kvm: vcpu 0: requested 8 ns lapic timer period limited to 500000 ns kvm: vcpu 0: requested 8 ns lapic timer period limited to 500000 ns kvm: vcpu 0: requested 8 ns lapic timer period limited to 500000 ns kvm: vcpu 0: requested 8 ns lapic timer period limited to 500000 ns INFO: task syz-executor.3:12252 blocked for more than 140 seconds. Not tainted 4.14.295-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.3 D28288 12252 8024 0x00000004 Call Trace: context_switch kernel/sched/core.c:2811 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3387 schedule+0x8d/0x1b0 kernel/sched/core.c:3431 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 flush_work+0x3fe/0x770 kernel/workqueue.c:2894 __cancel_work_timer+0x321/0x460 kernel/workqueue.c:2965 p9_conn_destroy net/9p/trans_fd.c:898 [inline] p9_fd_close+0x28d/0x420 net/9p/trans_fd.c:925 p9_client_create+0x736/0x12c0 net/9p/client.c:1093 v9fs_session_init+0x1c5/0x1540 fs/9p/v9fs.c:422 v9fs_mount+0x73/0x860 fs/9p/vfs_super.c:135 mount_fs+0x92/0x2a0 fs/super.c:1237 vfs_kern_mount.part.0+0x5b/0x470 fs/namespace.c:1046 vfs_kern_mount fs/namespace.c:1036 [inline] do_new_mount fs/namespace.c:2572 [inline] do_mount+0xe65/0x2a30 fs/namespace.c:2905 SYSC_mount fs/namespace.c:3121 [inline] SyS_mount+0xa8/0x120 fs/namespace.c:3098 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7f78e8ee35a9 RSP: 002b:00007f78e7814168 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f78e9004120 RCX: 00007f78e8ee35a9 RDX: 0000000020000080 RSI: 0000000020000300 RDI: 0000000000000000 RBP: 00007f78e8f3e580 R08: 0000000020000740 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffc5f64347f R14: 00007f78e7814300 R15: 0000000000022000 Showing all locks held in the system: 1 lock held by khungtaskd/1534: #0: (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4548 2 locks held by kworker/0:2/4626: #0: ("events"){+.+.}, at: [] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2088 #1: ((&m->rq)){+.+.}, at: [] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2092 1 lock held by in:imklog/7710: #0: (&f->f_pos_lock){+.+.}, at: [] __fdget_pos+0x1fb/0x2b0 fs/file.c:819 2 locks held by kworker/1:3/8332: #0: ("events"){+.+.}, at: [] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2088 #1: ((&m->rq)){+.+.}, at: [] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2092 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1534 Comm: khungtaskd Not tainted 4.14.295-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022 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: 16201 Comm: syz-executor.4 Not tainted 4.14.295-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022 task: ffff8880624524c0 task.stack: ffff8880626f8000 RIP: 0010:vmcs_load+0x5e/0x90 arch/x86/kvm/vmx.c:1727 RSP: 0018:ffff8880626ff768 EFLAGS: 00000202 RAX: ffff8880626ff788 RBX: 1ffff1100c4dfeed RCX: ffffc90007810000 RDX: 0000000000040000 RSI: ffffffff81250eb3 RDI: ffff8880a9354000 RBP: ffff8880a9354000 R08: ffff88806180e220 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff88806180e278 R13: 0000000000000001 R14: 0000000000000001 R15: 0000000000000001 FS: 00007f95f20c5700(0000) GS:ffff8880ba500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 00000000b44b9000 CR4: 00000000003426e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: vmx_vcpu_load+0x1de/0xd10 arch/x86/kvm/vmx.c:2552 kvm_arch_vcpu_load+0x11a/0x750 arch/x86/kvm/x86.c:3041 __fire_sched_in_preempt_notifiers kernel/sched/core.c:2545 [inline] fire_sched_in_preempt_notifiers kernel/sched/core.c:2551 [inline] finish_task_switch+0x218/0x610 kernel/sched/core.c:2681 context_switch kernel/sched/core.c:2814 [inline] __schedule+0x893/0x1de0 kernel/sched/core.c:3387 preempt_schedule_common+0x45/0xc0 kernel/sched/core.c:3511 ___preempt_schedule+0x16/0x18 vcpu_enter_guest arch/x86/kvm/x86.c:7298 [inline] vcpu_run arch/x86/kvm/x86.c:7380 [inline] kvm_arch_vcpu_ioctl_run+0x49a5/0x5c80 arch/x86/kvm/x86.c:7547 kvm_vcpu_ioctl+0x417/0xca0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2698 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0x75a/0xff0 fs/ioctl.c:684 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7f95f37525a9 RSP: 002b:00007f95f20c5168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f95f3872f80 RCX: 00007f95f37525a9 RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000008 RBP: 00007f95f37ad580 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fff0a343d3f R14: 00007f95f20c5300 R15: 0000000000022000 Code: 81 48 01 d8 c7 00 f1 f1 f1 f1 c7 40 04 00 f3 f3 f3 e8 37 d1 40 00 48 89 ef e8 af 97 10 00 48 89 44 24 20 48 8d 44 24 20 0f c7 30 05 e8 5b 39 f4 ff 0f 96 c0 84 c0 0f 85 bc c8 ec 05 e8 0b d1