rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-...!: (10499 ticks this GP) idle=ce2/1/0x4000000000000002 softirq=11656/11656 fqs=8 (t=10501 jiffies g=6785 q=366) rcu: rcu_preempt kthread starved for 10486 jiffies! g6785 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1 rcu: RCU grace-period kthread stack dump: rcu_preempt R running task 28984 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: 8387 Comm: syz-executor.4 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+0x168/0x190 include/linux/memcontrol.h:655 Code: c7 68 95 2a 89 e8 d8 8e 6a 00 48 83 3d 68 fd e1 07 00 74 2d e8 79 26 2e 00 4c 89 ff 57 9d 0f 1f 44 00 00 5b 41 5c 41 5e 41 5f <5d> c3 e8 61 26 2e 00 0f 0b e8 5a 26 2e 00 0f 0b e8 53 26 2e 00 0f RSP: 0018:ffffc90001f47720 EFLAGS: 00000293 ORIG_RAX: ffffffffffffff13 RAX: ffffffff814897d3 RBX: ffff888097105808 RCX: ffff888099b78380 RDX: 0000000000000000 RSI: 00000000fffffffc RDI: ffffea00025baac0 RBP: ffffc90001f47720 R08: 000000000003a728 R09: ffffed10147776b1 R10: ffffed10147776b1 R11: 0000000000000000 R12: ffff8880971058a0 R13: dffffc0000000000 R14: 1ffff11012e20b14 R15: ffff8880a3bbb578 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 schedule+0x181/0x210 kernel/sched/core.c:4155 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4214 __mutex_lock_common+0x1411/0x2e10 kernel/locking/mutex.c:1033 __mutex_lock kernel/locking/mutex.c:1103 [inline] mutex_lock_interruptible_nested+0x1b/0x30 kernel/locking/mutex.c:1140 tomoyo_get_name+0x47/0x540 security/tomoyo/memory.c:164 tomoyo_parse_name_union+0x169/0x1f0 security/tomoyo/util.c:258 tomoyo_update_path_number_acl security/tomoyo/file.c:687 [inline] tomoyo_write_file+0x756/0x1040 security/tomoyo/file.c:1034 tomoyo_write_domain2 security/tomoyo/common.c:1152 [inline] tomoyo_add_entry security/tomoyo/common.c:2042 [inline] tomoyo_supervisor+0x1021/0x1330 security/tomoyo/common.c:2103 tomoyo_audit_path_number_log security/tomoyo/file.c:235 [inline] tomoyo_path_number_perm+0x471/0x640 security/tomoyo/file.c:734 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:00007ffe39f1b3e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 000000000045adb7 RDX: 00007ffe39f1b3f0 RSI: 0000000000008933 RDI: 0000000000000004 RBP: 00000000004c04a0 R08: 000000000000000a R09: 0000000000000008 R10: 0000000000000078 R11: 0000000000000246 R12: 0000000000000003 R13: 0000000000000000 R14: 0000000000000006 R15: 00007ffe39f1b6b0