syzbot


INFO: task hung in nbd_add_socket

Status: closed as dup on 2021/11/21 13:59
Subsystems: block
[Documentation on labels]
Reported-by: syzbot+77c541b705f80d3415bd@syzkaller.appspotmail.com
First crash: 954d, last: 860d
Duplicate of
Title Repro Cause bisect Fix bisect Count Last Reported
INFO: task can't die in blk_mq_freeze_queue_wait block 221 937d 945d
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] INFO: task hung in nbd_add_socket 0 (1) 2021/11/20 08:57
Similar bugs (6)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in nbd_add_socket (2) block C error 36 35d 818d 0/27 upstream: reported C repro on 2022/03/21 16:06
linux-4.14 INFO: task hung in nbd_add_socket (2) C error 2 651d 904d 0/1 upstream: reported C repro on 2021/12/25 23:00
linux-4.14 INFO: task hung in nbd_add_socket 1 1196d 1196d 0/1 auto-closed as invalid on 2021/07/06 19:04
linux-4.19 INFO: task hung in nbd_add_socket C error 11 473d 1196d 0/1 upstream: reported C repro on 2021/03/08 23:07
linux-6.1 INFO: task hung in nbd_add_socket origin:upstream C 2 20d 392d 0/3 upstream: reported C repro on 2023/05/21 19:27
upstream INFO: task can't die in blk_mq_freeze_queue_wait block 221 937d 945d 20/27 fixed on 2022/03/08 16:11

Sample crash report:
INFO: task syz-executor.3:19132 blocked for more than 143 seconds.
      Not tainted 5.17.0-rc2-syzkaller-00398-gd8ad2ce873ab #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.3  state:D stack:28512 pid:19132 ppid:  3622 flags:0x00000004
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
 blk_mq_freeze_queue_wait+0x112/0x160 block/blk-mq.c:178
 nbd_add_socket+0x166/0x810 drivers/block/nbd.c:1109
 __nbd_ioctl drivers/block/nbd.c:1454 [inline]
 nbd_ioctl+0x38c/0xb10 drivers/block/nbd.c:1511
 blkdev_ioctl+0x37a/0x800 block/ioctl.c:588
 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: 0033:0x7f3a2fd75059
RSP: 002b:00007f3a2e6a8168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f3a2fe88100 RCX: 00007f3a2fd75059
RDX: 0000000000000006 RSI: 000000000000ab00 RDI: 0000000000000003
RBP: 00007f3a2fdcf08d R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fff2b26772f R14: 00007f3a2e6a8300 R15: 0000000000022000
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/27:
 #0: ffffffff8bb83c20 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6460
2 locks held by kworker/u4:4/999:
 #0: ffff8880b9d39c58 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2b/0x120 kernel/sched/core.c:489
 #1: ffff8880b9d27948 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x3e7/0x4e0 kernel/sched/psi.c:891
2 locks held by getty/3276:
 #0: ffff88802303f098 (&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.3/19132:
 #0: ffff88801a753998 (&nbd->config_lock){+.+.}-{3:3}, at: nbd_ioctl+0x151/0xb10 drivers/block/nbd.c:1504

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

NMI backtrace for cpu 0
CPU: 0 PID: 27 Comm: khungtaskd Not tainted 5.17.0-rc2-syzkaller-00398-gd8ad2ce873ab #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 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 8389 Comm: kworker/u4:18 Not tainted 5.17.0-rc2-syzkaller-00398-gd8ad2ce873ab #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet
RIP: 0010:lock_acquire+0x69/0x510 kernel/locking/lockdep.c:5607
Code: 03 48 c7 44 24 18 12 d6 39 8b 48 01 d8 48 c7 44 24 20 50 5a 5d 81 c7 00 f1 f1 f1 f1 c7 40 04 f1 f1 00 00 c7 40 08 00 00 00 f3 <c7> 40 0c f3 f3 f3 f3 65 48 8b 04 25 28 00 00 00 48 89 84 24 a8 00
RSP: 0018:ffffc9000499fab0 EFLAGS: 00000282
RAX: fffff52000933f58 RBX: 1ffff92000933f58 RCX: 0000000000000002
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8bb83c20
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff88e1b846 R11: 0000000000000000 R12: 0000000000000002
R13: 0000000000000000 R14: ffffffff8bb83c20 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c000041da8 CR3: 0000000071913000 CR4: 0000000000350ee0
Call Trace:
 <TASK>
 rcu_lock_acquire include/linux/rcupdate.h:268 [inline]
 rcu_read_lock include/linux/rcupdate.h:694 [inline]
 batadv_iv_ogm_slide_own_bcast_window net/batman-adv/bat_iv_ogm.c:755 [inline]
 batadv_iv_ogm_schedule_buff+0x5d2/0x1430 net/batman-adv/bat_iv_ogm.c:826
 batadv_iv_ogm_schedule net/batman-adv/bat_iv_ogm.c:869 [inline]
 batadv_iv_ogm_schedule net/batman-adv/bat_iv_ogm.c:862 [inline]
 batadv_iv_send_outstanding_bat_ogm_packet+0x740/0x910 net/batman-adv/bat_iv_ogm.c:1713
 process_one_work+0x9ac/0x1650 kernel/workqueue.c:2307
 worker_thread+0x657/0x1110 kernel/workqueue.c:2454
 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:	03 48 c7             	add    -0x39(%rax),%ecx
   3:	44 24 18             	rex.R and $0x18,%al
   6:	12 d6                	adc    %dh,%dl
   8:	39 8b 48 01 d8 48    	cmp    %ecx,0x48d80148(%rbx)
   e:	c7 44 24 20 50 5a 5d 	movl   $0x815d5a50,0x20(%rsp)
  15:	81
  16:	c7 00 f1 f1 f1 f1    	movl   $0xf1f1f1f1,(%rax)
  1c:	c7 40 04 f1 f1 00 00 	movl   $0xf1f1,0x4(%rax)
  23:	c7 40 08 00 00 00 f3 	movl   $0xf3000000,0x8(%rax)
* 2a:	c7 40 0c f3 f3 f3 f3 	movl   $0xf3f3f3f3,0xc(%rax) <-- trapping instruction
  31:	65 48 8b 04 25 28 00 	mov    %gs:0x28,%rax
  38:	00 00
  3a:	48                   	rex.W
  3b:	89                   	.byte 0x89
  3c:	84 24 a8             	test   %ah,(%rax,%rbp,4)

Crashes (75):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/02/07 10:42 upstream d8ad2ce873ab a7dab638 .config console log report info ci-upstream-kasan-gce-root INFO: task hung in nbd_add_socket
2022/01/24 01:50 upstream dd81e1c7d5fb 214351e1 .config console log report info ci-upstream-kasan-gce-root INFO: task hung in nbd_add_socket
2021/11/21 02:45 upstream a90af8f15bdc 4eb20a4e .config console log report info ci-upstream-kasan-gce-root INFO: task hung in nbd_add_socket
2021/11/21 00:38 upstream a90af8f15bdc 4eb20a4e .config console log report info ci-upstream-kasan-gce-smack-root INFO: task hung in nbd_add_socket
2021/11/20 14:54 upstream a90af8f15bdc 4eb20a4e .config console log report info ci-upstream-kasan-gce-root INFO: task hung in nbd_add_socket
2021/11/20 07:20 upstream 9539ba4308ad 3a9d0024 .config console log report info ci-upstream-kasan-gce-root INFO: task hung in nbd_add_socket
2021/11/19 22:35 upstream 9539ba4308ad 3a9d0024 .config console log report info ci-upstream-kasan-gce-root INFO: task hung in nbd_add_socket
2021/11/19 20:46 upstream 9539ba4308ad 3a9d0024 .config console log report info ci-upstream-kasan-gce-root INFO: task hung in nbd_add_socket
2021/11/19 17:10 upstream 4c388a8e740d 3a9d0024 .config console log report info ci-upstream-kasan-gce-root INFO: task hung in nbd_add_socket
2021/11/19 16:00 upstream 4c388a8e740d 3a9d0024 .config console log report info ci-upstream-kasan-gce-root INFO: task hung in nbd_add_socket
2021/11/19 14:53 upstream 4c388a8e740d 3a9d0024 .config console log report info ci-upstream-kasan-gce-root INFO: task hung in nbd_add_socket
2021/11/19 09:31 upstream 4c388a8e740d 31a30fc0 .config console log report info ci-upstream-kasan-gce-root INFO: task hung in nbd_add_socket
2021/11/19 06:23 upstream 4c388a8e740d 31a30fc0 .config console log report info ci-upstream-kasan-gce-root INFO: task hung in nbd_add_socket
2021/11/19 03:24 upstream 4c388a8e740d 31a30fc0 .config console log report info ci-upstream-kasan-gce-root INFO: task hung in nbd_add_socket
2021/11/18 22:16 upstream 6fdf886424cf 31a30fc0 .config console log report info ci-upstream-kasan-gce-smack-root INFO: task hung in nbd_add_socket
2021/11/18 19:43 upstream 42eb8fdac2fc 31a30fc0 .config console log report info ci-upstream-kasan-gce-smack-root INFO: task hung in nbd_add_socket
2021/11/18 16:17 upstream 42eb8fdac2fc 31a30fc0 .config console log report info ci-upstream-kasan-gce-root INFO: task hung in nbd_add_socket
2021/11/18 09:23 upstream 42eb8fdac2fc cafff8b6 .config console log report info ci-upstream-kasan-gce-smack-root INFO: task hung in nbd_add_socket
2021/11/17 19:48 upstream ee1703cda8dc cafff8b6 .config console log report info ci-upstream-kasan-gce-root INFO: task hung in nbd_add_socket
2021/11/17 18:04 upstream ee1703cda8dc cafff8b6 .config console log report info ci-upstream-kasan-gce-root INFO: task hung in nbd_add_socket
2021/11/17 17:58 upstream ee1703cda8dc cafff8b6 .config console log report info ci-upstream-kasan-gce-smack-root INFO: task hung in nbd_add_socket
2021/11/17 11:35 upstream 8ab774587903 cafff8b6 .config console log report info ci-upstream-kasan-gce-root INFO: task hung in nbd_add_socket
2021/11/17 07:44 upstream 8ab774587903 cafff8b6 .config console log report info ci-upstream-kasan-gce-root INFO: task hung in nbd_add_socket
2021/11/17 00:55 upstream 8ab774587903 cafff8b6 .config console log report info ci-upstream-kasan-gce-root INFO: task hung in nbd_add_socket
2021/11/17 00:53 upstream 8ab774587903 cafff8b6 .config console log report info ci-upstream-kasan-gce-root INFO: task hung in nbd_add_socket
2021/11/16 23:13 upstream 8ab774587903 cafff8b6 .config console log report info ci-upstream-kasan-gce-root INFO: task hung in nbd_add_socket
2021/11/16 22:34 upstream 8ab774587903 cafff8b6 .config console log report info ci-upstream-kasan-gce-root INFO: task hung in nbd_add_socket
2021/11/16 13:23 upstream 8ab774587903 600426bd .config console log report info ci-upstream-kasan-gce-root INFO: task hung in nbd_add_socket
2021/11/16 12:31 upstream 8ab774587903 600426bd .config console log report info ci-upstream-kasan-gce-selinux-root INFO: task hung in nbd_add_socket
2021/11/16 10:54 upstream 8ab774587903 600426bd .config console log report info ci-upstream-kasan-gce-root INFO: task hung in nbd_add_socket
2021/11/16 08:40 upstream 8ab774587903 83f5c9b5 .config console log report info ci-upstream-kasan-gce-root INFO: task hung in nbd_add_socket
2021/11/16 05:28 upstream 8ab774587903 83f5c9b5 .config console log report info ci-upstream-kasan-gce-root INFO: task hung in nbd_add_socket
2021/11/16 00:12 upstream 8ab774587903 83f5c9b5 .config console log report info ci-upstream-kasan-gce-selinux-root INFO: task hung in nbd_add_socket
2021/11/16 00:07 upstream 8ab774587903 83f5c9b5 .config console log report info ci-upstream-kasan-gce-root INFO: task hung in nbd_add_socket
2021/11/15 18:56 upstream 8ab774587903 83f5c9b5 .config console log report info ci-upstream-kasan-gce-root INFO: task hung in nbd_add_socket
2021/11/15 18:26 upstream 8ab774587903 83f5c9b5 .config console log report info ci-upstream-kasan-gce-root INFO: task hung in nbd_add_socket
2021/11/15 17:10 upstream 8ab774587903 83f5c9b5 .config console log report info ci-upstream-kasan-gce-root INFO: task hung in nbd_add_socket
2021/11/15 16:39 upstream 8ab774587903 83f5c9b5 .config console log report info ci-upstream-kasan-gce-root INFO: task hung in nbd_add_socket
2021/11/15 07:37 upstream fa55b7dcdc43 83f5c9b5 .config console log report info ci-upstream-kasan-gce-root INFO: task hung in nbd_add_socket
2021/11/15 05:31 upstream fa55b7dcdc43 83f5c9b5 .config console log report info ci-upstream-kasan-gce-root INFO: task hung in nbd_add_socket
2021/11/15 05:22 upstream fa55b7dcdc43 83f5c9b5 .config console log report info ci-upstream-kasan-gce-root INFO: task hung in nbd_add_socket
2021/11/15 04:43 upstream fa55b7dcdc43 83f5c9b5 .config console log report info ci-upstream-kasan-gce-root INFO: task hung in nbd_add_socket
2021/11/15 03:34 upstream fa55b7dcdc43 83f5c9b5 .config console log report info ci-upstream-kasan-gce-root INFO: task hung in nbd_add_socket
2021/11/15 03:22 upstream fa55b7dcdc43 83f5c9b5 .config console log report info ci-upstream-kasan-gce-root INFO: task hung in nbd_add_socket
2021/11/14 23:32 upstream c8c109546a19 83f5c9b5 .config console log report info ci-upstream-kasan-gce-root INFO: task hung in nbd_add_socket
2021/11/14 22:26 upstream c8c109546a19 83f5c9b5 .config console log report info ci-upstream-kasan-gce-root INFO: task hung in nbd_add_socket
2021/11/14 19:05 upstream c8c109546a19 83f5c9b5 .config console log report info ci-upstream-kasan-gce-root INFO: task hung in nbd_add_socket
2021/11/14 15:52 upstream c8c109546a19 83f5c9b5 .config console log report info ci-upstream-kasan-gce-smack-root INFO: task hung in nbd_add_socket
2021/11/14 14:58 upstream c8c109546a19 83f5c9b5 .config console log report info ci-upstream-kasan-gce-root INFO: task hung in nbd_add_socket
2021/11/14 14:43 upstream c8c109546a19 83f5c9b5 .config console log report info ci-upstream-kasan-gce-root INFO: task hung in nbd_add_socket
2021/11/14 14:32 upstream c8c109546a19 83f5c9b5 .config console log report info ci-upstream-kasan-gce-root INFO: task hung in nbd_add_socket
2021/11/14 14:14 upstream c8c109546a19 83f5c9b5 .config console log report info ci-upstream-kasan-gce-smack-root INFO: task hung in nbd_add_socket
2021/11/14 14:14 upstream c8c109546a19 83f5c9b5 .config console log report info ci-upstream-kasan-gce-root INFO: task hung in nbd_add_socket
2021/11/14 13:41 upstream c8c109546a19 83f5c9b5 .config console log report info ci-upstream-kasan-gce-root INFO: task hung in nbd_add_socket
2021/11/14 11:40 upstream ccfff0a2bd2a 83f5c9b5 .config console log report info ci-upstream-kasan-gce-root INFO: task hung in nbd_add_socket
2021/11/14 10:35 upstream ccfff0a2bd2a 83f5c9b5 .config console log report info ci-upstream-kasan-gce-root INFO: task hung in nbd_add_socket
2021/11/14 09:31 upstream c8c109546a19 83f5c9b5 .config console log report info ci-upstream-kasan-gce-selinux-root INFO: task hung in nbd_add_socket
2021/11/14 09:18 upstream ccfff0a2bd2a 83f5c9b5 .config console log report info ci-upstream-kasan-gce-root INFO: task hung in nbd_add_socket
2021/11/14 01:36 upstream ccfff0a2bd2a 83f5c9b5 .config console log report info ci-upstream-kasan-gce-root INFO: task hung in nbd_add_socket
2021/11/06 07:09 upstream fe91c4725aee 4c1be0be .config console log report info ci-upstream-kasan-gce-smack-root INFO: task hung in nbd_add_socket
2021/11/22 15:08 linux-next 5191249f8803 545ab074 .config console log report info ci-upstream-linux-next-kasan-gce-root INFO: task hung in nbd_add_socket
* Struck through repros no longer work on HEAD.