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INFO: rcu detected stall in worker_thread

Status: upstream: reported on 2024/05/20 10:24
Reported-by: syzbot+d3a4308cd2ba5cfd5b8c@syzkaller.appspotmail.com
First crash: 68d, last: 37d
▶ ▼ Similar bugs (11)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in worker_thread (3) cgroups mm 1 1662d 1662d 0/27 closed as invalid on 2020/01/08 05:33
upstream INFO: rcu detected stall in worker_thread (4) cgroups mm 28 1662d 1662d 0/27 closed as invalid on 2020/01/09 08:13
linux-5.15 INFO: rcu detected stall in worker_thread 1 302d 302d 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 445d 445d 0/27 auto-obsoleted due to no activity on 2023/08/07 05:14
upstream INFO: rcu detected stall in worker_thread (5) kernel 2 786d 823d 0/27 auto-closed as invalid on 2022/08/31 00:50
upstream INFO: rcu detected stall in worker_thread (9) mm netfilter batman C done 1511 1h42m 293d 0/27 upstream: reported C repro on 2023/10/07 18:33
upstream INFO: rcu detected stall in worker_thread (2) cgroups mm 12 1662d 1662d 0/27 closed as invalid on 2020/01/08 05:23
upstream INFO: rcu detected stall in worker_thread cgroups mm 150 1697d 1698d 0/27 closed as invalid on 2019/12/04 14:14
upstream INFO: rcu detected stall in worker_thread (6) kernel 1 662d 662d 0/27 auto-obsoleted due to no activity on 2023/01/12 15:50
linux-5.15 INFO: rcu detected stall in worker_thread (2) 4 41d 46d 0/3 upstream: reported on 2024/06/10 22:16
upstream INFO: rcu detected stall in worker_thread (7) kernel 1 554d 554d 0/27 auto-obsoleted due to no activity on 2023/04/27 16:37

Sample crash report:
rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-...!: (10507 ticks this GP) idle=d50c/1/0x4000000000000000 softirq=15073/15075 fqs=6
	(t=10500 jiffies g=18737 q=20 ncpus=2)
rcu: rcu_preempt kthread starved for 10482 jiffies! g18737 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
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:25528 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x142d/0x4550 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:308
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 3549 Comm: syz-fuzzer Not tainted 6.1.94-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x7c/0x80 kernel/kcov.c:306
Code: 8d 42 28 4c 39 c8 77 22 89 f8 89 f6 49 ff c2 4c 89 11 48 c7 44 0a 08 05 00 00 00 48 89 44 0a 10 48 89 74 0a 18 4c 89 44 0a 20 <c3> 0f 1f 00 4c 8b 04 24 65 48 8b 0d 04 d8 77 7e 65 8b 05 05 d8 77
RSP: 0018:ffffc90003a7f580 EFLAGS: 00000093
RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffff888027180000
RDX: ffff888027180000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000020 R08: ffffffff8197646c R09: ffffed10173267b3
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff8880b9933d90
R13: 1ffff9200074fe00 R14: ffff8880b9933d88 R15: 0000000000000020
FS:  000000c000ea6090(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b32b36000 CR3: 000000006f41f000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 irq_work_claim kernel/irq_work.c:65 [inline]
 irq_work_queue+0x8c/0x150 kernel/irq_work.c:109
 bpf_send_signal_common+0x2ba/0x420 kernel/trace/bpf_trace.c:878
 ____bpf_send_signal kernel/trace/bpf_trace.c:887 [inline]
 bpf_send_signal+0x15/0x20 kernel/trace/bpf_trace.c:885
 bpf_prog_9fbc3d1d47c9b36c+0x1a/0x21
 bpf_dispatcher_nop_func include/linux/bpf.h:989 [inline]
 __bpf_prog_run include/linux/filter.h:603 [inline]
 bpf_prog_run include/linux/filter.h:610 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:2273 [inline]
 bpf_trace_run1+0x1d9/0x3d0 kernel/trace/bpf_trace.c:2311
 trace_rcu_utilization+0x1e5/0x230 include/trace/events/rcu.h:27
 rcu_note_context_switch+0xc5/0xf30 kernel/rcu/tree_plugin.h:318
 __schedule+0x32e/0x4550 kernel/sched/core.c:6458
 schedule+0xbf/0x180 kernel/sched/core.c:6634
 futex_wait_queue+0x149/0x1d0 kernel/futex/waitwake.c:355
 futex_wait+0x203/0x5c0 kernel/futex/waitwake.c:656
 do_futex+0x3b5/0x490 kernel/futex/syscalls.c:106
 __do_sys_futex kernel/futex/syscalls.c:183 [inline]
 __se_sys_futex+0x3d7/0x460 kernel/futex/syscalls.c:164
 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: 0033:0x473523
Code: 24 20 c3 cc cc cc cc 48 8b 7c 24 08 8b 74 24 10 8b 54 24 14 4c 8b 54 24 18 4c 8b 44 24 20 44 8b 4c 24 28 b8 ca 00 00 00 0f 05 <89> 44 24 30 c3 cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc
RSP: 002b:000000c000eb7ef0 EFLAGS: 00000286 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000473523
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 0000000002600ff8
RBP: 000000c000eb7f38 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000286 R12: 000000000046f7e0
R13: 000000c000ea6800 R14: 000000c0000bda00 R15: 0000000000000010
 </TASK>
CPU: 0 PID: 1027 Comm: kworker/0:1H Not tainted 6.1.94-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
Workqueue:  0x0 (kblockd)
RIP: 0010:finish_task_switch+0x1d3/0x810 kernel/sched/core.c:5124
Code: 2e 0b 00 48 83 c4 08 4c 89 f7 e8 98 30 00 00 0f 1f 44 00 00 4c 89 f7 e8 7b 23 36 09 e8 06 1e 32 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:ffffc90004897a08 EFLAGS: 00000286
RAX: c6837612147f9b00 RBX: ffff88805756d974 RCX: ffffffff91c95103
RDX: dffffc0000000000 RSI: ffffffff8aec0240 RDI: ffff888020fc5178
RBP: ffffc90004897a50 R08: dffffc0000000000 R09: ffffed1017307541
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff888020fc3b80
R13: 1ffff110173076eb R14: ffff8880b983aa00 R15: ffff8880b983b758
FS:  0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b32b2a000 CR3: 00000000553eb000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 </IRQ>
 <TASK>
 context_switch kernel/sched/core.c:5248 [inline]
 __schedule+0x1435/0x4550 kernel/sched/core.c:6558
 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6870
 irqentry_exit+0x53/0x80 kernel/entry/common.c:439
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:653
RIP: 0010:check_region_inline mm/kasan/generic.c:169 [inline]
RIP: 0010:kasan_check_range+0x8/0x290 mm/kasan/generic.c:189
Code: c4 a9 08 31 c0 c3 0f 0b b8 ea ff ff ff c3 0f 0b b8 ea ff ff ff c3 cc cc cc cc cc cc cc cc cc cc cc cc 55 41 57 41 56 53 b0 01 <48> 85 f6 0f 84 9a 01 00 00 48 89 fd 48 01 f5 0f 82 5a 02 00 00 48
RSP: 0018:ffffc90004897da0 EFLAGS: 00000246
RAX: 0000000000000001 RBX: 1ffff110041f8770 RCX: ffffffff8a939aa6
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff888020fc3b80
RBP: ffff888020b7aa68 R08: dffffc0000000000 R09: ffffed1017307541
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff888020fc3b80
R13: dffffc0000000000 R14: ffff888020fc4df8 R15: dffffc0000000000
 instrument_atomic_read include/linux/instrumented.h:72 [inline]
 _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
 test_ti_thread_flag include/linux/thread_info.h:118 [inline]
 need_resched include/linux/sched.h:2231 [inline]
 schedule+0xd6/0x180 kernel/sched/core.c:6636
 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:308
 </TASK>

Crashes (6):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/06/19 16:45 linux-6.1.y eb44d83053d6 41b7e219 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in worker_thread
2024/06/19 12:07 linux-6.1.y eb44d83053d6 41b7e219 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in worker_thread
2024/06/13 09:23 linux-6.1.y ae9f2a70d69e 2aa5052f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in worker_thread
2024/06/11 01:28 linux-6.1.y 88690811da69 048c640a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in worker_thread
2024/06/06 22:15 linux-6.1.y 88690811da69 121701b6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in worker_thread
2024/05/20 10:23 linux-6.1.y 4078fa637fcd c0f1611a .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.