rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-...!: (10499 ticks this GP) idle=842/1/0x4000000000000002 softirq=10556/10556 fqs=1 (t=10500 jiffies g=5957 q=88) rcu: rcu_preempt kthread starved for 10498 jiffies! g5957 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0 rcu: RCU grace-period kthread stack dump: rcu_preempt R running task 28864 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 1 CPU: 1 PID: 8106 Comm: udevd 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:mod_memcg_page_state+0x30/0x190 include/linux/memcontrol.h:653 Code: 41 56 41 54 53 41 89 f6 48 89 fb e8 da 28 2e 00 48 83 c3 38 48 89 d8 48 c1 e8 03 49 bc 00 00 00 00 00 fc ff df 42 80 3c 20 00 <74> 08 48 89 df e8 b6 9f 69 00 48 8b 1b 48 85 db 0f 84 d8 00 00 00 RSP: 0018:ffffc90002377628 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: 1ffffd40004c1637 RBX: ffffea000260b1b8 RCX: ffff8880a820a600 RDX: 0000000000000000 RSI: 00000000fffffffc RDI: ffffea000260b180 RBP: ffffc90002377648 R08: 000000000003a768 R09: ffffed101204c2e7 R10: ffffed101204c2e7 R11: 0000000000000000 R12: dffffc0000000000 R13: dffffc0000000000 R14: 00000000fffffffc R15: ffff888090261728 free_thread_stack+0x168/0x590 kernel/fork.c:280 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:arch_local_irq_restore arch/x86/include/asm/paravirt.h:752 [inline] RIP: 0010:lock_acquire+0x1b2/0x250 kernel/locking/lockdep.c:4488 Code: c1 e8 03 42 80 3c 30 00 74 0c 48 c7 c7 28 96 0a 89 e8 b2 7e 56 00 48 83 3d d2 01 af 07 00 0f 84 9c 00 00 00 48 8b 7d c0 57 9d <0f> 1f 44 00 00 48 83 c4 30 5b 41 5c 41 5d 41 5e 41 5f 5d c3 44 89 RSP: 0018:ffffc900023778a0 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13 RAX: 1ffffffff12152c5 RBX: 0000000000000000 RCX: ffffffff815c6b62 RDX: dffffc0000000000 RSI: 0000000000000008 RDI: 0000000000000286 RBP: ffffc900023778f8 R08: dffffc0000000000 R09: fffffbfff13c8d2d R10: fffffbfff13c8d2d R11: 0000000000000000 R12: 0000000000000001 R13: 0000000000000000 R14: dffffc0000000000 R15: ffff888098e2c4e8 down_write+0x57/0x140 kernel/locking/rwsem.c:1534 i_mmap_lock_write include/linux/fs.h:526 [inline] unlink_file_vma+0x7d/0x1b0 mm/mmap.c:168 free_pgtables+0x1b6/0x300 mm/memory.c:414 exit_mmap+0x28a/0x530 mm/mmap.c:3141 __mmput+0x120/0x3a0 kernel/fork.c:1082 mmput+0x5d/0x70 kernel/fork.c:1103 exec_mmap fs/exec.c:1047 [inline] flush_old_exec+0x551/0x6d0 fs/exec.c:1280 load_elf_binary+0x652/0x3670 fs/binfmt_elf.c:847 search_binary_handler+0x1a5/0x660 fs/exec.c:1658 exec_binprm fs/exec.c:1701 [inline] __do_execve_file+0x1573/0x1cd0 fs/exec.c:1821 do_execveat_common fs/exec.c:1867 [inline] do_execve fs/exec.c:1884 [inline] __do_sys_execve fs/exec.c:1960 [inline] __se_sys_execve fs/exec.c:1955 [inline] __x64_sys_execve+0x94/0xb0 fs/exec.c:1955 do_syscall_64+0xf7/0x1c0 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7f3411422207 Code: Bad RIP value. RSP: 002b:00007ffdd42c76f8 EFLAGS: 00000202 ORIG_RAX: 000000000000003b RAX: ffffffffffffffda RBX: 00000000ffffffff RCX: 00007f3411422207 RDX: 00000000008bc420 RSI: 00007ffdd42c77f0 RDI: 00007ffdd42c8800 RBP: 0000000000625500 R08: 0000000000001f76 R09: 0000000000001f76 R10: 0000000000000000 R11: 0000000000000202 R12: 00000000008bc420 R13: 0000000000000007 R14: 00000000008b7250 R15: 0000000000000005