rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: (detected by 1, t=10502 jiffies, g=5993, q=224) rcu: All QSes seen, last rcu_preempt kthread activity 10503 (4294953723-4294943220), jiffies_till_next_fqs=1, root ->qsmask 0x0 syz-executor.2 R running task 24480 8135 8134 0x0000400a 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: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:__memcg_kmem_uncharge+0xd/0x2e0 mm/memcontrol.c:2909 Code: 81 c3 08 02 00 00 48 89 df 4c 89 f6 e8 dc 7d ff ff 5b 41 5e 5d c3 0f 1f 80 00 00 00 00 55 48 89 e5 41 57 41 56 41 55 41 54 53 <50> 89 f3 49 89 fc 48 b8 00 00 00 00 00 fc ff df 4c 8d 77 38 4d 89 RSP: 0018:ffffc900025679f8 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: ffffffff81486ea4 RBX: ffffea000238c4c0 RCX: ffff888090c0c640 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffea000238c4c0 RBP: ffffc90002567a20 R08: dffffc0000000000 R09: fffffbfff120248a R10: fffffbfff120248a R11: 0000000000000000 R12: ffff88808b233920 R13: dffffc0000000000 R14: 1ffff11011646724 R15: ffff8880a147f9e8 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 schedule+0x181/0x210 kernel/sched/core.c:4155 pipe_wait+0x127/0x1e0 fs/pipe.c:119 pipe_read+0x665/0x9e0 fs/pipe.c:368 call_read_iter include/linux/fs.h:1896 [inline] new_sync_read fs/read_write.c:414 [inline] __vfs_read+0x59e/0x730 fs/read_write.c:427 vfs_read+0x1dd/0x420 fs/read_write.c:461 ksys_read+0x117/0x220 fs/read_write.c:587 __do_sys_read fs/read_write.c:597 [inline] __se_sys_read fs/read_write.c:595 [inline] __x64_sys_read+0x7b/0x90 fs/read_write.c:595 do_syscall_64+0xf7/0x1c0 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x414190 Code: 01 f0 ff ff 0f 83 90 1b 00 00 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 83 3d dd 42 66 00 00 75 14 b8 00 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 64 1b 00 00 c3 48 83 ec 08 e8 6a fc ff ff RSP: 002b:00007fffef9ee208 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000414190 RDX: 0000000000000038 RSI: 0000000000758040 RDI: 00000000000000f9 RBP: 0000000000715460 R08: 0000000000006000 R09: 0000000000004000 R10: 00007fffef9edba0 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fffef9ee240 R14: 0000000000000003 R15: 00007fffef9ee250 rcu: rcu_preempt kthread starved for 10534 jiffies! g5993 f0x2 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