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INFO: rcu detected stall in check_preemption_disabled (3)

Status: auto-obsoleted due to no activity on 2026/02/24 08:39
Subsystems: kernel
[Documentation on labels]
First crash: 96d, last: 96d
▶ ▼ Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in check_preemption_disabled kernel 1 1 1911d 1911d 0/29 auto-closed as invalid on 2021/03/07 11:58
linux-4.19 INFO: rcu detected stall in check_preemption_disabled 1 2 2153d 2188d 0/1 auto-closed as invalid on 2020/08/07 05:10
upstream INFO: rcu detected stall in check_preemption_disabled (2) bpf trace 1 1 584d 584d 0/29 auto-obsoleted due to no activity on 2024/10/23 19:46
linux-4.14 BUG: soft lockup in check_preemption_disabled 1 1 1398d 1398d 0/1 auto-obsoleted due to no activity on 2022/08/31 17:10

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P16
rcu: 	(detected by 0, t=10502 jiffies, g=186125, q=20193 ncpus=2)
task:ktimers/0       state:R  running task     stack:20824 pid:16    tgid:16    ppid:2      task_flags:0x4208040 flags:0x00080000
Call Trace:
 <IRQ>
 sched_show_task+0x49d/0x630 kernel/sched/core.c:7901
 rcu_print_detail_task_stall_rnp kernel/rcu/tree_stall.h:292 [inline]
 print_other_cpu_stall+0xf78/0x1340 kernel/rcu/tree_stall.h:681
 check_cpu_stall kernel/rcu/tree_stall.h:857 [inline]
 rcu_pending kernel/rcu/tree.c:3671 [inline]
 rcu_sched_clock_irq+0xa47/0x11b0 kernel/rcu/tree.c:2706
 update_process_times+0x235/0x2d0 kernel/time/timer.c:2474
 tick_sched_handle kernel/time/tick-sched.c:276 [inline]
 tick_nohz_handler+0x39a/0x520 kernel/time/tick-sched.c:297
 __run_hrtimer kernel/time/hrtimer.c:1777 [inline]
 __hrtimer_run_queues+0x506/0xd40 kernel/time/hrtimer.c:1841
 hrtimer_interrupt+0x45d/0xa90 kernel/time/hrtimer.c:1903
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1041 [inline]
 __sysvec_apic_timer_interrupt+0x10b/0x410 arch/x86/kernel/apic/apic.c:1058
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline]
 sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1052
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:check_preemption_disabled+0x35/0x120 lib/smp_processor_id.c:53
Code: 48 8b 05 ce e4 e1 06 48 89 44 24 08 65 8b 05 d6 e4 e1 06 65 8b 0d cb e4 e1 06 f7 c1 ff ff ff 7f 74 23 65 48 8b 0d ab e4 e1 06 <48> 3b 4c 24 08 0f 85 cc 00 00 00 48 83 c4 10 5b 41 5e 41 5f 5d e9
RSP: 0018:ffffc90000157948 EFLAGS: 00000202
RAX: 0000000000000000 RBX: ffff88803765d4c0 RCX: 5fa81369ce852200
RDX: 0000000000000100 RSI: ffffffff8b3ddfc0 RDI: ffffffff8b3ddf80
RBP: ffffc90000157ae8 R08: 0000000000000000 R09: 0000000000000100
R10: dffffc0000000000 R11: fffffbfff1dac84f R12: ffff8880b8828280
R13: 0000000000000000 R14: 0000000000000001 R15: ffffffff88ddd9e0
 rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline]
 rcu_is_watching+0x15/0xb0 kernel/rcu/tree.c:751
 trace_hrtimer_expire_entry include/trace/events/timer.h:259 [inline]
 __run_hrtimer kernel/time/hrtimer.c:1774 [inline]
 __hrtimer_run_queues+0x49c/0xd40 kernel/time/hrtimer.c:1841
 hrtimer_run_softirq+0x1a3/0x2e0 kernel/time/hrtimer.c:1858
 handle_softirqs+0x22f/0x710 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 run_ktimerd+0xcf/0x190 kernel/softirq.c:1138
 smpboot_thread_fn+0x542/0xa60 kernel/smpboot.c:160
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g186125 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=107584
rcu: rcu_preempt kthread starved for 10502 jiffies! g186125 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:26384 pid:18    tgid:18    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5325 [inline]
 __schedule+0x16f3/0x4c20 kernel/sched/core.c:6929
 __schedule_loop kernel/sched/core.c:7011 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:7026
 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083
 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 16 Comm: ktimers/0 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:check_preemption_disabled+0x35/0x120 lib/smp_processor_id.c:53
Code: 48 8b 05 ce e4 e1 06 48 89 44 24 08 65 8b 05 d6 e4 e1 06 65 8b 0d cb e4 e1 06 f7 c1 ff ff ff 7f 74 23 65 48 8b 0d ab e4 e1 06 <48> 3b 4c 24 08 0f 85 cc 00 00 00 48 83 c4 10 5b 41 5e 41 5f 5d e9
RSP: 0018:ffffc90000157948 EFLAGS: 00000202
RAX: 0000000000000000 RBX: ffff88803765d4c0 RCX: 5fa81369ce852200
RDX: 0000000000000100 RSI: ffffffff8b3ddfc0 RDI: ffffffff8b3ddf80
RBP: ffffc90000157ae8 R08: 0000000000000000 R09: 0000000000000100
R10: dffffc0000000000 R11: fffffbfff1dac84f R12: ffff8880b8828280
R13: 0000000000000000 R14: 0000000000000001 R15: ffffffff88ddd9e0
FS:  0000000000000000(0000) GS:ffff888126df6000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2e32ad4005 CR3: 000000001c6f6000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline]
 rcu_is_watching+0x15/0xb0 kernel/rcu/tree.c:751
 trace_hrtimer_expire_entry include/trace/events/timer.h:259 [inline]
 __run_hrtimer kernel/time/hrtimer.c:1774 [inline]
 __hrtimer_run_queues+0x49c/0xd40 kernel/time/hrtimer.c:1841
 hrtimer_run_softirq+0x1a3/0x2e0 kernel/time/hrtimer.c:1858
 handle_softirqs+0x22f/0x710 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 run_ktimerd+0xcf/0x190 kernel/softirq.c:1138
 smpboot_thread_fn+0x542/0xa60 kernel/smpboot.c:160
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/11/26 08:33 upstream 30f09200cc4a 64219f15 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: rcu detected stall in check_preemption_disabled
* Struck through repros no longer work on HEAD.