syzbot


INFO: task hung in __blkdev_get

Status: public: reported C repro on 2019/04/12 00:00
Reported-by: syzbot+ea035c20286692c41efe@syzkaller.appspotmail.com
First crash: 2310d, last: 1581d
Similar bugs (9)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-44 INFO: task hung in __blkdev_get syz 521 1583d 1811d 0/2 public: reported syz repro on 2019/04/14 00:02
android-414 INFO: task hung in __blkdev_get 1859 1580d 1812d 0/1 auto-closed as invalid on 2020/02/28 16:13
upstream INFO: task hung in __blkdev_get (3) fs 1 1806d 1806d 0/26 closed as invalid on 2019/05/08 13:05
upstream INFO: task hung in __blkdev_get (2) udf 11 1905d 2028d 0/26 closed as dup on 2018/09/08 15:48
linux-4.14 INFO: task hung in __blkdev_get ntfs vfs C 741 402d 1814d 0/1 upstream: reported C repro on 2019/04/11 13:17
upstream INFO: task hung in __blkdev_get fs C 662 2176d 2302d 5/26 fixed on 2018/05/08 18:30
linux-4.19 INFO: task hung in __blkdev_get vfs ntfs C error 144 396d 1690d 0/1 upstream: reported C repro on 2019/08/13 00:10
upstream INFO: task hung in __blkdev_get (4) fs 1 1625d 1625d 0/26 auto-closed as invalid on 2020/01/15 05:33
upstream INFO: task hung in __blkdev_get (5) fs 8 1204d 1418d 0/26 auto-closed as invalid on 2021/03/11 14:46

Sample crash report:
random: crng init done
INFO: task blkid:3373 blocked for more than 120 seconds.
      Not tainted 4.9.66-gb763480 #103
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
blkid           D28208  3373   1866 0x00000004
 ffff8801cefb8000 0000000000000000 ffff8801cd990540 ffff8801da29b000
 ffff8801db321418 ffff8801ca087708 ffffffff838981cb 0000000000000000
 0000000000000007 00ff8801cefb8000 ffff8801db321ce8 ffff8801db321d10
Call Trace:
 [<ffffffff8389976f>] schedule+0x7f/0x1b0 kernel/sched/core.c:3550
 [<ffffffff8389a0f3>] schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3583
 [<ffffffff8389f702>] __mutex_lock_common kernel/locking/mutex.c:582 [inline]
 [<ffffffff8389f702>] mutex_lock_nested+0x312/0x870 kernel/locking/mutex.c:621
 [<ffffffff8162a23c>] __blkdev_get+0x10c/0xd50 fs/block_dev.c:1268
 [<ffffffff8162c10b>] blkdev_get+0x33b/0x960 fs/block_dev.c:1416
 [<ffffffff8162c935>] blkdev_open+0x1a5/0x250 fs/block_dev.c:1571
 [<ffffffff81563227>] do_dentry_open+0x607/0xc60 fs/open.c:766
 [<ffffffff81566cd5>] vfs_open+0x105/0x220 fs/open.c:879
 [<ffffffff8159d44c>] do_last fs/namei.c:3408 [inline]
 [<ffffffff8159d44c>] path_openat+0x5ac/0x2910 fs/namei.c:3531
 [<ffffffff815a2fa7>] do_filp_open+0x197/0x290 fs/namei.c:3566
 [<ffffffff815677b2>] do_sys_open+0x352/0x4c0 fs/open.c:1072
 [<ffffffff8156794d>] SYSC_open fs/open.c:1090 [inline]
 [<ffffffff8156794d>] SyS_open+0x2d/0x40 fs/open.c:1085
 [<ffffffff838a9985>] entry_SYSCALL_64_fastpath+0x23/0xc6

Showing all locks held in the system:
2 locks held by khungtaskd/514:
 #0:  (rcu_read_lock){......}, at: [<ffffffff8136fe05>] check_hung_uninterruptible_tasks kernel/hung_task.c:168 [inline]
 #0:  (rcu_read_lock){......}, at: [<ffffffff8136fe05>] watchdog+0x125/0xa70 kernel/hung_task.c:239
 #1:  (tasklist_lock){.+.+..}, at: [<ffffffff812355d0>] debug_show_all_locks+0x70/0x280 kernel/locking/lockdep.c:4336
1 lock held by rsyslogd/3150:
 #0:  (&f->f_pos_lock){+.+.+.}, at: [<ffffffff815cf91f>] __fdget_pos+0x9f/0xc0 fs/file.c:781
2 locks held by getty/3238:
 #0:  (&tty->ldisc_sem){++++++}, at: [<ffffffff838a7b92>] ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:367
 #1:  (&ldata->atomic_read_lock){+.+...}, at: [<ffffffff82001d84>] n_tty_read+0x1f4/0x16c0 drivers/tty/n_tty.c:2133
1 lock held by syzkaller946102/3370:
 #0:  (&bdev->bd_mutex){+.+.+.}, at: [<ffffffff81629a0c>] __blkdev_put+0xbc/0x7e0 fs/block_dev.c:1579
1 lock held by blkid/3373:
 #0:  (&bdev->bd_mutex){+.+.+.}, at: [<ffffffff8162a23c>] __blkdev_get+0x10c/0xd50 fs/block_dev.c:1268

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

NMI backtrace for cpu 0
CPU: 0 PID: 514 Comm: khungtaskd Not tainted 4.9.66-gb763480 #103
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801d99dfd00 ffffffff81d90749 0000000000000000 0000000000000000
 0000000000000000 0000000000000001 ffffffff810ba170 ffff8801d99dfd38
 ffffffff81d9b86d 0000000000000000 0000000000000000 ffff8801cefb8418
Call Trace:
 [<ffffffff81d90749>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81d90749>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff81d9b86d>] nmi_cpu_backtrace+0xfd/0x120 lib/nmi_backtrace.c:99
 [<ffffffff81d9b9a7>] nmi_trigger_cpumask_backtrace+0x117/0x190 lib/nmi_backtrace.c:60
 [<ffffffff810ba264>] arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:37
 [<ffffffff813703d0>] trigger_all_cpu_backtrace include/linux/nmi.h:58 [inline]
 [<ffffffff813703d0>] check_hung_task kernel/hung_task.c:125 [inline]
 [<ffffffff813703d0>] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline]
 [<ffffffff813703d0>] watchdog+0x6f0/0xa70 kernel/hung_task.c:239
 [<ffffffff811985ad>] kthread+0x26d/0x300 kernel/kthread.c:211
 [<ffffffff838a9c2a>] ret_from_fork+0x2a/0x40 arch/x86/entry/entry_64.S:437
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1 skipped: idling at pc 0xffffffff838a8606

Crashes (1504):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2017/12/03 21:23 https://android.googlesource.com/kernel/common android-4.9 b76348094703 48359b97 .config console log report syz C ci-android-49-kasan-gce
2019/11/30 13:54 android-4.9 a36b5017c810 3a75be00 .config console log report ci-android-49-kasan-gce-root
2019/11/29 11:45 android-4.9 a36b5017c810 d29b9e84 .config console log report ci-android-49-kasan-gce-root
2019/11/24 05:16 android-4.9 258971b8e1ac 598ca6c8 .config console log report ci-android-49-kasan-gce-root
2019/11/14 07:54 https://android.googlesource.com/kernel/common android-4.9 7fe05eede1c8 048f2d49 .config console log report ci-android-49-kasan-gce-root
2019/11/14 04:33 https://android.googlesource.com/kernel/common android-4.9 7fe05eede1c8 048f2d49 .config console log report ci-android-49-kasan-gce-root
2019/11/14 01:34 https://android.googlesource.com/kernel/common android-4.9 7fe05eede1c8 048f2d49 .config console log report ci-android-49-kasan-gce-root
2019/11/13 21:43 https://android.googlesource.com/kernel/common android-4.9 7fe05eede1c8 048f2d49 .config console log report ci-android-49-kasan-gce-root
2019/11/11 12:33 https://android.googlesource.com/kernel/common android-4.9 7fe05eede1c8 dc438b91 .config console log report ci-android-49-kasan-gce-root
2019/11/03 18:14 https://android.googlesource.com/kernel/common android-4.9 7fe05eede1c8 c9610487 .config console log report ci-android-49-kasan-gce-root
2019/11/03 14:08 https://android.googlesource.com/kernel/common android-4.9 7fe05eede1c8 c9610487 .config console log report ci-android-49-kasan-gce-root
2019/11/01 16:31 https://android.googlesource.com/kernel/common android-4.9 7fe05eede1c8 a41ca8fa .config console log report ci-android-49-kasan-gce-root
2019/10/31 20:21 https://android.googlesource.com/kernel/common android-4.9 7fe05eede1c8 a41ca8fa .config console log report ci-android-49-kasan-gce-root
2019/10/29 17:22 https://android.googlesource.com/kernel/common android-4.9 7fe05eede1c8 5ea87a66 .config console log report ci-android-49-kasan-gce-root
2019/10/29 01:45 https://android.googlesource.com/kernel/common android-4.9 7fe05eede1c8 439d7b14 .config console log report ci-android-49-kasan-gce-root
2019/10/26 14:06 https://android.googlesource.com/kernel/common android-4.9 7fe05eede1c8 413926c5 .config console log report ci-android-49-kasan-gce-root
2019/10/22 22:48 https://android.googlesource.com/kernel/common android-4.9 7fe05eede1c8 5681358a .config console log report ci-android-49-kasan-gce-root
2019/10/21 11:26 https://android.googlesource.com/kernel/common android-4.9 7fe05eede1c8 8c88c9c1 .config console log report ci-android-49-kasan-gce-root
2019/10/20 11:37 https://android.googlesource.com/kernel/common android-4.9 7fe05eede1c8 8c88c9c1 .config console log report ci-android-49-kasan-gce-root
2019/10/19 13:18 https://android.googlesource.com/kernel/common android-4.9 7fe05eede1c8 8c88c9c1 .config console log report ci-android-49-kasan-gce-root
2019/10/19 11:30 https://android.googlesource.com/kernel/common android-4.9 7fe05eede1c8 8c88c9c1 .config console log report ci-android-49-kasan-gce-root
2019/10/19 08:03 https://android.googlesource.com/kernel/common android-4.9 7fe05eede1c8 8c88c9c1 .config console log report ci-android-49-kasan-gce-root
2019/10/12 09:27 https://android.googlesource.com/kernel/common android-4.9 7fe05eede1c8 426631dd .config console log report ci-android-49-kasan-gce-root
2019/10/06 17:01 https://android.googlesource.com/kernel/common android-4.9 7fe05eede1c8 f3f7d9c8 .config console log report ci-android-49-kasan-gce-root
2019/10/01 14:48 https://android.googlesource.com/kernel/common android-4.9 7fe05eede1c8 b7a87a83 .config console log report ci-android-49-kasan-gce-root
2019/10/01 13:39 https://android.googlesource.com/kernel/common android-4.9 7fe05eede1c8 b7a87a83 .config console log report ci-android-49-kasan-gce-root
2019/09/30 04:15 https://android.googlesource.com/kernel/common android-4.9 7fe05eede1c8 c1ad5441 .config console log report ci-android-49-kasan-gce-root
2019/09/29 10:20 https://android.googlesource.com/kernel/common android-4.9 7fe05eede1c8 c1ad5441 .config console log report ci-android-49-kasan-gce-root
2019/09/27 11:21 https://android.googlesource.com/kernel/common android-4.9 7fe05eede1c8 2f1548bc .config console log report ci-android-49-kasan-gce-root
2019/09/26 17:54 https://android.googlesource.com/kernel/common android-4.9 8fe428403e30 24d405a3 .config console log report ci-android-49-kasan-gce
2019/09/21 19:12 https://android.googlesource.com/kernel/common android-4.9 8fe428403e30 d96e88f3 .config console log report ci-android-49-kasan-gce
2019/09/18 05:40 https://android.googlesource.com/kernel/common android-4.9 8fe428403e30 03e0d245 .config console log report ci-android-49-kasan-gce
2019/09/08 06:10 https://android.googlesource.com/kernel/common android-4.9 8fe428403e30 a60cb4cd .config console log report ci-android-49-kasan-gce
2019/09/03 16:18 https://android.googlesource.com/kernel/common android-4.9 8fe428403e30 48448e71 .config console log report ci-android-49-kasan-gce
2019/09/01 23:55 https://android.googlesource.com/kernel/common android-4.9 1488597c127f bad3cce2 .config console log report ci-android-49-kasan-gce-root
2019/08/21 00:26 https://android.googlesource.com/kernel/common android-4.9 9e50cb052183 cfc9868f .config console log report ci-android-49-kasan-gce-root
2019/08/19 05:10 https://android.googlesource.com/kernel/common android-4.9 10c44c01f78e b8ceabfc .config console log report ci-android-49-kasan-gce-root
2019/08/16 07:08 https://android.googlesource.com/kernel/common android-4.9 d1f8a9bb810e 8fd428a1 .config console log report ci-android-49-kasan-gce-root
2019/08/02 18:08 https://android.googlesource.com/kernel/common android-4.9 8ed00839a550 835dffe7 .config console log report ci-android-49-kasan-gce-root
2019/07/27 14:18 https://android.googlesource.com/kernel/common android-4.9 3244efed0310 c85e1c5b .config console log report ci-android-49-kasan-gce-root
2019/07/18 23:15 https://android.googlesource.com/kernel/common android-4.9 5e2c340821b1 7bb222f7 .config console log report ci-android-49-kasan-gce-root
2019/06/28 09:13 https://android.googlesource.com/kernel/common android-4.9 a80a7ab5f7c3 7509bf36 .config console log report ci-android-49-kasan-gce-root
2019/06/24 18:06 https://android.googlesource.com/kernel/common android-4.9 4395469838e0 472f0082 .config console log report ci-android-49-kasan-gce-root
2019/06/24 11:13 https://android.googlesource.com/kernel/common android-4.9 4395469838e0 472f0082 .config console log report ci-android-49-kasan-gce-root
2019/11/07 20:19 https://android.googlesource.com/kernel/common android-4.9 8fe428403e30 f39aff9e .config console log report ci-android-49-kasan-gce-386
2019/10/22 13:59 https://android.googlesource.com/kernel/common android-4.9 8fe428403e30 c59a7cd8 .config console log report ci-android-49-kasan-gce-386
2019/09/13 15:38 https://android.googlesource.com/kernel/common android-4.9 8fe428403e30 40fa42bc .config console log report ci-android-49-kasan-gce-386
* Struck through repros no longer work on HEAD.