INFO: task syz-executor.2:15088 can't die for more than 143 seconds. task:syz-executor.2 state:D stack:28112 pid:15088 ppid: 3612 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:4986 [inline] __schedule+0xab2/0x4e90 kernel/sched/core.c:6296 schedule+0xd2/0x260 kernel/sched/core.c:6369 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6428 __mutex_lock_common kernel/locking/mutex.c:673 [inline] __mutex_lock+0xa32/0x12f0 kernel/locking/mutex.c:733 vhost_net_stop_vq drivers/vhost/net.c:1359 [inline] vhost_net_stop+0x142/0x270 drivers/vhost/net.c:1373 vhost_net_release+0x9c/0x2d0 drivers/vhost/net.c:1405 __fput+0x286/0x9f0 fs/file_table.c:311 task_work_run+0xdd/0x1a0 kernel/task_work.c:164 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_user_mode_loop kernel/entry/common.c:175 [inline] exit_to_user_mode_prepare+0x27e/0x290 kernel/entry/common.c:207 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:300 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f2321e8fc2b RSP: 002b:00007ffe2840e700 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000004 RCX: 00007f2321e8fc2b RDX: 00007f2321ff4690 RSI: ffffffffffffffff RDI: 0000000000000003 RBP: 00007f2321ff1960 R08: 0000000000000000 R09: 00007f2321ff4698 R10: 00007ffe2840e800 R11: 0000000000000293 R12: 00000000000223a9 R13: 00007ffe2840e800 R14: 00007f2321feff60 R15: 0000000000000032 INFO: task syz-executor.2:15088 blocked for more than 143 seconds. Not tainted 5.16.0-next-20220117-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.2 state:D stack:28112 pid:15088 ppid: 3612 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:4986 [inline] __schedule+0xab2/0x4e90 kernel/sched/core.c:6296 schedule+0xd2/0x260 kernel/sched/core.c:6369 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6428 __mutex_lock_common kernel/locking/mutex.c:673 [inline] __mutex_lock+0xa32/0x12f0 kernel/locking/mutex.c:733 vhost_net_stop_vq drivers/vhost/net.c:1359 [inline] vhost_net_stop+0x142/0x270 drivers/vhost/net.c:1373 vhost_net_release+0x9c/0x2d0 drivers/vhost/net.c:1405 __fput+0x286/0x9f0 fs/file_table.c:311 task_work_run+0xdd/0x1a0 kernel/task_work.c:164 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_user_mode_loop kernel/entry/common.c:175 [inline] exit_to_user_mode_prepare+0x27e/0x290 kernel/entry/common.c:207 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:300 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f2321e8fc2b RSP: 002b:00007ffe2840e700 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000004 RCX: 00007f2321e8fc2b RDX: 00007f2321ff4690 RSI: ffffffffffffffff RDI: 0000000000000003 RBP: 00007f2321ff1960 R08: 0000000000000000 R09: 00007f2321ff4698 R10: 00007ffe2840e800 R11: 0000000000000293 R12: 00000000000223a9 R13: 00007ffe2840e800 R14: 00007f2321feff60 R15: 0000000000000032 Showing all locks held in the system: 1 lock held by khungtaskd/26: #0: ffffffff8bb83520 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6460 2 locks held by getty/3281: #0: ffff88814ac4a098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:244 #1: ffffc90002b632e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xcf0/0x1230 drivers/tty/n_tty.c:2077 1 lock held by syz-executor.2/15088: #0: ffff888074670218 (&vq->mutex){+.+.}-{3:3}, at: vhost_net_stop_vq drivers/vhost/net.c:1359 [inline] #0: ffff888074670218 (&vq->mutex){+.+.}-{3:3}, at: vhost_net_stop+0x142/0x270 drivers/vhost/net.c:1373 1 lock held by vhost-15089/15091: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 26 Comm: khungtaskd Not tainted 5.16.0-next-20220117-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:256 [inline] watchdog+0xcb7/0xed0 kernel/hung_task.c:413 kthread+0x2e9/0x3a0 kernel/kthread.c:377 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 15091 Comm: vhost-15089 Not tainted 5.16.0-next-20220117-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:check_kcov_mode+0x2e/0x40 kernel/kcov.c:177 Code: 16 8a 7e 89 c2 81 e2 00 01 00 00 a9 00 01 ff 00 74 10 31 c0 85 d2 74 15 8b 96 ac 15 00 00 85 d2 74 0b 8b 86 88 15 00 00 39 f8 <0f> 94 c0 c3 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 31 c0 65 8b RSP: 0018:ffffc90002e0fae8 EFLAGS: 00000297 RAX: 0000000000000002 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffff8880581cd7c0 RDI: 0000000000000003 RBP: 0000000000000000 R08: 000000000000000f R09: ffff8880746701bb R10: ffffffff86e2bd94 R11: 0000000000000001 R12: ffff8880190a2100 R13: 000000000000000f R14: ffffffffffffffff R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f382b39ac68 CR3: 00000000558a0000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: write_comp_data kernel/kcov.c:221 [inline] __sanitizer_cov_trace_cmp8+0x1d/0x70 kernel/kcov.c:267 vhost_iotlb_itree_iter_first drivers/vhost/iotlb.c:19 [inline] vhost_iotlb_itree_first+0xd4/0x280 drivers/vhost/iotlb.c:169 iotlb_access_ok+0x1ce/0x3e0 drivers/vhost/vhost.c:1336 vq_meta_prefetch+0xbc/0x280 drivers/vhost/vhost.c:1366 handle_rx+0x145/0x1b40 drivers/vhost/net.c:1140 vhost_worker+0x23d/0x3d0 drivers/vhost/vhost.c:372 kthread+0x2e9/0x3a0 kernel/kthread.c:377 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 ---------------- Code disassembly (best guess), 1 bytes skipped: 0: 8a 7e 89 mov -0x77(%rsi),%bh 3: c2 81 e2 retq $0xe281 6: 00 01 add %al,(%rcx) 8: 00 00 add %al,(%rax) a: a9 00 01 ff 00 test $0xff0100,%eax f: 74 10 je 0x21 11: 31 c0 xor %eax,%eax 13: 85 d2 test %edx,%edx 15: 74 15 je 0x2c 17: 8b 96 ac 15 00 00 mov 0x15ac(%rsi),%edx 1d: 85 d2 test %edx,%edx 1f: 74 0b je 0x2c 21: 8b 86 88 15 00 00 mov 0x1588(%rsi),%eax 27: 39 f8 cmp %edi,%eax * 29: 0f 94 c0 sete %al <-- trapping instruction 2c: c3 retq 2d: 66 66 2e 0f 1f 84 00 data16 nopw %cs:0x0(%rax,%rax,1) 34: 00 00 00 00 38: 0f 1f 00 nopl (%rax) 3b: 31 c0 xor %eax,%eax 3d: 65 gs 3e: 8b .byte 0x8b