rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-...!: (1 GPs behind) idle=8d2/1/0x4000000000000002 softirq=10751/10754 fqs=2 (t=10500 jiffies g=6065 q=362) rcu: rcu_preempt kthread starved for 10496 jiffies! g6065 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1 rcu: RCU grace-period kthread stack dump: rcu_preempt R running task 29032 10 2 0x80004000 Call Trace: context_switch kernel/sched/core.c:3385 [inline] __schedule+0x9a0/0xcc0 kernel/sched/core.c:4081 schedule+0x181/0x210 kernel/sched/core.c:4155 schedule_timeout+0x14f/0x240 kernel/time/timer.c:1895 rcu_gp_fqs_loop kernel/rcu/tree.c:1661 [inline] rcu_gp_kthread+0xed8/0x1770 kernel/rcu/tree.c:1821 kthread+0x332/0x350 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 NMI backtrace for cpu 0 CPU: 0 PID: 8104 Comm: udevd Not tainted 5.4.0-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+0x1fb/0x318 lib/dump_stack.c:118 nmi_cpu_backtrace+0xaf/0x1a0 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x174/0x290 lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x10/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline] rcu_dump_cpu_stacks+0x15a/0x220 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:2827 [inline] rcu_sched_clock_irq+0xe25/0x1ad0 kernel/rcu/tree.c:2271 update_process_times+0x12d/0x180 kernel/time/timer.c:1726 tick_sched_handle kernel/time/tick-sched.c:167 [inline] tick_sched_timer+0x263/0x420 kernel/time/tick-sched.c:1310 __run_hrtimer kernel/time/hrtimer.c:1514 [inline] __hrtimer_run_queues+0x403/0x840 kernel/time/hrtimer.c:1576 hrtimer_interrupt+0x38c/0xda0 kernel/time/hrtimer.c:1638 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1110 [inline] smp_apic_timer_interrupt+0x109/0x280 arch/x86/kernel/apic/apic.c:1135 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829 RIP: 0010:__sanitizer_cov_trace_pc+0x48/0x50 kernel/kcov.c:112 Code: 80 13 00 00 83 fa 02 75 21 48 8b 91 88 13 00 00 48 8b 32 48 8d 7e 01 8b 89 84 13 00 00 48 39 cf 73 08 48 89 44 f2 08 48 89 3a 0f 1f 80 00 00 00 00 4c 8b 04 24 65 48 8b 04 25 c0 1d 02 00 65 RSP: 0018:ffffc90001e27780 EFLAGS: 00000293 ORIG_RAX: ffffffffffffff13 RAX: ffffffff81487433 RBX: 0000000000000000 RCX: ffff88808c92e3c0 RDX: 0000000000000000 RSI: 00000000fffffffc RDI: ffffea0002a214c0 RBP: ffffc90001e277a8 R08: 000000000003a768 R09: ffffed1015137287 R10: ffffed1015137287 R11: 0000000000000000 R12: dffffc0000000000 R13: dffffc0000000000 R14: 00000000fffffffc R15: ffff8880a89b9428 free_thread_stack+0x168/0x590 kernel/fork.c:280 release_task_stack kernel/fork.c:440 [inline] put_task_stack+0xa3/0x130 kernel/fork.c:451 finish_task_switch+0x3f1/0x550 kernel/sched/core.c:3256 context_switch kernel/sched/core.c:3388 [inline] __schedule+0x9a8/0xcc0 kernel/sched/core.c:4081 preempt_schedule_irq+0xc1/0x140 kernel/sched/core.c:4338 retint_kernel+0x1b/0x2b RIP: 0010:__sanitizer_cov_trace_pc+0x48/0x50 kernel/kcov.c:112 Code: 80 13 00 00 83 fa 02 75 21 48 8b 91 88 13 00 00 48 8b 32 48 8d 7e 01 8b 89 84 13 00 00 48 39 cf 73 08 48 89 44 f2 08 48 89 3a 0f 1f 80 00 00 00 00 4c 8b 04 24 65 48 8b 04 25 c0 1d 02 00 65 RSP: 0018:ffffc90001e27a08 EFLAGS: 00000293 ORIG_RAX: ffffffffffffff13 RAX: ffffffff8355fb5b RBX: 0000000000000000 RCX: ffff88808c92e3c0 RDX: 0000000000000000 RSI: ffffffff891efc00 RDI: 0000000000000000 RBP: ffffc90001e27a50 R08: 0000000000000001 R09: ffffffff8355fb45 R10: ffff88808c92e3c0 R11: 0000000000000007 R12: ffff88809f320480 R13: ffff88809ad57c90 R14: ffff88809f320499 R15: dffffc0000000000 tomoyo_supervisor+0x274/0x1330 security/tomoyo/common.c:2087 tomoyo_audit_path2_log security/tomoyo/file.c:182 [inline] tomoyo_path2_perm+0x74f/0x9d0 security/tomoyo/file.c:943 tomoyo_path_rename+0xec/0x110 security/tomoyo/tomoyo.c:285 security_path_rename+0x211/0x2d0 security/security.c:1079 do_renameat2+0x94d/0xff0 fs/namei.c:4619 __do_sys_rename fs/namei.c:4669 [inline] __se_sys_rename fs/namei.c:4667 [inline] __x64_sys_rename+0x68/0x80 fs/namei.c:4667 do_syscall_64+0xf7/0x1c0 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7f18d4007527 Code: 32 00 64 83 38 15 74 07 b8 ff ff ff ff 5b c3 48 89 df e8 1c c1 07 00 85 c0 75 ed 31 c0 eb d3 90 90 90 90 b8 52 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d e1 f8 32 00 31 d2 48 29 c2 64 RSP: 002b:00007ffea1026db8 EFLAGS: 00000246 ORIG_RAX: 0000000000000052 RAX: ffffffffffffffda RBX: 000000000187c470 RCX: 00007f18d4007527 RDX: 00007f18d4338e98 RSI: 00007ffea1026df0 RDI: 00007ffea10271f0 RBP: 00000000018693a0 R08: 00007f18d497a7a0 R09: 0000000000000001 R10: 0000000000000001 R11: 0000000000000246 R12: 00000000018743f0 R13: 0000000001863250 R14: 00007ffea1026df0 R15: 0000000000000000