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INFO: rcu detected stall in kauditd_thread (4)

Status: upstream: reported on 2025/06/04 05:49
Reported-by: syzbot+8decb3dadf4949bef15f@syzkaller.appspotmail.com
First crash: 12d, last: 12d
▶ ▼ Similar bugs (9)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 INFO: rcu detected stall in kauditd_thread (3) 1 230d 230d 0/3 auto-obsoleted due to no activity on 2025/02/06 22:50
linux-5.15 INFO: rcu detected stall in kauditd_thread (2) 1 220d 220d 0/3 auto-obsoleted due to no activity on 2025/02/16 01:15
upstream INFO: rcu detected stall in kauditd_thread (3) kernel 2 572d 605d 0/28 auto-obsoleted due to no activity on 2024/02/20 23:02
upstream INFO: rcu detected stall in kauditd_thread kernel 2 1241d 1296d 0/28 closed as invalid on 2022/02/08 10:00
linux-6.1 INFO: rcu detected stall in kauditd_thread (2) 3 447d 553d 0/3 auto-obsoleted due to no activity on 2024/07/04 19:28
upstream INFO: rcu detected stall in kauditd_thread (4) audit C error 31 12d 446d 0/28 upstream: reported C repro on 2024/03/27 18:39
linux-6.1 INFO: rcu detected stall in kauditd_thread 2 667d 753d 0/3 auto-obsoleted due to no activity on 2023/11/27 06:59
linux-5.15 INFO: rcu detected stall in kauditd_thread 2 542d 559d 0/3 auto-obsoleted due to no activity on 2024/03/31 22:45
android-5-15 BUG: soft lockup in kauditd_thread C error 5 277d 438d 0/2 auto-obsoleted due to no activity on 2024/12/21 07:08

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (1 GPs behind) idle=91b4/1/0x4000000000000000 softirq=54658/54659 fqs=106
	(detected by 0, t=10502 jiffies, g=84873, q=612 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 26 Comm: kauditd Not tainted 6.1.140-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:lock_release+0x57d/0x910 kernel/locking/lockdep.c:5685
Code: ff 65 0f c1 05 04 09 9f 7e 83 f8 01 75 75 48 c7 84 24 80 00 00 00 00 00 00 00 9c 8f 84 24 80 00 00 00 f6 84 24 81 00 00 00 02 <75> 75 f7 44 24 50 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45
RSP: 0018:ffffc900001e0ae0 EFLAGS: 00000046
RAX: 0000000000000001 RBX: b4f6a874e194f063 RCX: 9c43a10ff6a45800
RDX: 0000000000000002 RSI: ffffffff8a6c1180 RDI: ffffffff8abf1260
RBP: ffffc900001e0bf0 R08: dffffc0000000000 R09: fffffbfff1bfd006
R10: fffffbfff1bfd006 R11: 1ffffffff1bfd005 R12: ffff8880176c46b0
R13: dffffc0000000000 R14: ffff8880176c4650 R15: 1ffff9200003c168
FS:  0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c2cea3c CR3: 0000000069128000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:149 [inline]
 _raw_spin_unlock_irqrestore+0x6d/0x100 kernel/locking/spinlock.c:194
 debug_object_activate+0x2d7/0x490 lib/debugobjects.c:716
 debug_hrtimer_activate kernel/time/hrtimer.c:411 [inline]
 debug_activate kernel/time/hrtimer.c:466 [inline]
 enqueue_hrtimer+0x30/0x3f0 kernel/time/hrtimer.c:1075
 __run_hrtimer kernel/time/hrtimer.c:1708 [inline]
 __hrtimer_run_queues+0x642/0xc80 kernel/time/hrtimer.c:1755
 hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1817
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1107 [inline]
 __sysvec_apic_timer_interrupt+0x153/0x5a0 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:console_emit_next_record+0xab0/0xc90 kernel/printk/printk.c:2786
Code: f6 6d 1a 00 4d 85 ff 75 16 e8 ec 6d 1a 00 eb 15 e8 e5 6d 1a 00 e8 c0 c7 a8 08 4d 85 ff 74 ea e8 d6 6d 1a 00 fb 48 8b 5c 24 48 <48> c7 84 24 80 00 00 00 0e 36 e0 45 4a c7 04 2b 00 00 00 00 4a c7
RSP: 0018:ffffc90000a2f840 EFLAGS: 00000293
RAX: ffffffff8166693a RBX: 1ffff92000145f18 RCX: ffff8880176c3b80
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90000a2fa80 R08: dffffc0000000000 R09: fffffbfff2117049
R10: fffffbfff2117049 R11: 1ffffffff2117048 R12: ffffffff816666bd
R13: dffffc0000000000 R14: 0000000000000001 R15: 0000000000000200
 console_flush_all kernel/printk/printk.c:-1 [inline]
 console_unlock+0x223/0x630 kernel/printk/printk.c:2906
 vprintk_emit+0x489/0x680 kernel/printk/printk.c:2303
 _printk+0xcc/0x110 kernel/printk/printk.c:2328
 kauditd_printk_skb kernel/audit.c:547 [inline]
 kauditd_hold_skb+0x1c2/0x210 kernel/audit.c:582
 kauditd_send_queue+0x290/0x2e0 kernel/audit.c:767
 kauditd_thread+0x70e/0x980 kernel/audit.c:891
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
rcu: rcu_preempt kthread starved for 10288 jiffies! g84873 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:26432 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10e9/0x40d0 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:
CPU: 0 PID: 13903 Comm: kworker/u4:53 Not tainted 6.1.140-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:csd_lock_wait kernel/smp.c:424 [inline]
RIP: 0010:smp_call_function_many_cond+0xe7b/0x1270 kernel/smp.c:998
Code: 00 00 00 41 8b 1f 89 de 83 e6 01 31 ff e8 6d e9 0a 00 83 e3 01 48 bb 00 00 00 00 00 fc ff df 75 07 e8 f9 e5 0a 00 eb 37 f3 90 <41> 0f b6 04 1c 84 c0 75 10 41 f7 07 01 00 00 00 74 1e e8 de e5 0a
RSP: 0018:ffffc90004c3f800 EFLAGS: 00000293
RAX: ffffffff8175f132 RBX: dffffc0000000000 RCX: ffff8880463b1dc0
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90004c3f960 R08: dffffc0000000000 R09: fffffbfff2117049
R10: fffffbfff2117049 R11: 1ffffffff2117048 R12: 1ffff110171e81b9
R13: ffff8880b8e3bb00 R14: 0000000000000001 R15: ffff8880b8f40dc8
FS:  0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f87024e5000 CR3: 000000000c68e000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 on_each_cpu_cond_mask+0x3b/0x80 kernel/smp.c:1166
 on_each_cpu include/linux/smp.h:71 [inline]
 text_poke_sync arch/x86/kernel/alternative.c:1574 [inline]
 text_poke_bp_batch+0x71b/0x7d0 arch/x86/kernel/alternative.c:-1
 text_poke_flush arch/x86/kernel/alternative.c:1965 [inline]
 text_poke_finish+0x16/0x30 arch/x86/kernel/alternative.c:1972
 arch_jump_label_transform_apply+0x13/0x20 arch/x86/kernel/jump_label.c:146
 static_key_enable_cpuslocked+0x11f/0x240 kernel/jump_label.c:207
 static_key_enable+0x16/0x20 kernel/jump_label.c:220
 toggle_allocation_gate+0xb4/0x430 mm/kfence/core.c:805
 process_one_work+0x898/0x1160 kernel/workqueue.c:2292
 worker_thread+0xaa2/0x1250 kernel/workqueue.c:2439
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
watchdog: BUG: soft lockup - CPU#0 stuck for 233s! [kworker/u4:53:13903]
Modules linked in:
irq event stamp: 231678
hardirqs last  enabled at (231677): [<ffffffff8a200d46>] asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
hardirqs last disabled at (231678): [<ffffffff8a0f2a3a>] sysvec_apic_timer_interrupt+0xa/0xc0 arch/x86/kernel/apic/apic.c:1118
softirqs last  enabled at (181424): [<ffffffff814e6c7f>] __do_softirq kernel/softirq.c:612 [inline]
softirqs last  enabled at (181424): [<ffffffff814e6c7f>] invoke_softirq kernel/softirq.c:452 [inline]
softirqs last  enabled at (181424): [<ffffffff814e6c7f>] __irq_exit_rcu+0x12f/0x220 kernel/softirq.c:661
softirqs last disabled at (181217): [<ffffffff814e6c7f>] __do_softirq kernel/softirq.c:612 [inline]
softirqs last disabled at (181217): [<ffffffff814e6c7f>] invoke_softirq kernel/softirq.c:452 [inline]
softirqs last disabled at (181217): [<ffffffff814e6c7f>] __irq_exit_rcu+0x12f/0x220 kernel/softirq.c:661
CPU: 0 PID: 13903 Comm: kworker/u4:53 Not tainted 6.1.140-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:csd_lock_wait kernel/smp.c:424 [inline]
RIP: 0010:smp_call_function_many_cond+0xe7b/0x1270 kernel/smp.c:998
Code: 00 00 00 41 8b 1f 89 de 83 e6 01 31 ff e8 6d e9 0a 00 83 e3 01 48 bb 00 00 00 00 00 fc ff df 75 07 e8 f9 e5 0a 00 eb 37 f3 90 <41> 0f b6 04 1c 84 c0 75 10 41 f7 07 01 00 00 00 74 1e e8 de e5 0a
RSP: 0018:ffffc90004c3f800 EFLAGS: 00000293
RAX: ffffffff8175f132 RBX: dffffc0000000000 RCX: ffff8880463b1dc0
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90004c3f960 R08: dffffc0000000000 R09: fffffbfff2117049
R10: fffffbfff2117049 R11: 1ffffffff2117048 R12: 1ffff110171e81b9
R13: ffff8880b8e3bb00 R14: 0000000000000001 R15: ffff8880b8f40dc8
FS:  0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f87024e5000 CR3: 000000000c68e000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 on_each_cpu_cond_mask+0x3b/0x80 kernel/smp.c:1166
 on_each_cpu include/linux/smp.h:71 [inline]
 text_poke_sync arch/x86/kernel/alternative.c:1574 [inline]
 text_poke_bp_batch+0x71b/0x7d0 arch/x86/kernel/alternative.c:-1
 text_poke_flush arch/x86/kernel/alternative.c:1965 [inline]
 text_poke_finish+0x16/0x30 arch/x86/kernel/alternative.c:1972
 arch_jump_label_transform_apply+0x13/0x20 arch/x86/kernel/jump_label.c:146
 static_key_enable_cpuslocked+0x11f/0x240 kernel/jump_label.c:207
 static_key_enable+0x16/0x20 kernel/jump_label.c:220
 toggle_allocation_gate+0xb4/0x430 mm/kfence/core.c:805
 process_one_work+0x898/0x1160 kernel/workqueue.c:2292
 worker_thread+0xaa2/0x1250 kernel/workqueue.c:2439
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 26 Comm: kauditd Not tainted 6.1.140-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:hlock_class kernel/locking/lockdep.c:228 [inline]
RIP: 0010:check_wait_context kernel/locking/lockdep.c:4748 [inline]
RIP: 0010:__lock_acquire+0x933/0x7c50 kernel/locking/lockdep.c:4999
Code: 89 c6 41 81 e6 ff 1f 00 00 c1 e8 03 25 f8 03 00 00 48 8d b8 40 82 8b 90 be 08 00 00 00 e8 a5 56 6f 00 4c 0f a3 35 3d 8a 28 0f <73> 1a 4b 8d 04 76 c1 e0 06 4c 8d b0 00 01 24 90 49 b8 00 00 00 00
RSP: 0018:ffffc900001e0860 EFLAGS: 00000057
RAX: 0000000000000001 RBX: 0000000000000001 RCX: ffffffff8162f7fb
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff908b8248
RBP: ffffc900001e0ab0 R08: dffffc0000000000 R09: fffffbfff211704a
R10: fffffbfff211704a R11: 1ffffffff2117049 R12: ffff8880176c46a8
R13: ffff8880176c4602 R14: 0000000000000062 R15: ffff8880176c46a8
FS:  0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c2cea3c CR3: 0000000069128000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 lock_acquire+0x1b4/0x490 kernel/locking/lockdep.c:5662
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0xa4/0xf0 kernel/locking/spinlock.c:162
 debug_object_activate+0x6a/0x490 lib/debugobjects.c:698
 debug_hrtimer_activate kernel/time/hrtimer.c:411 [inline]
 debug_activate kernel/time/hrtimer.c:466 [inline]
 enqueue_hrtimer+0x30/0x3f0 kernel/time/hrtimer.c:1075
 __run_hrtimer kernel/time/hrtimer.c:1708 [inline]
 __hrtimer_run_queues+0x642/0xc80 kernel/time/hrtimer.c:1755
 hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1817
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1107 [inline]
 __sysvec_apic_timer_interrupt+0x153/0x5a0 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:console_emit_next_record+0xab0/0xc90 kernel/printk/printk.c:2786
Code: f6 6d 1a 00 4d 85 ff 75 16 e8 ec 6d 1a 00 eb 15 e8 e5 6d 1a 00 e8 c0 c7 a8 08 4d 85 ff 74 ea e8 d6 6d 1a 00 fb 48 8b 5c 24 48 <48> c7 84 24 80 00 00 00 0e 36 e0 45 4a c7 04 2b 00 00 00 00 4a c7
RSP: 0018:ffffc90000a2f840 EFLAGS: 00000293
RAX: ffffffff8166693a RBX: 1ffff92000145f18 RCX: ffff8880176c3b80
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90000a2fa80 R08: dffffc0000000000 R09: fffffbfff2117049
R10: fffffbfff2117049 R11: 1ffffffff2117048 R12: ffffffff816666bd
R13: dffffc0000000000 R14: 0000000000000001 R15: 0000000000000200
 console_flush_all kernel/printk/printk.c:-1 [inline]
 console_unlock+0x223/0x630 kernel/printk/printk.c:2906
 vprintk_emit+0x489/0x680 kernel/printk/printk.c:2303
 _printk+0xcc/0x110 kernel/printk/printk.c:2328
 kauditd_printk_skb kernel/audit.c:547 [inline]
 kauditd_hold_skb+0x1c2/0x210 kernel/audit.c:582
 kauditd_send_queue+0x290/0x2e0 kernel/audit.c:767
 kauditd_thread+0x70e/0x980 kernel/audit.c:891
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/06/04 05:48 linux-6.1.y da3c5173c55f a30356b7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in kauditd_thread
* Struck through repros no longer work on HEAD.