syzbot


INFO: task hung in vhost_vsock_dev_ioctl

Status: auto-closed as invalid on 2022/05/10 09:51
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 293d, last: 293d

Sample crash report:
INFO: task syz-executor.5:4186 blocked for more than 143 seconds.
      Not tainted 5.17.0-rc3-syzkaller-00029-ge6251ab4551f #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.5  state:D stack:29096 pid: 4186 ppid:  3628 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:4986 [inline]
 __schedule+0xab2/0x4db0 kernel/sched/core.c:6295
 schedule+0xd2/0x260 kernel/sched/core.c:6368
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6427
 __mutex_lock_common kernel/locking/mutex.c:673 [inline]
 __mutex_lock+0xa32/0x12f0 kernel/locking/mutex.c:733
 vhost_vsock_dev_ioctl+0x377/0xbc0 drivers/vhost/vsock.c:894
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl fs/ioctl.c:860 [inline]
 __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:860
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7fefd15ad059
RSP: 002b:00007fefcff22168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fefd16bff60 RCX: 00007fefd15ad059
RDX: 0000000020000780 RSI: 000000004028af11 RDI: 0000000000000031
RBP: 00007fefd160708d R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffd009d891f R14: 00007fefcff22300 R15: 0000000000022000
 </TASK>
INFO: task syz-executor.5:4187 blocked for more than 143 seconds.
      Not tainted 5.17.0-rc3-syzkaller-00029-ge6251ab4551f #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.5  state:D stack:29080 pid: 4187 ppid:  3628 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:4986 [inline]
 __schedule+0xab2/0x4db0 kernel/sched/core.c:6295
 schedule+0xd2/0x260 kernel/sched/core.c:6368
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6427
 __mutex_lock_common kernel/locking/mutex.c:673 [inline]
 __mutex_lock+0xa32/0x12f0 kernel/locking/mutex.c:733
 vhost_vsock_start drivers/vhost/vsock.c:582 [inline]
 vhost_vsock_dev_ioctl+0x24b/0xbc0 drivers/vhost/vsock.c:869
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl fs/ioctl.c:860 [inline]
 __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:860
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7fefd15ad059
RSP: 002b:00007fefcff01168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fefd16c0030 RCX: 00007fefd15ad059
RDX: 0000000020000000 RSI: 000000004004af61 RDI: 0000000000000031
RBP: 00007fefd160708d R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffd009d891f R14: 00007fefcff01300 R15: 0000000000022000
 </TASK>
INFO: task syz-executor.5:4188 blocked for more than 144 seconds.
      Not tainted 5.17.0-rc3-syzkaller-00029-ge6251ab4551f #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.5  state:D stack:29048 pid: 4188 ppid:  3628 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:4986 [inline]
 __schedule+0xab2/0x4db0 kernel/sched/core.c:6295
 schedule+0xd2/0x260 kernel/sched/core.c:6368
 schedule_timeout+0x1db/0x2a0 kernel/time/timer.c:1857
 do_wait_for_common kernel/sched/completion.c:85 [inline]
 __wait_for_common kernel/sched/completion.c:106 [inline]
 wait_for_common kernel/sched/completion.c:117 [inline]
 wait_for_completion+0x174/0x270 kernel/sched/completion.c:138
 vhost_work_dev_flush.part.0+0xbb/0xf0 drivers/vhost/vhost.c:243
 vhost_work_dev_flush drivers/vhost/vhost.c:238 [inline]
 vhost_poll_flush+0x5e/0x80 drivers/vhost/vhost.c:252
 vhost_vsock_flush drivers/vhost/vsock.c:710 [inline]
 vhost_vsock_dev_ioctl+0x3e9/0xbc0 drivers/vhost/vsock.c:899
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl fs/ioctl.c:860 [inline]
 __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:860
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7fefd15ad059
RSP: 002b:00007fefcfee0168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fefd16c0100 RCX: 00007fefd15ad059
RDX: 0000000000000000 RSI: 000000000000af01 RDI: 0000000000000031
RBP: 00007fefd160708d R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffd009d891f R14: 00007fefcfee0300 R15: 0000000000022000
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/26:
 #0: ffffffff8bb81120 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6460
2 locks held by getty/3281:
 #0: ffff88802549e098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:244
 #1: ffffc90002b5e2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xcf0/0x1230 drivers/tty/n_tty.c:2077
1 lock held by syz-executor.5/4186:
 #0: ffff88802e220070 (&dev->mutex#4){+.+.}-{3:3}, at: vhost_vsock_dev_ioctl+0x377/0xbc0 drivers/vhost/vsock.c:894
1 lock held by syz-executor.5/4187:
 #0: ffff88802e220070 (&dev->mutex#4){+.+.}-{3:3}, at: vhost_vsock_start drivers/vhost/vsock.c:582 [inline]
 #0: ffff88802e220070 (&dev->mutex#4){+.+.}-{3:3}, at: vhost_vsock_dev_ioctl+0x24b/0xbc0 drivers/vhost/vsock.c:869
1 lock held by syz-executor.5/4188:
 #0: ffff88802e220070 (&dev->mutex#4){+.+.}-{3:3}, at: vhost_vsock_dev_ioctl+0x377/0xbc0 drivers/vhost/vsock.c:894
1 lock held by vhost-4188/4189:

=============================================

NMI backtrace for cpu 1
CPU: 1 PID: 26 Comm: khungtaskd Not tainted 5.17.0-rc3-syzkaller-00029-ge6251ab4551f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <TASK>
 __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:212 [inline]
 watchdog+0xc1d/0xf50 kernel/hung_task.c:369
 kthread+0x2e9/0x3a0 kernel/kthread.c:377
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 4189 Comm: vhost-4188 Not tainted 5.17.0-rc3-syzkaller-00029-ge6251ab4551f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:check_kcov_mode+0x2c/0x40 kernel/kcov.c:177
Code: 05 29 c6 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 a4 15 00 00 85 d2 74 0b 8b 86 80 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
RSP: 0018:ffffc9001065fc38 EFLAGS: 00000246
RAX: 0000000000000002 RBX: 0000000000000000 RCX: ffffffffffffffff
RDX: 0000000000000000 RSI: ffff888026788140 RDI: 0000000000000003
RBP: dffffc0000000000 R08: 0000000000000000 R09: ffffc9001065fc77
R10: ffffffff86d4cd0d R11: 0000000000000001 R12: ffff888072db2300
R13: 000000000000000f R14: ffffffffffffffff R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f93c5e54600 CR3: 000000007581e000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 write_comp_data kernel/kcov.c:221 [inline]
 __sanitizer_cov_trace_cmp8+0x1d/0x70 kernel/kcov.c:267
 vhost_iotlb_itree_subtree_search drivers/vhost/iotlb.c:19 [inline]
 vhost_iotlb_itree_iter_first drivers/vhost/iotlb.c:19 [inline]
 vhost_iotlb_itree_first+0x19d/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
 vhost_transport_do_send_pkt+0xe0/0xfd0 drivers/vhost/vsock.c:104
 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
 </TASK>
----------------
Code disassembly (best guess):
   0:	05 29 c6 8a 7e       	add    $0x7e8ac629,%eax
   5:	89 c2                	mov    %eax,%edx
   7:	81 e2 00 01 00 00    	and    $0x100,%edx
   d:	a9 00 01 ff 00       	test   $0xff0100,%eax
  12:	74 10                	je     0x24
  14:	31 c0                	xor    %eax,%eax
  16:	85 d2                	test   %edx,%edx
  18:	74 15                	je     0x2f
  1a:	8b 96 a4 15 00 00    	mov    0x15a4(%rsi),%edx
  20:	85 d2                	test   %edx,%edx
  22:	74 0b                	je     0x2f
  24:	8b 86 80 15 00 00    	mov    0x1580(%rsi),%eax
* 2a:	39 f8                	cmp    %edi,%eax <-- trapping instruction
  2c:	0f 94 c0             	sete   %al
  2f:	c3                   	retq
  30:	66 66 2e 0f 1f 84 00 	data16 nopw %cs:0x0(%rax,%rax,1)
  37:	00 00 00 00
  3b:	0f 1f 00             	nopl   (%rax)
  3e:	31 c0                	xor    %eax,%eax

Crashes (1):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci-upstream-kasan-gce-selinux-root 2022/02/09 09:48 upstream e6251ab4551f 0b33604d .config log report info INFO: task hung in vhost_vsock_dev_ioctl
* Struck through repros no longer work on HEAD.