rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: (detected by 1, t=10502 jiffies, g=6565, q=100) rcu: All QSes seen, last rcu_preempt kthread activity 10503 (4294954013-4294943510), jiffies_till_next_fqs=1, root ->qsmask 0x0 syz-executor.0 R running task 27912 8422 8403 0x80004008 Call Trace: sched_show_task+0x40f/0x560 kernel/sched/core.c:5954 print_other_cpu_stall kernel/rcu/tree_stall.h:410 [inline] check_cpu_stall kernel/rcu/tree_stall.h:538 [inline] rcu_pending kernel/rcu/tree.c:2827 [inline] rcu_sched_clock_irq+0x1861/0x1ad0 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:__memcg_kmem_uncharge+0x132/0x1a0 mm/memcontrol.c:2924 Code: 89 d8 48 c1 e8 03 42 8a 04 28 84 c0 75 3b f6 03 01 75 10 49 83 c7 10 4c 89 ff 48 8b 75 d0 e8 f5 90 00 00 48 83 c4 08 5b 41 5c <41> 5d 41 5e 41 5f 5d c3 44 89 e1 80 e1 07 80 c1 03 38 c1 7c 96 4c RSP: 0018:ffffc900027e7a38 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13 RAX: 0000000000000001 RBX: ffffea000254c6c0 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffea000254c6c0 RBP: ffffc900027e7a50 R08: dffffc0000000000 R09: fffffbfff12c962d R10: fffffbfff12c962d R11: 0000000000000000 R12: ffff88809441a320 R13: 1ffffd40004a98df R14: ffffea000254c6f8 R15: 0000000000000000 memcg_kmem_uncharge include/linux/memcontrol.h:1402 [inline] free_thread_stack+0x12e/0x590 kernel/fork.c:284 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_common kernel/sched/core.c:4236 [inline] preempt_schedule+0xdb/0x120 kernel/sched/core.c:4261 ___preempt_schedule+0x16/0x18 arch/x86/entry/thunk_64.S:50 __raw_spin_unlock include/linux/spinlock_api_smp.h:152 [inline] _raw_spin_unlock+0x3a/0x40 kernel/locking/spinlock.c:183 spin_unlock include/linux/spinlock.h:378 [inline] task_unlock include/linux/sched/task.h:176 [inline] mm_update_next_owner+0x5e9/0x680 kernel/exit.c:426 exit_mm+0x502/0x590 kernel/exit.c:484 do_exit+0x572/0x2000 kernel/exit.c:788 do_group_exit+0x15c/0x2b0 kernel/exit.c:899 __do_sys_exit_group+0x17/0x20 kernel/exit.c:910 __se_sys_exit_group+0x14/0x20 kernel/exit.c:908 __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:908 do_syscall_64+0xf7/0x1c0 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45af49 Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffd0a1e8ed8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 000000000000001e RCX: 000000000045af49 RDX: 0000000000414ae1 RSI: fffffffffffffff7 RDI: 0000000000000000 RBP: 0000000000000000 R08: ffffffffffffffff R09: 00007ffd0a1e8f30 R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffd0a1e8f30 R14: 0000000000000000 R15: 00007ffd0a1e8f40 rcu: rcu_preempt kthread starved for 10536 jiffies! g6565 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0 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