rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: (detected by 0, t=10502 jiffies, g=6485, q=140) rcu: All QSes seen, last rcu_preempt kthread activity 10503 (4294953604-4294943101), jiffies_till_next_fqs=1, root ->qsmask 0x0 syz-executor.1 R running task 29000 8208 8188 0x0000400e 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+0x217/0x2e0 mm/memcontrol.c:2925 Code: c7 98 4b 0d 89 e8 59 97 00 00 bf 01 00 00 00 e8 2f e3 9b ff 65 8b 05 d4 fd 4a 7e 85 c0 74 53 48 83 c4 08 5b 41 5c 41 5d 41 5e <41> 5f 5d c3 49 8d 5f 10 48 89 df be 08 00 00 00 e8 04 c1 fa ff 48 RSP: 0018:ffffc90002047830 EFLAGS: 00000292 ORIG_RAX: ffffffffffffff13 RAX: 0000000000000001 RBX: ffffea0002a1f600 RCX: 0000000000000000 RDX: ffffc9000705b000 RSI: 0000000000000000 RDI: ffffea0002a1f600 RBP: ffffc90002047838 R08: dffffc0000000000 R09: fffffbfff12877ed R10: fffffbfff12877ed R11: 0000000000000000 R12: ffff8880a62edc20 R13: dffffc0000000000 R14: 1ffff11014c5db84 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 schedule+0x181/0x210 kernel/sched/core.c:4155 freezable_schedule include/linux/freezer.h:172 [inline] futex_wait_queue_me+0x2a3/0x4b0 kernel/futex.c:2704 futex_wait+0x252/0x770 kernel/futex.c:2810 do_futex+0x437/0x3d60 kernel/futex.c:3881 __do_sys_futex kernel/futex.c:3942 [inline] __se_sys_futex+0x28c/0x360 kernel/futex.c:3910 __x64_sys_futex+0xe5/0x100 kernel/futex.c:3910 do_syscall_64+0xf7/0x1c0 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45a679 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:00007f7748e2bcf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: ffffffffffffffda RBX: 000000000075bf28 RCX: 000000000045a679 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000075bf28 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000075bf2c R13: 00007ffc0de541ff R14: 00007f7748e2c9c0 R15: 000000000075bf2c rcu: rcu_preempt kthread starved for 10537 jiffies! g6485 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