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INFO: rcu detected stall in check_preemption_disabled

Status: auto-closed as invalid on 2021/03/07 11:58
Subsystems: kernel
[Documentation on labels]
First crash: 1919d, last: 1919d
▶ ▼ Similar bugs (3)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in check_preemption_disabled (3) kernel 1 1 104d 104d 0/29 auto-obsoleted due to no activity on 2026/02/24 08:39
linux-4.19 INFO: rcu detected stall in check_preemption_disabled 1 2 2162d 2196d 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 593d 593d 0/29 auto-obsoleted due to no activity on 2024/10/23 19:46

Sample crash report:
rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-...!: (9811 ticks this GP) idle=52e/1/0x4000000000000000 softirq=19950/19953 fqs=69 
	(t=10501 jiffies g=24257 q=158)
rcu: rcu_preempt kthread starved for 9933 jiffies! g24257 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:29112 pid:   11 ppid:     2 flags:0x00004000
Call Trace:
 context_switch kernel/sched/core.c:3779 [inline]
 __schedule+0x893/0x2130 kernel/sched/core.c:4528
 schedule+0xcf/0x270 kernel/sched/core.c:4606
 schedule_timeout+0x148/0x250 kernel/time/timer.c:1871
 rcu_gp_fqs_loop kernel/rcu/tree.c:1925 [inline]
 rcu_gp_kthread+0xb4c/0x1c90 kernel/rcu/tree.c:2099
 kthread+0x3b1/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296
NMI backtrace for cpu 1
CPU: 1 PID: 12799 Comm: syz-executor.3 Not tainted 5.10.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x107/0x163 lib/dump_stack.c:118
 nmi_cpu_backtrace.cold+0x44/0xd7 lib/nmi_backtrace.c:105
 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline]
 rcu_dump_cpu_stacks+0x1e3/0x21e kernel/rcu/tree_stall.h:331
 print_cpu_stall kernel/rcu/tree_stall.h:563 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:637 [inline]
 rcu_pending kernel/rcu/tree.c:3694 [inline]
 rcu_sched_clock_irq.cold+0x472/0xee8 kernel/rcu/tree.c:2567
 update_process_times+0x77/0xd0 kernel/time/timer.c:1709
 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:176
 tick_sched_timer+0x1d1/0x2a0 kernel/time/tick-sched.c:1328
 __run_hrtimer kernel/time/hrtimer.c:1519 [inline]
 __hrtimer_run_queues+0x1ce/0xea0 kernel/time/hrtimer.c:1583
 hrtimer_interrupt+0x334/0x940 kernel/time/hrtimer.c:1645
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1080 [inline]
 __sysvec_apic_timer_interrupt+0x146/0x540 arch/x86/kernel/apic/apic.c:1097
 run_sysvec_on_irqstack_cond arch/x86/include/asm/irq_stack.h:91 [inline]
 sysvec_apic_timer_interrupt+0x48/0x100 arch/x86/kernel/apic/apic.c:1091
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:631
RIP: 0010:check_preemption_disabled+0x7/0x130 lib/smp_processor_id.c:13
Code: 4c 07 04 31 ff 89 de 0f 1f 44 00 00 85 db 75 ae 0f 1f 44 00 00 41 bc 01 00 00 00 e8 23 1d ce fa eb 9f cc 41 56 41 55 49 89 f5 <41> 54 55 48 89 fd 53 0f 1f 44 00 00 65 44 8b 25 35 02 1c 77 65 8b
RSP: 0018:ffffc90000d90de8 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffffffff816017e9
RDX: 0000000000000001 RSI: ffffffff899d9200 RDI: ffffffff899d9240
RBP: ffff888066f05838 R08: 0000000000000000 R09: ffffffff8cecae0f
R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000001
R13: ffffffff899d9200 R14: ffffffff850f2f50 R15: dffffc0000000000
 rcu_lockdep_current_cpu_online kernel/rcu/tree.c:1150 [inline]
 rcu_lockdep_current_cpu_online+0x2d/0x120 kernel/rcu/tree.c:1141
 rcu_read_lock_held_common kernel/rcu/update.c:110 [inline]
 rcu_read_lock_held_common kernel/rcu/update.c:100 [inline]
 rcu_read_lock_sched_held+0x25/0x70 kernel/rcu/update.c:121
 trace_hrtimer_expire_entry include/trace/events/timer.h:232 [inline]
 __run_hrtimer kernel/time/hrtimer.c:1516 [inline]
 __hrtimer_run_queues+0xcd2/0xea0 kernel/time/hrtimer.c:1583
 hrtimer_run_softirq+0x17b/0x360 kernel/time/hrtimer.c:1600
 __do_softirq+0x2a0/0x9f6 kernel/softirq.c:298
 asm_call_irq_on_stack+0xf/0x20
 </IRQ>
 __run_on_irqstack arch/x86/include/asm/irq_stack.h:26 [inline]
 run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:77 [inline]
 do_softirq_own_stack+0xaa/0xd0 arch/x86/kernel/irq_64.c:77
 invoke_softirq kernel/softirq.c:393 [inline]
 __irq_exit_rcu kernel/softirq.c:423 [inline]
 irq_exit_rcu+0x132/0x200 kernel/softirq.c:435
 sysvec_apic_timer_interrupt+0x4d/0x100 arch/x86/kernel/apic/apic.c:1091
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:631
RIP: 0010:lock_release+0x3d5/0x710 kernel/locking/lockdep.c:5445
Code: 15 02 00 00 48 c7 c7 40 5f 4b 89 e8 c5 6b 8f 07 b8 ff ff ff ff 65 0f c1 05 58 d8 ab 7e 83 f8 01 0f 85 67 01 00 00 ff 34 24 9d <48> b8 00 00 00 00 00 fc ff df 48 01 c5 48 c7 45 00 00 00 00 00 c7
RSP: 0018:ffffc900021ff6c0 EFLAGS: 00000246
RAX: 0000000000000001 RBX: ffffffffffffffff RCX: ffffc900021ff710
RDX: 1ffff1100362faf9 RSI: 0000000000000001 RDI: 0000000000000000
RBP: 1ffff9200043feda R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000001 R14: ffff88801b17d7d0 R15: ffff88801b17cec0
 __raw_spin_unlock include/linux/spinlock_api_smp.h:150 [inline]
 _raw_spin_unlock+0x12/0x40 kernel/locking/spinlock.c:183
 spin_unlock include/linux/spinlock.h:394 [inline]
 zap_pte_range mm/memory.c:1309 [inline]
 zap_pmd_range mm/memory.c:1357 [inline]
 zap_pud_range mm/memory.c:1386 [inline]
 zap_p4d_range mm/memory.c:1407 [inline]
 unmap_page_range+0xf98/0x2640 mm/memory.c:1428
 unmap_single_vma+0x198/0x300 mm/memory.c:1473
 unmap_vmas+0x168/0x2e0 mm/memory.c:1505
 exit_mmap+0x2b1/0x530 mm/mmap.c:3220
 __mmput+0x122/0x470 kernel/fork.c:1079
 mmput+0x53/0x60 kernel/fork.c:1100
 exit_mm kernel/exit.c:486 [inline]
 do_exit+0xa72/0x29b0 kernel/exit.c:796
 do_group_exit+0x125/0x310 kernel/exit.c:906
 get_signal+0x42a/0x1f10 kernel/signal.c:2758
 arch_do_signal+0x82/0x2390 arch/x86/kernel/signal.c:811
 exit_to_user_mode_loop kernel/entry/common.c:161 [inline]
 exit_to_user_mode_prepare+0x100/0x1a0 kernel/entry/common.c:191
 syscall_exit_to_user_mode+0x38/0x260 kernel/entry/common.c:266
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45e0f9
Code: Unable to access opcode bytes at RIP 0x45e0cf.
RSP: 002b:00007f13a0ddacf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 000000000119bf88 RCX: 000000000045e0f9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000119bf88
RBP: 000000000119bf80 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000119bf8c
R13: 00007fff1b888c0f R14: 00007f13a0ddb9c0 R15: 000000000119bf8c

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/12/07 11:50 upstream 0477e9288185 1190297f .config console log report info ci-upstream-kasan-gce-root
* Struck through repros no longer work on HEAD.