RAX: ffffffffffffffda RBX: 00007fd9bf18b6d4 RCX: 0000000000410dc1 RDX: 00007fd9bf18abdf RSI: 0000000000000002 RDI: 00007fd9bf18abd0 RBP: 00000000009300a0 R08: 0000000000000000 R09: 000000000000000f R10: 0000000000000004 R11: 0000000000000293 R12: 0000000000000004 R13: 00000000004d6b70 R14: 00000000004ca09a R15: 0000000000000000 rcu: INFO: rcu_sched self-detected stall on CPU rcu: 1-...!: (1 ticks this GP) idle=a86/1/0x4000000000000002 softirq=55911/55911 fqs=0 rcu: (t=111999 jiffies g=108637 q=251) rcu: rcu_sched kthread starved for 111999 jiffies! g108637 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0 rcu: RCU grace-period kthread stack dump: rcu_sched R running task 23480 10 2 0x80000000 Call Trace: context_switch kernel/sched/core.c:2825 [inline] __schedule+0x87c/0x1df0 kernel/sched/core.c:3473 schedule+0xfb/0x450 kernel/sched/core.c:3517 schedule_timeout+0x140/0x260 kernel/time/timer.c:1804 rcu_gp_kthread+0x743/0x1d20 kernel/rcu/tree.c:2194 kthread+0x35a/0x420 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:415 NMI backtrace for cpu 1 CPU: 1 PID: 4474 Comm: syz-fuzzer Not tainted 4.19.0-rc1-next-20180828+ #49 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+0x1c9/0x2b4 lib/dump_stack.c:113 nmi_cpu_backtrace.cold.3+0x48/0x88 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x151/0x192 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:162 [inline] rcu_dump_cpu_stacks+0x175/0x1c2 kernel/rcu/tree.c:1340 print_cpu_stall.cold.78+0x2fb/0x59c kernel/rcu/tree.c:1478 check_cpu_stall kernel/rcu/tree.c:1550 [inline] __rcu_pending kernel/rcu/tree.c:3276 [inline] rcu_pending kernel/rcu/tree.c:3319 [inline] rcu_check_callbacks+0xd4a/0x15a0 kernel/rcu/tree.c:2665 update_process_times+0x2d/0x70 kernel/time/timer.c:1636 tick_sched_handle+0x9f/0x180 kernel/time/tick-sched.c:164 tick_sched_timer+0x45/0x130 kernel/time/tick-sched.c:1274 __run_hrtimer kernel/time/hrtimer.c:1398 [inline] __hrtimer_run_queues+0x3eb/0xff0 kernel/time/hrtimer.c:1460 hrtimer_interrupt+0x2f3/0x750 kernel/time/hrtimer.c:1518 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1029 [inline] smp_apic_timer_interrupt+0x16d/0x6a0 arch/x86/kernel/apic/apic.c:1054 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:867 RIP: 0010:__read_once_size include/linux/compiler.h:188 [inline] RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:31 [inline] RIP: 0010:atomic_read include/asm-generic/atomic-instrumented.h:22 [inline] RIP: 0010:virt_spin_lock arch/x86/include/asm/qspinlock.h:65 [inline] RIP: 0010:native_queued_spin_lock_slowpath+0x1a2/0x1220 kernel/locking/qspinlock.c:305 Code: ff 4d 01 f4 be 04 00 00 00 4c 89 ff e8 67 8d 5b 00 4c 89 f8 41 c6 04 24 04 48 c1 e8 03 42 0f b6 04 30 38 85 f0 fb ff ff 7c 08 <84> c0 0f 85 29 0b 00 00 41 0f b6 34 24 45 8b 2f 40 84 f6 74 0a 40 RSP: 0000:ffff8801abdf71a8 EFLAGS: 00000206 ORIG_RAX: ffffffffffffff13 RAX: 0000000000000000 RBX: ffff8801abdf75b0 RCX: ffffffff81603bd9 RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff8801b0e74000 RBP: ffff8801abdf75d8 R08: ffffed00361ce801 R09: ffffed00361ce800 R10: ffffed00361ce800 R11: ffff8801b0e74003 R12: ffffed00357bee96 R13: 0000000000000001 R14: dffffc0000000000 R15: ffff8801b0e74000 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:679 [inline] queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:32 [inline] queued_spin_lock include/asm-generic/qspinlock.h:88 [inline] do_raw_spin_lock+0x1a7/0x200 kernel/locking/spinlock_debug.c:113 __raw_spin_lock include/linux/spinlock_api_smp.h:143 [inline] _raw_spin_lock+0x32/0x40 kernel/locking/spinlock.c:144 spin_lock include/linux/spinlock.h:329 [inline] wp_page_copy+0x500/0x12c0 mm/memory.c:2524 do_wp_page+0x875/0x1800 mm/memory.c:2793 handle_pte_fault mm/memory.c:3999 [inline] __handle_mm_fault+0x2931/0x4350 mm/memory.c:4107 handle_mm_fault+0x53e/0xc80 mm/memory.c:4144 __do_page_fault+0x620/0xe50 arch/x86/mm/fault.c:1395 do_page_fault+0xf6/0x7a4 arch/x86/mm/fault.c:1470 page_fault+0x1e/0x30 arch/x86/entry/entry_64.S:1164 RIP: 0033:0x41e331 Code: 0f 95 c7 44 89 c9 e9 ec fe ff ff 8b 0d 34 47 06 01 85 c9 7e 09 48 8b 4b 30 49 39 c8 73 42 84 07 41 0f b6 0c 31 44 84 d1 75 2c 44 08 17 0f b6 4b 62 f6 c1 01 0f 84 04 ff ff ff 48 8b 44 24 60 RSP: 002b:000000c420155828 EFLAGS: 00010246 RAX: 000000c42f0ae4c0 RBX: 00007f2db1af4098 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 00007f2da8a5ae90 RDI: 00007f2da8a5ae92 RBP: 000000c420155848 R08: 0000000000000013 R09: 0000000000000002 R10: 0000000000000008 R11: 0000000000020414 R12: 0000000000b7cde0 R13: 0000000000b241a8 R14: 000000c435123b78 R15: 0000000000000000