rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-...!: (1 GPs behind) idle=68e/1/0x4000000000000004 softirq=124401/124404 fqs=11 rcu: (t=10502 jiffies g=148209 q=557) rcu: rcu_preempt kthread starved for 10480 jiffies! g148209 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1 rcu: RCU grace-period kthread stack dump: rcu_preempt R running task 29152 10 2 0x80000000 Call Trace: schedule+0x8d/0x1b0 kernel/sched/core.c:3559 schedule_timeout+0x4d1/0xf20 kernel/time/timer.c:1806 rcu_gp_kthread+0xcee/0x2060 kernel/rcu/tree.c:2202 kthread+0x34a/0x420 kernel/kthread.c:246 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 NMI backtrace for cpu 0 CPU: 0 PID: 31239 Comm: syz-executor.3 Not tainted 4.19.107-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+0x188/0x20d lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x63/0xa2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1a6/0x1eb lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline] rcu_dump_cpu_stacks+0x170/0x1bb kernel/rcu/tree.c:1340 print_cpu_stall kernel/rcu/tree.c:1478 [inline] check_cpu_stall kernel/rcu/tree.c:1550 [inline] __rcu_pending kernel/rcu/tree.c:3293 [inline] rcu_pending kernel/rcu/tree.c:3336 [inline] rcu_check_callbacks.cold+0x634/0xddc kernel/rcu/tree.c:2682 update_process_times+0x2a/0x70 kernel/time/timer.c:1638 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:168 tick_sched_timer+0x42/0x130 kernel/time/tick-sched.c:1278 __run_hrtimer kernel/time/hrtimer.c:1401 [inline] __hrtimer_run_queues+0x2fc/0xd50 kernel/time/hrtimer.c:1463 hrtimer_interrupt+0x312/0x770 kernel/time/hrtimer.c:1521 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1067 [inline] smp_apic_timer_interrupt+0x10c/0x550 arch/x86/kernel/apic/apic.c:1092 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:893 RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:789 [inline] RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:160 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0x91/0xe0 kernel/locking/spinlock.c:184 Code: 48 c7 c0 88 56 b2 88 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 75 37 48 83 3d fe 5d 92 01 00 74 22 48 89 df 57 9d <0f> 1f 44 00 00 bf 01 00 00 00 e8 c0 a1 26 fa 65 8b 05 29 f5 e1 78 RSP: 0018:ffff8880ae607c50 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13 RAX: 1ffffffff1164ad1 RBX: 0000000000000282 RCX: 1ffff110025901dc RDX: dffffc0000000000 RSI: ffff888012c80ec0 RDI: 0000000000000282 RBP: ffff8880ae623a00 R08: ffff888012c80640 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 1ffff11015cc0f95 R14: 0000000000000000 R15: ffff8880ae623a00 __mod_timer kernel/time/timer.c:1059 [inline] mod_timer+0x530/0xfb0 kernel/time/timer.c:1102 call_timer_fn+0x177/0x700 kernel/time/timer.c:1326 expire_timers kernel/time/timer.c:1363 [inline] __run_timers kernel/time/timer.c:1684 [inline] __run_timers kernel/time/timer.c:1652 [inline] run_timer_softirq+0x5d0/0x1540 kernel/time/timer.c:1697 __do_softirq+0x26c/0x93c kernel/softirq.c:292 invoke_softirq kernel/softirq.c:372 [inline] irq_exit+0x17b/0x1c0 kernel/softirq.c:412 exiting_irq arch/x86/include/asm/apic.h:544 [inline] smp_apic_timer_interrupt+0x136/0x550 arch/x86/kernel/apic/apic.c:1094 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:893 RIP: 0010:get_current arch/x86/include/asm/current.h:15 [inline] RIP: 0010:syscall_return_slowpath arch/x86/entry/common.c:252 [inline] RIP: 0010:do_syscall_64+0x11c/0x620 arch/x86/entry/common.c:296 Code: ff 14 dd 40 46 60 87 48 8d 7d 50 48 ba 00 00 00 00 00 fc ff df 48 89 f9 48 c1 e9 03 80 3c 11 00 0f 85 be 04 00 00 48 89 45 50 8f fd 66 00 48 b8 00 00 00 00 00 fc ff df 65 48 8b 1c 25 40 ee RSP: 0018:ffff888060afff28 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: 0000000000000000 RBX: 0000000000000048 RCX: 1ffff1100c15fff5 RDX: dffffc0000000000 RSI: ffffffff81ab5a0c RDI: ffff888060afffa8 RBP: ffff888060afff58 R08: ffff888012c80640 R09: ffffed10148a1a5f R10: ffffed10148a1a5e R11: ffff8880a450d2f7 R12: 0000000000000000 R13: ffffffff88b25698 R14: 0000000000000000 R15: 0000000000000000 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c479 Code: ad b6 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 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f68f925dc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000048 RAX: 0000000000000000 RBX: 00007f68f925e6d4 RCX: 000000000045c479 RDX: 0000000000042000 RSI: 0000000000000004 RDI: 0000000000000004 RBP: 000000000076bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000000c5 R14: 00000000004c3122 R15: 000000000076bf2c