 387d
▶ ▼ Similar bugs (5)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in timerfd_release fs 1 2 1278d 1346d 0/29 auto-closed as invalid on 2022/08/12 21:39
upstream INFO: rcu detected stall in timerfd_release (2) fs 1 1 857d 857d 0/29 auto-obsoleted due to no activity on 2023/10/07 22:46
upstream INFO: rcu detected stall in timerfd_release (5) fs 1 2 171d 218d 0/29 auto-obsoleted due to no activity on 2025/08/24 16:23
upstream INFO: rcu detected stall in timerfd_release (3) kernel 1 4 527d 570d 0/29 auto-obsoleted due to no activity on 2024/09/02 07:15
linux-6.1 INFO: rcu detected stall in timerfd_release 1 1 303d 303d 0/3 auto-obsoleted due to no activity on 2025/04/24 16:10

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (1 GPs behind) idle=1184/1/0x4000000000000000 softirq=51939/51943 fqs=14
rcu: 	(detected by 0, t=10502 jiffies, g=55217, q=256 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 14759 Comm: syz.4.4258 Not tainted 6.12.0-rc4-syzkaller-00047-gc2ee9f594da8 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:arch_test_and_set_bit arch/x86/include/asm/bitops.h:137 [inline]
RIP: 0010:test_and_set_bit include/asm-generic/bitops/instrumented-atomic.h:72 [inline]
RIP: 0010:__netif_schedule+0x9e/0x310 net/core/dev.c:3137
Code: 43 c6 44 2e 0b f3 e8 31 ea 0a f8 49 8d bc 24 58 01 00 00 be 08 00 00 00 e8 7f 8e 71 f8 31 db f0 49 0f ba ac 24 58 01 00 00 00 <41> 0f 93 c7 0f 92 c3 bf 02 00 00 00 89 de e8 ff ec 0a f8 31 ff 89
RSP: 0018:ffffc90000a18ba0 EFLAGS: 00000047
RAX: ffffffff8989ed01 RBX: 0000000000000000 RCX: ffffffff8989ed71
RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffff888022b24158
RBP: ffffc90000a18c80 R08: ffff888022b2415f R09: 1ffff1100456482b
R10: dffffc0000000000 R11: ffffed100456482c R12: ffff888022b24000
R13: dffffc0000000000 R14: 1ffff92000143178 R15: ffff888022b24360
FS:  0000555587a94500(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c42b578 CR3: 0000000043e10000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 advance_sched+0xaa9/0xca0 net/sched/sch_taprio.c:986
 __run_hrtimer kernel/time/hrtimer.c:1691 [inline]
 __hrtimer_run_queues+0x59b/0xd50 kernel/time/hrtimer.c:1755
 hrtimer_interrupt+0x396/0x990 kernel/time/hrtimer.c:1817
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline]
 __sysvec_apic_timer_interrupt+0x110/0x420 arch/x86/kernel/apic/apic.c:1055
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
 sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1049
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:orc_ip arch/x86/kernel/unwind_orc.c:80 [inline]
RIP: 0010:__orc_find arch/x86/kernel/unwind_orc.c:102 [inline]
RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:227 [inline]
RIP: 0010:unwind_next_frame+0x6dc/0x22d0 arch/x86/kernel/unwind_orc.c:494
Code: c1 e8 3f 48 01 c8 48 83 e0 fe 49 8d 1c 46 48 89 d8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 0f b6 04 08 84 c0 75 27 48 63 03 <48> 01 d8 48 8d 4b 04 4c 39 f8 4c 0f 46 f1 48 8d 43 fc 48 0f 47 e8
RSP: 0018:ffffc9000a757790 EFLAGS: 00000246
RAX: fffffffff14c28a4 RBX: ffffffff902ec314 RCX: dffffc0000000000
RDX: 00000000000b0001 RSI: ffffffff90a528b2 RDI: ffffffff814156e0
RBP: ffffffff902ec314 R08: 0000000000000001 R09: ffffc9000a757950
R10: ffffc9000a7578b0 R11: ffffffff81809070 R12: ffffffff902ec314
R13: ffffffff902ec314 R14: ffffffff902ec314 R15: ffffffff817aecab
 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122
 kasan_save_stack+0x3f/0x60 mm/kasan/common.c:47
 __kasan_record_aux_stack+0xac/0xc0 mm/kasan/generic.c:541
 kvfree_call_rcu+0xfc/0x790 kernel/rcu/tree.c:3810
 timerfd_release+0x1ca/0x250 fs/timerfd.c:245
 __fput+0x23f/0x880 fs/file_table.c:431
 task_work_run+0x24f/0x310 kernel/task_work.c:239
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x168/0x370 kernel/entry/common.c:218
 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fdcf1d7dff9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fff794471b8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 000000000005276c RCX: 00007fdcf1d7dff9
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007fdcf1f37a80 R08: 0000000000000001 R09: 00007fff794474af
R10: 00007fdcf1c00000 R11: 0000000000000246 R12: 00000000000527a9
R13: 00007fff794472c0 R14: 0000000000000032 R15: ffffffffffffffff
 </TASK>
rcu: rcu_preempt kthread starved for 10474 jiffies! g55217 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:26112 pid:17    tgid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5328 [inline]
 __schedule+0x185a/0x4b70 kernel/sched/core.c:6690
 __schedule_loop kernel/sched/core.c:6767 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6782
 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2615
 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2045
 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2247
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 5267 Comm: kworker/0:5 Not tainted 6.12.0-rc4-syzkaller-00047-gc2ee9f594da8 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Workqueue: events once_deferred
RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline]
RIP: 0010:smp_call_function_many_cond+0x19f3/0x2ca0 kernel/smp.c:884
Code: 45 8b 65 00 44 89 e6 83 e6 01 31 ff e8 56 f3 0b 00 41 83 e4 01 49 bc 00 00 00 00 00 fc ff df 75 07 e8 01 ef 0b 00 eb 38 f3 90 <42> 0f b6 04 23 84 c0 75 11 41 f7 45 00 01 00 00 00 74 1e e8 e5 ee
RSP: 0018:ffffc90003eff7a0 EFLAGS: 00000293
RAX: ffffffff8188e8ab RBX: 1ffff110170e8911 RCX: ffff8880626c5a00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90003eff9a0 R08: ffffffff8188e87a R09: 1ffffffff2852700
R10: dffffc0000000000 R11: fffffbfff2852701 R12: dffffc0000000000
R13: ffff8880b8744888 R14: ffff8880b863fc40 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f93d4b1ef98 CR3: 000000000e734000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 </IRQ>
 <TASK>
 on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1051
 on_each_cpu include/linux/smp.h:71 [inline]
 text_poke_sync arch/x86/kernel/alternative.c:2085 [inline]
 text_poke_bp_batch+0x352/0xb30 arch/x86/kernel/alternative.c:2295
 text_poke_flush arch/x86/kernel/alternative.c:2486 [inline]
 text_poke_finish+0x30/0x50 arch/x86/kernel/alternative.c:2493
 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
 static_key_disable_cpuslocked+0xd2/0x1c0 kernel/jump_label.c:240
 static_key_disable+0x1a/0x20 kernel/jump_label.c:248
 once_deferred+0x70/0xb0 lib/once.c:20
 process_one_work kernel/workqueue.c:3229 [inline]
 process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310
 worker_thread+0x870/0xd30 kernel/workqueue.c:3391
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/10/22 14:29 upstream c2ee9f594da8 9d74f456 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: rcu detected stall in timerfd_release
2024/10/02 14:38 upstream e32cde8d2bd7 a4c7fd36 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: rcu detected stall in timerfd_release
2024/09/28 18:09 upstream 3efc57369a0c ba29ff75 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: rcu detected stall in timerfd_release
* Struck through repros no longer work on HEAD.