rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P8611 (detected by 1, t=10503 jiffies, g=6853, q=738) syz-executor.1 R running task 27984 8611 8596 0x0000400a Call Trace: sched_show_task+0x40f/0x560 kernel/sched/core.c:5954 rcu_print_detail_task_stall_rnp kernel/rcu/tree_stall.h:190 [inline] print_other_cpu_stall kernel/rcu/tree_stall.h:398 [inline] check_cpu_stall kernel/rcu/tree_stall.h:538 [inline] rcu_pending kernel/rcu/tree.c:2827 [inline] rcu_sched_clock_irq+0x16b1/0x1ad0 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+0x1d/0x1a0 mm/memcontrol.c:2909 Code: 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 f5 49 c1 ed 03 41 80 7c 05 00 00 74 08 4c 89 f7 RSP: 0018:ffffc900023b7948 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffff8880a4324480 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffea00025d38c0 RBP: ffffc900023b7978 R08: 000000000003a728 R09: ffffed10121f2ad1 R10: ffffed10121f2ad1 R11: 0000000000000000 R12: ffffea00025d38c0 R13: dffffc0000000000 R14: 1ffff1101283c454 R15: ffff888090f95678 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_notrace+0xdb/0x120 kernel/sched/core.c:4309 ___preempt_schedule_notrace+0x16/0x27 arch/x86/entry/thunk_64.S:51 rcu_is_watching+0x82/0xa0 kernel/rcu/tree.c:923 rcu_read_unlock include/linux/rcupdate.h:667 [inline] memcg_kmem_get_cache+0x2e8/0x570 mm/memcontrol.c:2807 slab_pre_alloc_hook mm/slab.h:572 [inline] slab_alloc mm/slab.c:3306 [inline] kmem_cache_alloc+0x86/0x2e0 mm/slab.c:3484 kmem_cache_zalloc include/linux/slab.h:660 [inline] __delayacct_tsk_init+0x20/0x90 kernel/delayacct.c:36 delayacct_tsk_init include/linux/delayacct.h:102 [inline] copy_process+0x922/0x5510 kernel/fork.c:1957 _do_fork+0x13e/0x660 kernel/fork.c:2421 __do_sys_clone kernel/fork.c:2576 [inline] __se_sys_clone kernel/fork.c:2557 [inline] __x64_sys_clone+0x20b/0x250 kernel/fork.c:2557 do_syscall_64+0xf7/0x1c0 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45d919 Code: ff 48 85 f6 0f 84 d7 8c fb ff 48 83 ee 10 48 89 4e 08 48 89 3e 48 89 d7 4c 89 c2 4d 89 c8 4c 8b 54 24 08 b8 38 00 00 00 0f 05 <48> 85 c0 0f 8c ae 8c fb ff 74 01 c3 31 ed 48 f7 c7 00 00 01 00 75 RSP: 002b:00007fffefeaa588 EFLAGS: 00000202 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 00007fa5aa7d6700 RCX: 000000000045d919 RDX: 00007fa5aa7d69d0 RSI: 00007fa5aa7d5db0 RDI: 00000000003d0f00 RBP: 00007fffefeaa7a0 R08: 00007fa5aa7d6700 R09: 00007fa5aa7d6700 R10: 00007fa5aa7d69d0 R11: 0000000000000202 R12: 0000000000000000 R13: 00007fffefeaa63f R14: 00007fa5aa7d69c0 R15: 000000000075bf2c rcu: rcu_preempt kthread starved for 10501 jiffies! g6853 f0x0 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