INFO: rcu detected stall in worker_thread (2)

Status: auto-obsoleted due to no activity on 2025/05/01 18:18
Reported-by: syzbot+9e6094058b8fa0c726a4@syzkaller.appspotmail.com
First crash: 589d, last: 589d
▶ ▼ Similar bugs (17)
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 2429d 2429d 0/29 closed as invalid on 2020/01/08 05:33
upstream INFO: rcu detected stall in worker_thread (4) mm cgroups 1 28 2429d 2429d 0/29 closed as invalid on 2020/01/09 08:13
linux-5.15 INFO: rcu detected stall in worker_thread 1 1 1069d 1069d 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 1212d 1212d 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 1553d 1590d 0/29 auto-closed as invalid on 2022/08/31 00:50
android-6-12 INFO: rcu detected stall in worker_thread 1 1 326d 326d 0/1 auto-obsoleted due to no activity on 2026/01/09 16:24
upstream INFO: rcu detected stall in worker_thread (9) prio:low netfilter 1 syz, C done 5888 4h49m 1061d 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 2429d 2429d 0/29 closed as invalid on 2020/01/08 05:23
upstream INFO: rcu detected stall in worker_thread mm cgroups 1 150 2464d 2465d 0/29 closed as invalid on 2019/12/04 14:14
linux-6.1 INFO: rcu detected stall in worker_thread 1 6 805d 835d 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 syz, C done 334 3d20h 441d 0/2 upstream: reported C repro on 2025/06/18 07:15
upstream INFO: rcu detected stall in worker_thread (6) kernel 1 1 1429d 1429d 0/29 auto-obsoleted due to no activity on 2023/01/12 15:50
linux-6.1 INFO: rcu detected stall in worker_thread (3) 1 2 16d 44d 0/3 upstream: reported on 2026/07/20 15:45
linux-5.15 INFO: rcu detected stall in worker_thread (2) 1 4 808d 813d 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 1322d 1322d 0/29 auto-obsoleted due to no activity on 2023/04/27 16:37
upstream INFO: task hung in crda_timeout_work (8) wireless prio:high 1 syz, C done error 723 5h16m 705d 0/29 upstream: reported C repro on 2024/09/27 16:53
android-5-15 BUG: soft lockup in worker_thread origin:lts 1 syz, C done 1 737d 737d 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: 	1-...!: (1 ticks this GP) idle=d79c/1/0x4000000000000000 softirq=53682/53682 fqs=14
	(detected by 0, t=10504 jiffies, g=73061, q=448 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 33 Comm: kworker/u4:2 Not tainted 6.1.126-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
Workqueue:  0x0 (phy31)
RIP: 0010:bytes_is_nonzero mm/kasan/generic.c:85 [inline]
RIP: 0010:memory_is_nonzero mm/kasan/generic.c:102 [inline]
RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:128 [inline]
RIP: 0010:memory_is_poisoned mm/kasan/generic.c:159 [inline]
RIP: 0010:check_region_inline mm/kasan/generic.c:180 [inline]
RIP: 0010:kasan_check_range+0x7b/0x290 mm/kasan/generic.c:189
Code: 00 00 00 00 fc ff df 4f 8d 34 1a 4c 89 f5 4c 29 cd 48 83 fd 10 7f 26 48 85 ed 0f 84 3a 01 00 00 49 f7 d2 49 01 da 41 80 39 00 <0f> 85 c4 01 00 00 49 ff c1 49 ff c2 75 ee e9 1d 01 00 00 45 89 cf
RSP: 0018:ffffc900001e06f8 EFLAGS: 00000046
RAX: 0000000000000001 RBX: 1ffffffff2249c4c RCX: ffffffff816b5ea2
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff9124e260
RBP: 0000000000000001 R08: dffffc0000000000 R09: fffffbfff2249c4c
R10: ffffffffffffffff R11: dffffc0000000001 R12: dffffc0000000000
R13: ffff88801aeaa8e8 R14: fffffbfff2249c4d R15: 1ffff110035d551d
FS:  0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000240 CR3: 000000005cda3000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 instrument_atomic_read include/linux/instrumented.h:72 [inline]
 _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
 hlock_class kernel/locking/lockdep.c:228 [inline]
 lookup_chain_cache_add kernel/locking/lockdep.c:3737 [inline]
 validate_chain+0x112/0x5950 kernel/locking/lockdep.c:3793
 __lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5049
 lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162
 debug_object_activate+0x68/0x4e0 lib/debugobjects.c:698
 debug_hrtimer_activate kernel/time/hrtimer.c:421 [inline]
 debug_activate kernel/time/hrtimer.c:476 [inline]
 enqueue_hrtimer+0x30/0x410 kernel/time/hrtimer.c:1085
 __run_hrtimer kernel/time/hrtimer.c:1706 [inline]
 __hrtimer_run_queues+0x728/0xe50 kernel/time/hrtimer.c:1753
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1815
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1107 [inline]
 __sysvec_apic_timer_interrupt+0x158/0x5b0 arch/x86/kernel/apic/apic.c:1124
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
 sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1118
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:finish_task_switch+0x1d3/0x810 kernel/sched/core.c:5120
Code: 38 0b 00 48 83 c4 08 4c 89 f7 e8 68 31 00 00 0f 1f 44 00 00 4c 89 f7 e8 6b c5 5d 09 e8 66 f3 31 00 fb 49 8d bc 24 f8 15 00 00 <48> 89 f8 48 c1 e8 03 49 bd 00 00 00 00 00 fc ff df 42 0f b6 04 28
RSP: 0018:ffffc90000aa7ba8 EFLAGS: 00000286
RAX: 165841413b576800 RBX: ffff888017f50034 RCX: ffffffff97355103
RDX: dffffc0000000000 RSI: ffffffff8b0c0340 RDI: ffff88801aeab3b8
RBP: ffffc90000aa7bf0 R08: dffffc0000000000 R09: ffffed10171e7539
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff88801aea9dc0
R13: 1ffff110171e76e3 R14: ffff8880b8f3a9c0 R15: ffff8880b8f3b718
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x1447/0x4570 kernel/sched/core.c:6558
 schedule+0xbf/0x180 kernel/sched/core.c:6634
 worker_thread+0xe9d/0x1200 kernel/workqueue.c:2460
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
rcu: rcu_preempt kthread starved for 10435 jiffies! g73061 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:26136 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5241 [inline]
 __schedule+0x143f/0x4570 kernel/sched/core.c:6558
 schedule+0xbf/0x180 kernel/sched/core.c:6634
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1965
 rcu_gp_fqs_loop+0x2d2/0x1150 kernel/rcu/tree.c:1706
 rcu_gp_kthread+0xa3/0x3b0 kernel/rcu/tree.c:1905
 kthread+0x28d/0x320 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:
CPU: 0 PID: 13671 Comm: syz.6.2947 Not tainted 6.1.126-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
RIP: 0010:csd_lock_wait kernel/smp.c:424 [inline]
RIP: 0010:smp_call_function_many_cond+0x1fc4/0x3460 kernel/smp.c:998
Code: 00 00 00 fc ff df 75 0a e8 99 40 0b 00 e9 1b ff ff ff f3 90 42 0f b6 04 2b 84 c0 75 14 41 f7 07 01 00 00 00 0f 84 fe fe ff ff <e8> 77 40 0b 00 eb e1 44 89 f9 80 e1 07 80 c1 03 38 c1 7c df 4c 89
RSP: 0018:ffffc900050e74e0 EFLAGS: 00000202
RAX: 0000000000000000 RBX: 1ffff110171e81b1 RCX: ffff888029b89dc0
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc900050e78c0 R08: ffffffff817f5b52 R09: fffff52000a1ce8d
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000800000000
R13: dffffc0000000000 R14: 0000000000000001 R15: ffff8880b8f40d88
FS:  0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c380a1b CR3: 000000005c4b3000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 </IRQ>
 <TASK>
 on_each_cpu_cond_mask+0x3b/0x80 kernel/smp.c:1166
 __flush_tlb_multi arch/x86/include/asm/paravirt.h:87 [inline]
 flush_tlb_multi arch/x86/mm/tlb.c:924 [inline]
 flush_tlb_mm_range+0x353/0x590 arch/x86/mm/tlb.c:1010
 tlb_flush arch/x86/include/asm/tlb.h:20 [inline]
 tlb_flush_mmu_tlbonly+0x1ab/0x410 include/asm-generic/tlb.h:430
 tlb_flush_mmu+0x28/0x210 mm/mmu_gather.c:260
 tlb_finish_mmu+0xce/0x1f0 mm/mmu_gather.c:361
 exit_mmap+0x3b3/0x980 mm/mmap.c:3250
 __mmput+0x115/0x3c0 kernel/fork.c:1200
 exit_mm+0x226/0x300 kernel/exit.c:565
 do_exit+0x9f1/0x26a0 kernel/exit.c:858
 do_group_exit+0x202/0x2b0 kernel/exit.c:1021
 __do_sys_exit_group kernel/exit.c:1032 [inline]
 __se_sys_exit_group kernel/exit.c:1030 [inline]
 __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1030
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f6053785d29
Code: Unable to access opcode bytes at 0x7f6053785cff.
RSP: 002b:00007ffebc2eaf98 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f6053785d29
RDX: 00007f60523f9000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ffebc2eafec R08: 0000000000000090 R09: 00000000000664dc
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000032
R13: 00000000000664dc R14: 00007ffebc2eb040 R15: 00007ffebc2eb040
 </TASK>
vkms_vblank_simulate: vblank timer overrun

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/01/21 18:17 linux-6.1.y f4f677285b38 da72ac06 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in worker_thread
* Struck through repros no longer work on HEAD.