rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-...!: (10500 ticks this GP) idle=6ea/1/0x4000000000000004 softirq=148762/148762 fqs=0 (t=10501 jiffies g=204929 q=353) rcu: rcu_preempt kthread starved for 10502 jiffies! g204929 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1 rcu: RCU grace-period kthread stack dump: rcu_preempt R running task 29264 10 2 0x80004000 Call Trace: context_switch kernel/sched/core.c:3386 [inline] __schedule+0x934/0x1f90 kernel/sched/core.c:4082 schedule+0xdc/0x2b0 kernel/sched/core.c:4156 schedule_timeout+0x486/0xc50 kernel/time/timer.c:1895 rcu_gp_fqs_loop kernel/rcu/tree.c:1658 [inline] rcu_gp_kthread+0xa10/0x1940 kernel/rcu/tree.c:1818 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 NMI backtrace for cpu 1 CPU: 1 PID: 15333 Comm: syz-executor.2 Not tainted 5.5.0-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+0x197/0x210 lib/dump_stack.c:118 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:475 [inline] check_cpu_stall kernel/rcu/tree_stall.h:549 [inline] rcu_pending kernel/rcu/tree.c:3030 [inline] rcu_sched_clock_irq.cold+0x51a/0xc37 kernel/rcu/tree.c:2276 update_process_times+0x2d/0x70 kernel/time/timer.c:1726 tick_sched_handle+0xa2/0x190 kernel/time/tick-sched.c:171 tick_sched_timer+0x53/0x140 kernel/time/tick-sched.c:1314 __run_hrtimer kernel/time/hrtimer.c:1517 [inline] __hrtimer_run_queues+0x364/0xe40 kernel/time/hrtimer.c:1579 hrtimer_interrupt+0x314/0x770 kernel/time/hrtimer.c:1641 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:829 RIP: 0010:skb_dequeue+0x134/0x180 net/core/skbuff.c:3044 Code: 00 00 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 75 3d 4c 89 3b e8 ed 38 56 fb 4c 89 ee 4c 89 f7 e8 02 22 bd 01 4c 89 e0 5b 41 5c <41> 5d 41 5e 41 5f 5d c3 45 31 e4 eb dd e8 3a c2 94 fb e9 41 ff ff RSP: 0018:ffffc90000da8cc0 EFLAGS: 00000206 ORIG_RAX: ffffffffffffff13 RAX: 0000000000000000 RBX: ffff88809feafcd8 RCX: 0000000000000000 RDX: 0000000000000101 RSI: 0000000000000008 RDI: 0000000000000001 RBP: ffffc90000da8cd8 R08: 1ffffffff165d37d R09: fffffbfff165d37e R10: fffffbfff165d37d R11: ffffffff8b2e9bef R12: ffff88809feafca0 R13: 0000000000000286 R14: ffff88809feafcf0 R15: dffffc0000000000 mrp_queue_xmit net/802/mrp.c:350 [inline] mrp_join_timer+0x64/0x80 net/802/mrp.c:595 call_timer_fn+0x1ac/0x780 kernel/time/timer.c:1404 expire_timers kernel/time/timer.c:1449 [inline] __run_timers kernel/time/timer.c:1773 [inline] __run_timers kernel/time/timer.c:1740 [inline] run_timer_softirq+0x6c3/0x1790 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:829 RIP: 0010:__write_once_size include/linux/compiler.h:226 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x48/0x50 kernel/kcov.c:195 Code: 75 2b 8b 90 80 13 00 00 83 fa 02 75 20 48 8b 88 88 13 00 00 8b 80 84 13 00 00 48 8b 11 48 83 c2 01 48 39 d0 76 07 48 89 34 d1 <48> 89 11 5d c3 0f 1f 00 65 4c 8b 04 25 c0 1e 02 00 65 8b 05 88 b0 RSP: 0018:ffffc900045f76c0 EFLAGS: 00000216 ORIG_RAX: ffffffffffffff13 RAX: 0000000000040000 RBX: ffff8880911e5400 RCX: ffffc9000e184000 RDX: 000000000000fd07 RSI: ffffffff8364cf15 RDI: 0000000000000000 RBP: ffffc900045f76c0 R08: ffff8880448d4140 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: dffffc0000000000 R13: 0000000000000000 R14: ffffc900045f77e8 R15: 0000000000000000 tomoyo_check_acl+0x135/0x3e0 security/tomoyo/domain.c:175 tomoyo_path_permission security/tomoyo/file.c:586 [inline] tomoyo_path_permission+0x1fb/0x360 security/tomoyo/file.c:573 tomoyo_check_open_permission+0x3a6/0x3e0 security/tomoyo/file.c:777 tomoyo_file_open security/tomoyo/tomoyo.c:319 [inline] tomoyo_file_open+0xa9/0xd0 security/tomoyo/tomoyo.c:314 security_file_open+0x71/0x300 security/security.c:1529 do_dentry_open+0x37a/0x1380 fs/open.c:784 vfs_open+0xa0/0xd0 fs/open.c:914 do_last fs/namei.c:3359 [inline] path_openat+0x1141/0x2fb0 fs/namei.c:3476 do_filp_open+0x1a1/0x280 fs/namei.c:3506 do_sys_open+0x3fe/0x5d0 fs/open.c:1097 __do_sys_open fs/open.c:1115 [inline] __se_sys_open fs/open.c:1110 [inline] __x64_sys_open+0x7e/0xc0 fs/open.c:1110 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4150e1 Code: 75 14 b8 02 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 04 19 00 00 c3 48 83 ec 08 e8 0a fa ff ff 48 89 04 24 b8 02 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 53 fa ff ff 48 89 d0 48 83 c4 08 48 3d 01 RSP: 002b:00007f4f23744bb0 EFLAGS: 00000293 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 00007f4f237456d4 RCX: 00000000004150e1 RDX: ffffffffffffffeb RSI: 0000000000000000 RDI: 00007f4f23744bd0 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000014 R10: 0000000000000009 R11: 0000000000000293 R12: 00000000ffffffff R13: 0000000000000bdf R14: 00000000004ccc12 R15: 000000000075bf2c