rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-...!: (10499 ticks this GP) idle=506/1/0x4000000000000002 softirq=11270/11270 fqs=36 (t=10500 jiffies g=6377 q=666) rcu: rcu_preempt kthread starved for 10421 jiffies! g6377 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: 8368 Comm: syz-executor.0 Not tainted 5.5.0-rc5-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:1517 [inline] __hrtimer_run_queues+0x403/0x840 kernel/time/hrtimer.c:1579 hrtimer_interrupt+0x38c/0xda0 kernel/time/hrtimer.c:1641 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:mod_memcg_page_state+0x8/0x190 include/linux/memcontrol.h:652 Code: eb 0c e8 eb 27 2e 00 eb 05 e8 e4 27 2e 00 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f 5d c3 0f 1f 44 00 00 55 48 89 e5 41 57 41 56 <41> 54 53 41 89 f6 48 89 fb e8 ba 27 2e 00 48 83 c3 38 48 89 d8 48 RSP: 0018:ffffc900022479a8 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: 1ffff110126e7b51 RBX: ffff88809373da88 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 00000000fffffffc RDI: ffffea00029fbf40 RBP: ffffc900022479b8 R08: 000000000003a728 R09: ffffed1012769319 R10: ffffed1012769319 R11: 0000000000000000 R12: ffff88809373db20 R13: dffffc0000000000 R14: 1ffff110126e7b64 R15: ffff888093b498b8 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:check_kcov_mode kernel/kcov.c:164 [inline] RIP: 0010:write_comp_data kernel/kcov.c:208 [inline] RIP: 0010:__sanitizer_cov_trace_cmp8+0x21/0x80 kernel/kcov.c:254 Code: 2e 0f 1f 84 00 00 00 00 00 4c 8b 04 24 65 48 8b 14 25 c0 1d 02 00 65 8b 05 38 5d 8b 7e a9 00 01 1f 00 75 61 8b 82 80 13 00 00 <83> f8 03 75 56 48 8b 8a 88 13 00 00 44 8b 8a 84 13 00 00 49 c1 e1 RSP: 0018:ffffc90002247c18 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: 0000000000000000 RBX: 0000000000008933 RCX: 0000000000000000 RDX: ffff88808e16e040 RSI: 0000000000006364 RDI: 0000000000008933 RBP: ffffc90002247c48 R08: ffffffff8360d9fa R09: ffffffff8362087c R10: ffff88808e16e040 R11: 0000000000000002 R12: 0000000000006364 R13: dffffc0000000000 R14: ffff88809ecf5f80 R15: ffffc90002247cf0 tomoyo_check_acl+0x133/0x3a0 security/tomoyo/domain.c:175 tomoyo_path_number_perm+0x354/0x640 security/tomoyo/file.c:733 tomoyo_file_ioctl+0x23/0x30 security/tomoyo/tomoyo.c:335 security_file_ioctl+0x6d/0xd0 security/security.c:1409 ksys_ioctl fs/ioctl.c:747 [inline] __do_sys_ioctl fs/ioctl.c:756 [inline] __se_sys_ioctl fs/ioctl.c:754 [inline] __x64_sys_ioctl+0xa3/0x120 fs/ioctl.c:754 do_syscall_64+0xf7/0x1c0 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45adb7 Code: 48 83 c4 08 48 89 d8 5b 5d c3 66 0f 1f 84 00 00 00 00 00 48 89 e8 48 f7 d8 48 39 c3 0f 92 c0 eb 92 66 90 b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 0d b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f7e33df1c88 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000045adb7 RDX: 0000000000000000 RSI: 0000000000006364 RDI: 00000000000000e8 RBP: 000000000075bfa8 R08: 00007f7e33df2700 R09: 00007f7e33df2700 R10: 00007f7e33df29d0 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffdd3b4159f R14: 00007f7e33df29c0 R15: 000000000075bf2c