INFO: task syz-executor.5:18478 blocked for more than 140 seconds. Not tainted 4.14.305-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D28912 18478 8007 0x00000004 Call Trace: context_switch kernel/sched/core.c:2811 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3386 schedule+0x8d/0x1b0 kernel/sched/core.c:3430 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:5912 kvm_destroy_vm arch/x86/kvm/../../../virt/kvm/kvm_main.c:781 [inline] kvm_put_kvm+0x30a/0xab0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:819 kvm_vm_release+0x3f/0x50 arch/x86/kvm/../../../virt/kvm/kvm_main.c:830 __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+0x5e/0xd3 RIP: 0033:0x7f920501efab caif:caif_disconnect_client(): nothing to disconnect RSP: 002b:00007ffc59424030 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000005 RCX: 00007f920501efab RDX: 00007f9204be1498 RSI: ffffffffffffffff RDI: 0000000000000004 RBP: 00007f920518e980 R08: 0000000000000000 R09: 00007f9204be1000 R10: 00007f9204be14a0 R11: 0000000000000293 R12: 00000000001a34f7 R13: 00007ffc59424130 R14: 00007f920518cf80 R15: 0000000000000032 Showing all locks held in the system: 1 lock held by khungtaskd/1532: #0: (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4548 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1532 Comm: khungtaskd Not tainted 4.14.305-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/21/2023 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:406 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 28660 Comm: systemd-udevd Not tainted 4.14.305-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/21/2023 task: ffff8880afc92280 task.stack: ffff8880a1ff8000 RIP: 0010:find_stack lib/stackdepot.c:178 [inline] RIP: 0010:depot_save_stack+0xf8/0x3f0 lib/stackdepot.c:229 RSP: 0018:ffff8880a1fff8b0 EFLAGS: 00000246 RAX: 00000000000af838 RBX: 00000000c51af838 RCX: 0000000000000001 RDX: 0000000000000008 RSI: 00000000a664e88b RDI: 0000000004a53448 RBP: ffff8880a1fff908 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: ffff8880afc92280 R12: 0000000000000040 R13: 0000000000000008 R14: ffff8880a1fff920 R15: ffff8880a3817490 FS: 00007ff5632a38c0(0000) GS:ffff8880ba400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f9d71f420c0 CR3: 00000000b3118000 CR4: 00000000003426f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: save_stack mm/kasan/kasan.c:453 [inline] set_track mm/kasan/kasan.c:459 [inline] kasan_kmalloc+0x139/0x160 mm/kasan/kasan.c:551 slab_post_alloc_hook mm/slab.h:442 [inline] slab_alloc mm/slab.c:3390 [inline] kmem_cache_alloc+0x111/0x3c0 mm/slab.c:3550 kmem_cache_zalloc include/linux/slab.h:651 [inline] get_empty_filp+0x86/0x3f0 fs/file_table.c:123 path_openat+0x84/0x2970 fs/namei.c:3547 do_filp_open+0x179/0x3c0 fs/namei.c:3605 do_sys_open+0x296/0x410 fs/open.c:1081 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x5e/0xd3 RIP: 0033:0x7ff5623e9840 RSP: 002b:00007fffa99b5098 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 0000000000000124 RCX: 00007ff5623e9840 RDX: 0000000000000124 RSI: 0000000000080141 RDI: 00007fffa99b50c0 RBP: 00007fffa99b50c0 R08: 000000000000c0c0 R09: 0000562e390301c8 R10: 00007fffa99b50c0 R11: 0000000000000246 R12: 0000000000000018 R13: 00007fffa99b50c0 R14: 0000562e3903fbd0 R15: 000000000000000e Code: 8b 3c c5 40 94 0b 8c 48 89 04 24 4d 85 ff 74 5b 49 63 d5 4c 8d 24 d5 00 00 00 00 eb 08 4d 8b 3f 4d 85 ff 74 46 41 3b 5f 08 75 f2 <45> 3b 6f 0c 75 ec 49 8d 77 18 4c 89 e2 4c 89 f7 e8 23 35 d5 03