rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-....: (10499 ticks this GP) idle=4ca/1/0x4000000000000000 softirq=78234/78234 fqs=5234 (t=10500 jiffies g=140781 q=161902) NMI backtrace for cpu 0 CPU: 0 PID: 5540 Comm: syz-executor.4 Not tainted 5.9.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x18f/0x20d lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x70/0xb1 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1b3/0x223 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline] rcu_dump_cpu_stacks+0x194/0x1cf kernel/rcu/tree_stall.h:318 print_cpu_stall kernel/rcu/tree_stall.h:551 [inline] check_cpu_stall kernel/rcu/tree_stall.h:625 [inline] rcu_pending kernel/rcu/tree.c:3637 [inline] rcu_sched_clock_irq.cold+0x5b3/0xccd kernel/rcu/tree.c:2519 update_process_times+0x25/0xa0 kernel/time/timer.c:1710 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:1524 [inline] __hrtimer_run_queues+0x1d5/0xfc0 kernel/time/hrtimer.c:1588 hrtimer_interrupt+0x32a/0x930 kernel/time/hrtimer.c:1650 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1080 [inline] __sysvec_apic_timer_interrupt+0x142/0x5e0 arch/x86/kernel/apic/apic.c:1097 run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:50 [inline] sysvec_apic_timer_interrupt+0x4c/0xf0 arch/x86/kernel/apic/apic.c:1091 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:581 RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:770 [inline] RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:160 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0x8c/0xe0 kernel/locking/spinlock.c:191 Code: 48 c7 c0 c8 3b b6 89 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 75 37 48 83 3d f3 ef bf 01 00 74 22 48 89 df 57 9d <0f> 1f 44 00 00 bf 01 00 00 00 e8 95 67 59 f9 65 8b 05 8e b2 0b 78 RSP: 0018:ffffc90000007bf0 EFLAGS: 00000286 RAX: 1ffffffff136c779 RBX: 0000000000000286 RCX: 0000000000000002 RDX: dffffc0000000000 RSI: 0000000000000000 RDI: 0000000000000286 RBP: ffff8880ae6255c0 R08: 0000000000000001 R09: ffffffff8c5f3aaf R10: fffffbfff18be755 R11: 0000000000000001 R12: 000000010000dca0 R13: ffff8880ae6255c0 R14: 0000000000000000 R15: 00000000ffffffff __mod_timer+0x825/0xd90 kernel/time/timer.c:1066 call_timer_fn+0x1ac/0x760 kernel/time/timer.c:1413 expire_timers kernel/time/timer.c:1458 [inline] __run_timers.part.0+0x67c/0xaa0 kernel/time/timer.c:1755 __run_timers kernel/time/timer.c:1736 [inline] run_timer_softirq+0xae/0x1a0 kernel/time/timer.c:1768 __do_softirq+0x2de/0xa24 kernel/softirq.c:298 asm_call_on_stack+0xf/0x20 arch/x86/entry/entry_64.S:706 __run_on_irqstack arch/x86/include/asm/irq_stack.h:22 [inline] run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:48 [inline] do_softirq_own_stack+0x9d/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+0x1f3/0x230 kernel/softirq.c:435 sysvec_apic_timer_interrupt+0x51/0xf0 arch/x86/kernel/apic/apic.c:1091 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:581 RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline] RIP: 0010:_raw_spin_unlock_irq+0x4b/0x80 kernel/locking/spinlock.c:199 Code: c0 d8 3b b6 89 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 75 31 48 83 3d 46 f6 bf 01 00 74 25 fb 66 0f 1f 44 00 00 01 00 00 00 e8 db 6d 59 f9 65 8b 05 d4 b8 0b 78 85 c0 74 02 5d RSP: 0018:ffffc900055e7978 EFLAGS: 00000286 RAX: 1ffffffff136c77b RBX: ffff888090894540 RCX: 0000000000000006 RDX: dffffc0000000000 RSI: 0000000000000000 RDI: ffffffff87f6456f RBP: ffff8880ae635e00 R08: 0000000000000001 R09: ffffffff8c5f3abf R10: fffffbfff18be757 R11: 0000000000000001 R12: ffff8880ae635e00 R13: ffff88809644e500 R14: ffff8880a8eee040 R15: 0000000000000402 finish_lock_switch kernel/sched/core.c:3517 [inline] finish_task_switch+0x147/0x750 kernel/sched/core.c:3617 context_switch kernel/sched/core.c:3781 [inline] __schedule+0x8ed/0x21e0 kernel/sched/core.c:4527 preempt_schedule_common+0x45/0xc0 kernel/sched/core.c:4683 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:40 smp_call_function_single+0x467/0x4f0 kernel/smp.c:384 task_function_call+0xd7/0x160 kernel/events/core.c:116 perf_install_in_context+0x2cb/0x550 kernel/events/core.c:2895 __do_sys_perf_event_open+0x1c31/0x2cb0 kernel/events/core.c:11992 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45d5b9 Code: 5d b4 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 2b b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f1cb2834c78 EFLAGS: 00000246 ORIG_RAX: 000000000000012a RAX: ffffffffffffffda RBX: 0000000000024780 RCX: 000000000045d5b9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000100 RBP: 000000000118d030 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffffffffffff R11: 0000000000000246 R12: 000000000118cfec R13: 00007ffe6db7bdbf R14: 00007f1cb28359c0 R15: 000000000118cfec