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INFO: rcu detected stall in preempt_count_sub

Status: auto-closed as invalid on 2020/04/07 03:55
Subsystems: mm
[Documentation on labels]
First crash: 1661d, last: 1541d
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in preempt_count_sub (2) kernel 1 1202d 1202d 0/26 auto-closed as invalid on 2021/03/11 15:56

Sample crash report:
rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-...!: (10500 ticks this GP) idle=396/1/0x4000000000000004 softirq=369946/369946 fqs=71 
	(t=10500 jiffies g=424381 q=530)
NMI backtrace for cpu 1
CPU: 1 PID: 7710 Comm: syz-executor.0 Not tainted 5.4.0-rc3+ #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+0x172/0x1f0 lib/dump_stack.c:113
 nmi_cpu_backtrace.cold+0x70/0xb2 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x23b/0x28b lib/nmi_backtrace.c:62
 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38
 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline]
 rcu_dump_cpu_stacks+0x183/0x1cf kernel/rcu/tree_stall.h:254
 print_cpu_stall kernel/rcu/tree_stall.h:455 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:529 [inline]
 rcu_pending kernel/rcu/tree.c:2795 [inline]
 rcu_sched_clock_irq.cold+0x4fd/0xc12 kernel/rcu/tree.c:2244
 update_process_times+0x2d/0x70 kernel/time/timer.c:1726
 tick_sched_handle+0xa2/0x190 kernel/time/tick-sched.c:167
 tick_sched_timer+0x53/0x140 kernel/time/tick-sched.c:1299
 __run_hrtimer kernel/time/hrtimer.c:1514 [inline]
 __hrtimer_run_queues+0x364/0xe40 kernel/time/hrtimer.c:1576
 hrtimer_interrupt+0x314/0x770 kernel/time/hrtimer.c:1638
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1110 [inline]
 smp_apic_timer_interrupt+0x160/0x610 arch/x86/kernel/apic/apic.c:1135
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:830
RIP: 0010:preempt_count_sub+0x18/0x150 kernel/sched/core.c:3805
Code: 00 8b 4d d0 e9 3a fe ff ff 66 0f 1f 84 00 00 00 00 00 48 c7 c0 20 c1 ae 8a 55 48 ba 00 00 00 00 00 fc ff df 48 89 c1 48 89 e5 <53> 83 e0 07 48 c1 e9 03 83 c0 03 89 fb 0f b6 14 11 38 d0 7c 08 84
RSP: 0018:ffff8880ae909dc0 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13
RAX: ffffffff8aaec120 RBX: ffffffff85d548b0 RCX: ffffffff8aaec120
RDX: dffffc0000000000 RSI: 0000000000000002 RDI: 0000000000000001
RBP: ffff8880ae909dc0 R08: ffff8880256b0500 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff8880ae924c00
R13: ffff888094a9ab48 R14: ffff8880ae924c00 R15: dffffc0000000000
 __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline]
 _raw_spin_unlock_irq+0x5e/0x90 kernel/locking/spinlock.c:199
 expire_timers kernel/time/timer.c:1448 [inline]
 __run_timers kernel/time/timer.c:1773 [inline]
 __run_timers kernel/time/timer.c:1740 [inline]
 run_timer_softirq+0x6b1/0x1790 kernel/time/timer.c:1786
 __do_softirq+0x262/0x98c kernel/softirq.c:292
 invoke_softirq kernel/softirq.c:373 [inline]
 irq_exit+0x19b/0x1e0 kernel/softirq.c:413
 exiting_irq arch/x86/include/asm/apic.h:536 [inline]
 smp_apic_timer_interrupt+0x1a3/0x610 arch/x86/kernel/apic/apic.c:1137
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:830
 </IRQ>
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x54/0x90 kernel/locking/spinlock.c:199
Code: c0 70 1e f3 88 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 75 33 48 83 3d 95 2f a5 01 00 74 20 fb 66 0f 1f 44 00 00 <bf> 01 00 00 00 e8 12 24 01 fa 65 8b 05 13 0f b4 78 85 c0 74 06 41
RSP: 0018:ffff88801495f528 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13
RAX: 1ffffffff11e63ce RBX: ffff8880256b0500 RCX: 0000000000000000
RDX: dffffc0000000000 RSI: 0000000000000006 RDI: ffff8880256b0d94
RBP: ffff88801495f530 R08: ffff8880256b0500 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff8880ae934d00
R13: ffff88809570e340 R14: 0000000000000000 R15: 0000000000000001
 finish_lock_switch kernel/sched/core.c:3123 [inline]
 finish_task_switch+0x147/0x750 kernel/sched/core.c:3223
 context_switch kernel/sched/core.c:3387 [inline]
 __schedule+0x957/0x1e70 kernel/sched/core.c:4069
 preempt_schedule_common+0x4f/0xe0 kernel/sched/core.c:4217
 preempt_schedule+0x4b/0x60 kernel/sched/core.c:4242
 ___preempt_schedule+0x16/0x20 arch/x86/entry/thunk_64.S:50
 __raw_spin_unlock include/linux/spinlock_api_smp.h:152 [inline]
 _raw_spin_unlock+0x41/0x50 kernel/locking/spinlock.c:183
 spin_unlock include/linux/spinlock.h:378 [inline]
 zap_pte_range mm/memory.c:1118 [inline]
 zap_pmd_range mm/memory.c:1166 [inline]
 zap_pud_range mm/memory.c:1195 [inline]
 zap_p4d_range mm/memory.c:1216 [inline]
 unmap_page_range+0x105d/0x25f0 mm/memory.c:1237
 unmap_single_vma+0x19d/0x300 mm/memory.c:1282
 unmap_vmas+0x189/0x300 mm/memory.c:1314
 exit_mmap+0x2ba/0x530 mm/mmap.c:3161
 __mmput kernel/fork.c:1079 [inline]
 mmput+0x179/0x4d0 kernel/fork.c:1100
 exit_mm kernel/exit.c:485 [inline]
 do_exit+0x823/0x2e60 kernel/exit.c:804
 do_group_exit+0x135/0x360 kernel/exit.c:921
 get_signal+0x47c/0x2500 kernel/signal.c:2734
 do_signal+0x87/0x1700 arch/x86/kernel/signal.c:815
 exit_to_usermode_loop+0x286/0x380 arch/x86/entry/common.c:159
 prepare_exit_to_usermode arch/x86/entry/common.c:194 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:274 [inline]
 do_syscall_64+0x65f/0x760 arch/x86/entry/common.c:300
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x459a59
Code: fd b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f10b7a89cf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 000000000075bf28 RCX: 0000000000459a59
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000075bf28
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000075bf2c
R13: 0000000000a6fb7f R14: 00007f10b7a8a9c0 R15: 000000000075bf2c

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/10/19 04:27 upstream b9959c7a347d 8c88c9c1 .config console log report ci-upstream-kasan-gce
2019/09/10 10:59 upstream 56037cadf604 a60cb4cd .config console log report ci-upstream-kasan-gce-selinux-root
2020/01/08 03:51 linux-next 264673852033 6738e0b3 .config console log report ci-upstream-linux-next-kasan-gce-root
* Struck through repros no longer work on HEAD.