rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-...!: (10499 ticks this GP) idle=142/1/0x4000000000000002 softirq=10267/10267 fqs=3 (t=10500 jiffies g=6485 q=67) rcu: rcu_preempt kthread starved for 10494 jiffies! g6485 f0x0 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 NMI backtrace for cpu 0 CPU: 0 PID: 8135 Comm: blkid Not tainted 5.4.0-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: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+0x0/0x2e0 mm/memcontrol.c:2909 Code: 00 eb 1b 83 3d 80 ce 8c 07 00 74 12 48 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 RSP: 0018:ffffc90001fc7670 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: ffffffff81486ea4 RBX: ffffea000238b6c0 RCX: ffff888098e78280 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffea000238b6c0 RBP: ffffc90001fc76b0 R08: 000000000003a768 R09: ffffed10150e074f R10: ffffed10150e074f R11: 0000000000000000 R12: ffff8880a6c8cc20 R13: dffffc0000000000 R14: 1ffff11014d91984 R15: ffff8880a8703a68 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_irq+0xc1/0x140 kernel/sched/core.c:4338 retint_kernel+0x1b/0x2b RIP: 0010:memset_erms+0xb/0x10 arch/x86/lib/memset_64.S:67 Code: 03 40 0f b6 f6 48 b8 01 01 01 01 01 01 01 01 48 0f af c6 f3 48 ab 89 d1 f3 aa 4c 89 c8 c3 90 49 89 f9 40 88 f0 48 89 d1 f3 aa <4c> 89 c8 c3 90 49 89 fa 40 0f b6 ce 48 b8 01 01 01 01 01 01 01 01 RSP: 0018:ffffc90001fc78c0 EFLAGS: 00000256 ORIG_RAX: ffffffffffffff02 RAX: 1ffff110131cf100 RBX: ffffc90001fc79e0 RCX: 0000000000000000 RDX: 0000000000000010 RSI: 0000000000000000 RDI: ffffc90001fc79f0 RBP: ffffc90001fc78e0 R08: dffffc0000000000 R09: ffffc90001fc79e0 R10: fffff520003f8f3e R11: 0000000000000000 R12: 1ffff11015056add R13: dffffc0000000000 R14: 0000000000000000 R15: 0000000000000010 init_rss_vec mm/memory.c:478 [inline] zap_pte_range+0x1a7f/0x1c30 mm/memory.c:1037 zap_pmd_range mm/memory.c:1184 [inline] zap_pud_range mm/memory.c:1213 [inline] zap_p4d_range mm/memory.c:1234 [inline] unmap_page_range+0x9b5/0xb00 mm/memory.c:1255 unmap_single_vma+0x1d4/0x2e0 mm/memory.c:1300 unmap_vmas+0x163/0x2a0 mm/memory.c:1332 exit_mmap+0x27b/0x530 mm/mmap.c:3140 __mmput+0x120/0x3a0 kernel/fork.c:1082 mmput+0x5d/0x70 kernel/fork.c:1103 exit_mm+0x50a/0x590 kernel/exit.c:485 do_exit+0x544/0x2020 kernel/exit.c:784 do_group_exit+0x15c/0x2b0 kernel/exit.c:895 __do_sys_exit_group+0x17/0x20 kernel/exit.c:906 __se_sys_exit_group+0x14/0x20 kernel/exit.c:904 __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:904 do_syscall_64+0xf7/0x1c0 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7f67686b81e8 Code: Bad RIP value. RSP: 002b:00007ffc441137e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f67686b81e8 RDX: 0000000000000002 RSI: 000000000000003c RDI: 0000000000000002 RBP: 00007f676898d840 R08: 00000000000000e7 R09: ffffffffffffffa8 R10: 00007f6768993740 R11: 0000000000000246 R12: 00007f676898d840 R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000000