INFO: task syz-executor.5:29623 blocked for more than 140 seconds. Not tainted 4.14.226-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D28912 29623 10728 0x00000004 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3384 schedule+0x8d/0x1b0 kernel/sched/core.c:3428 schedule_timeout+0x80a/0xe90 kernel/time/timer.c:1724 do_wait_for_common kernel/sched/completion.c:91 [inline] __wait_for_common kernel/sched/completion.c:112 [inline] wait_for_common+0x272/0x430 kernel/sched/completion.c:123 kthread_stop+0xce/0x640 kernel/kthread.c:555 kvm_mmu_pre_destroy_vm+0x41/0x50 arch/x86/kvm/mmu.c:5903 kvm_destroy_vm arch/x86/kvm/../../../virt/kvm/kvm_main.c:769 [inline] kvm_put_kvm+0x30a/0xa90 arch/x86/kvm/../../../virt/kvm/kvm_main.c:806 kvm_vm_release+0x3f/0x50 arch/x86/kvm/../../../virt/kvm/kvm_main.c:817 __fput+0x25f/0x7a0 fs/file_table.c:210 task_work_run+0x11f/0x190 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:191 [inline] exit_to_usermode_loop+0x1ad/0x200 arch/x86/entry/common.c:164 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline] syscall_return_slowpath arch/x86/entry/common.c:270 [inline] do_syscall_64+0x4a3/0x640 arch/x86/entry/common.c:297 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x41926b RSP: 002b:00007ffd90c60540 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000005 RCX: 000000000041926b RDX: 00000000005702c0 RSI: 00000000089075c3 RDI: 0000000000000004 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000001b32322400 R10: 00007ffd90c60630 R11: 0000000000000293 R12: 00000000000537bb R13: 00000000000003e8 R14: 000000000056bf60 R15: 0000000000053789 Showing all locks held in the system: 1 lock held by khungtaskd/1528: #0: (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4548 2 locks held by agetty/7915: #0: (&tty->ldisc_sem){++++}, at: [] tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:284 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e3/0x1680 drivers/tty/n_tty.c:2156 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1528 Comm: khungtaskd Not tainted 4.14.226-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x1b2/0x281 lib/dump_stack.c:58 nmi_cpu_backtrace.cold+0x57/0x93 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x13a/0x180 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:140 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:195 [inline] watchdog+0x5b9/0xb40 kernel/hung_task.c:274 kthread+0x30d/0x420 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 4618 Comm: systemd-journal Not tainted 4.14.226-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff8880a163a6c0 task.stack: ffff8880a1640000 RIP: 0010:rcu_is_watching+0x0/0xb0 kernel/rcu/tree.c:1126 RSP: 0018:ffff8880a1647af8 EFLAGS: 00000046 RAX: 0000000000000007 RBX: ffffffff893d0220 RCX: 0000000000000001 RDX: 0000000000000000 RSI: 0000000000000002 RDI: ffff8880a163af44 RBP: ffff8880a163a6c0 R08: 0000000000001000 R09: ffffed10166ba800 R10: 0000000000000000 R11: ffff8880a163a6c0 R12: 0000000000000001 R13: ffff88813fffe5d0 R14: 00000000000442c0 R15: 0000000000000000 FS: 00007fe351f688c0(0000) GS:ffff8880ba500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fe34db8e018 CR3: 00000000a16c0000 CR4: 00000000001426e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_read_lock_sched_held+0xc6/0x1d0 kernel/rcu/update.c:111 trace_mm_page_alloc include/trace/events/kmem.h:195 [inline] __alloc_pages_nodemask+0x1a6e/0x2720 mm/page_alloc.c:4214 __alloc_pages include/linux/gfp.h:484 [inline] __alloc_pages_node include/linux/gfp.h:497 [inline] kmem_getpages mm/slab.c:1419 [inline] cache_grow_begin+0x91/0x630 mm/slab.c:2676 cache_alloc_refill+0x273/0x350 mm/slab.c:3043 ____cache_alloc mm/slab.c:3125 [inline] __do_cache_alloc mm/slab.c:3347 [inline] slab_alloc mm/slab.c:3382 [inline] kmem_cache_alloc+0x333/0x3c0 mm/slab.c:3550 getname_flags+0xc8/0x550 fs/namei.c:138 do_sys_open+0x1ce/0x410 fs/open.c:1075 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7fe3514f7840 RSP: 002b:00007ffef5610f98 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 00007ffef56112a0 RCX: 00007fe3514f7840 RDX: 00000000000001a0 RSI: 0000000000080042 RDI: 0000564d81556340 RBP: 000000000000000d R08: 000000000000c0c1 R09: 00000000ffffffff R10: 0000000000000069 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000564d81552040 R14: 00007ffef5611260 R15: 0000564d8155f530 Code: e8 06 dc 37 00 e9 36 ff ff ff e8 fc db 37 00 e9 7a ff ff ff e8 f2 db 37 00 e9 51 ff ff ff 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 <53> 48 83 ec 08 65 ff 05 24 11 bb 7e e8 0f 89 d1 01 48 c7 c3 40