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INFO: task hung in blkdev_reread_part

Status: public: reported C repro on 2019/04/10 16:04
Reported-by: syzbot+b779ba2bf386464eebd0@syzkaller.appspotmail.com
First crash: 2274d, last: 1824d
▶ ▼ Similar bugs (4)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-49 INFO: task hung in blkdev_reread_part syz 380 1831d 2050d 0/3 public: reported syz repro on 2019/04/14 09:28
linux-4.14 INFO: task hung in blkdev_reread_part C error 40 799d 2053d 0/1 upstream: reported C repro on 2019/04/11 11:39
android-44 INFO: task hung in blkdev_reread_part syz 25 1847d 2051d 0/2 public: reported syz repro on 2019/04/14 00:02
upstream INFO: task hung in blkdev_reread_part block 4 2430d 2541d 0/28 closed as dup on 2017/12/12 16:29

Sample crash report:
INFO: task syz-executor825:1893 blocked for more than 140 seconds.
      Not tainted 4.14.88+ #23
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor825 D27408  1893   1883 0x00000004
Call Trace:
 schedule+0x7f/0x1b0 kernel/sched/core.c:3490
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3548
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x521/0x1480 kernel/locking/mutex.c:893
 blkdev_reread_part+0x18/0x30 block/ioctl.c:192
 loop_reread_partitions+0x72/0x80 drivers/block/loop.c:614
 loop_set_status+0xa84/0xf40 drivers/block/loop.c:1169
 loop_set_status64+0x8d/0xe0 drivers/block/loop.c:1287
 lo_ioctl+0x3cd/0x17d0 drivers/block/loop.c:1400
 __blkdev_driver_ioctl block/ioctl.c:297 [inline]
 blkdev_ioctl+0x57d/0x18c0 block/ioctl.c:594
 block_ioctl+0xd9/0x120 fs/block_dev.c:1873
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0x1a0/0x1030 fs/ioctl.c:684
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x7e/0xb0 fs/ioctl.c:692
 do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x441247
RSP: 002b:00007ffc0bb3bbf8 EFLAGS: 00000202 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000441247
RDX: 00007ffc0bb3bc90 RSI: 0000000000004c04 RDI: 0000000000000005
RBP: 0000000000000010 R08: 0000000000000000 R09: 000000000000000a
R10: 0000000000000075 R11: 0000000000000202 R12: 0000000000000005
R13: 0000000000000004 R14: 0000000000000004 R15: 0000000000000000
INFO: task syz-executor825:1898 blocked for more than 140 seconds.
      Not tainted 4.14.88+ #23
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor825 D28184  1898   1884 0x00000004
Call Trace:
 schedule+0x7f/0x1b0 kernel/sched/core.c:3490
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3548
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x521/0x1480 kernel/locking/mutex.c:893
 blkdev_reread_part+0x18/0x30 block/ioctl.c:192
 loop_reread_partitions+0x72/0x80 drivers/block/loop.c:614
 loop_set_status+0xa84/0xf40 drivers/block/loop.c:1169
 loop_set_status64+0x8d/0xe0 drivers/block/loop.c:1287
 lo_ioctl+0x3cd/0x17d0 drivers/block/loop.c:1400
 __blkdev_driver_ioctl block/ioctl.c:297 [inline]
 blkdev_ioctl+0x57d/0x18c0 block/ioctl.c:594
 block_ioctl+0xd9/0x120 fs/block_dev.c:1873
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0x1a0/0x1030 fs/ioctl.c:684
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x7e/0xb0 fs/ioctl.c:692
 do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x441247
RSP: 002b:00007ffc0bb3bbf8 EFLAGS: 00000202 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000441247
RDX: 00007ffc0bb3bc90 RSI: 0000000000004c04 RDI: 0000000000000005
RBP: 0000000000000010 R08: 0000000000000000 R09: 000000000000000a
R10: 0000000000000075 R11: 0000000000000202 R12: 0000000000000005
R13: 0000000000000004 R14: 0000000000000004 R15: 0000000000000000
INFO: task syz-executor825:1903 blocked for more than 140 seconds.
      Not tainted 4.14.88+ #23
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor825 D28360  1903   1882 0x00000004
Call Trace:
 schedule+0x7f/0x1b0 kernel/sched/core.c:3490
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3548
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x521/0x1480 kernel/locking/mutex.c:893
 blkdev_reread_part+0x18/0x30 block/ioctl.c:192
 loop_reread_partitions+0x72/0x80 drivers/block/loop.c:614
 loop_set_status+0xa84/0xf40 drivers/block/loop.c:1169
 loop_set_status64+0x8d/0xe0 drivers/block/loop.c:1287
 lo_ioctl+0x3cd/0x17d0 drivers/block/loop.c:1400
 __blkdev_driver_ioctl block/ioctl.c:297 [inline]
 blkdev_ioctl+0x57d/0x18c0 block/ioctl.c:594
 block_ioctl+0xd9/0x120 fs/block_dev.c:1873
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0x1a0/0x1030 fs/ioctl.c:684
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x7e/0xb0 fs/ioctl.c:692
 do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x441247
RSP: 002b:00007ffc0bb3bbf8 EFLAGS: 00000202 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000441247
RDX: 00007ffc0bb3bc90 RSI: 0000000000004c04 RDI: 0000000000000005
RBP: 0000000000000010 R08: 0000000000000000 R09: 000000000000000a
R10: 0000000000000075 R11: 0000000000000202 R12: 0000000000000005
R13: 0000000000000004 R14: 0000000000000004 R15: 0000000000000000
INFO: task blkid:1909 blocked for more than 140 seconds.
      Not tainted 4.14.88+ #23
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
blkid           D28008  1909   1896 0x00000004
Call Trace:
 schedule+0x7f/0x1b0 kernel/sched/core.c:3490
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3548
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x521/0x1480 kernel/locking/mutex.c:893
 lo_release+0x1a/0x190 drivers/block/loop.c:1635
 __blkdev_put+0x526/0x6e0 fs/block_dev.c:1783
 blkdev_close+0x86/0xb0 fs/block_dev.c:1855
 __fput+0x25e/0x6f0 fs/file_table.c:210
 task_work_run+0x116/0x190 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:191 [inline]
 exit_to_usermode_loop+0x12e/0x150 arch/x86/entry/common.c:163
 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:267 [inline]
 do_syscall_64+0x35d/0x4b0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x7f6394d8a2b0
RSP: 002b:00007fff754db3d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007f6394d8a2b0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000028 R09: 0000000001680000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000016c2030
R13: 0000000000000000 R14: 0000000000000003 R15: 0000000000000005
INFO: task syz-executor825:1914 blocked for more than 140 seconds.
      Not tainted 4.14.88+ #23
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor825 D29656  1914   1885 0x00000004
Call Trace:
 schedule+0x7f/0x1b0 kernel/sched/core.c:3490
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3548
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x521/0x1480 kernel/locking/mutex.c:893
 loop_control_ioctl+0x71/0x310 drivers/block/loop.c:1951
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0x1a0/0x1030 fs/ioctl.c:684
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x7e/0xb0 fs/ioctl.c:692
 do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x441339
RSP: 002b:00007ffc0bb3be38 EFLAGS: 00000213 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000441339
RDX: 0000000000000000 RSI: 0000000000004c81 RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000001
R10: 000000000153e880 R11: 0000000000000213 R12: 00000000000b3358
R13: 0000000000402200 R14: 0000000000000000 R15: 0000000000000000
INFO: task syz-executor825:1915 blocked for more than 140 seconds.
      Not tainted 4.14.88+ #23
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor825 D29656  1915   1887 0x00000004
Call Trace:
 schedule+0x7f/0x1b0 kernel/sched/core.c:3490
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3548
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x521/0x1480 kernel/locking/mutex.c:893
 loop_control_ioctl+0x71/0x310 drivers/block/loop.c:1951
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0x1a0/0x1030 fs/ioctl.c:684
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x7e/0xb0 fs/ioctl.c:692
 do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x441339
RSP: 002b:00007ffc0bb3be38 EFLAGS: 00000213 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000441339
RDX: 0000000000000000 RSI: 0000000000004c81 RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000001
R10: 000000000153e880 R11: 0000000000000213 R12: 00000000000b3355
R13: 0000000000402200 R14: 0000000000000000 R15: 0000000000000000
INFO: task syz-executor825:1916 blocked for more than 140 seconds.
      Not tainted 4.14.88+ #23
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor825 D29656  1916   1886 0x00000004
Call Trace:
 schedule+0x7f/0x1b0 kernel/sched/core.c:3490
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3548
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x521/0x1480 kernel/locking/mutex.c:893
 loop_control_ioctl+0x180/0x310 drivers/block/loop.c:1965
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0x1a0/0x1030 fs/ioctl.c:684
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x7e/0xb0 fs/ioctl.c:692
 do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x441339
RSP: 002b:00007ffc0bb3be38 EFLAGS: 00000213 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000441339
RDX: 0000000000000000 RSI: 0000000000004c81 RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000001
R10: 000000000153e880 R11: 0000000000000213 R12: 00000000000b33da
R13: 0000000000402200 R14: 0000000000000000 R15: 0000000000000000
INFO: task blkid:1917 blocked for more than 140 seconds.
      Not tainted 4.14.88+ #23
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
blkid           D27816  1917   1895 0x00000004
Call Trace:
 schedule+0x7f/0x1b0 kernel/sched/core.c:3490
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3548
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x521/0x1480 kernel/locking/mutex.c:893
 lo_open+0x17/0xa0 drivers/block/loop.c:1592
 __blkdev_get+0x8e2/0xe50 fs/block_dev.c:1529
 blkdev_get+0x97/0x8c0 fs/block_dev.c:1604
 blkdev_open+0x1bd/0x240 fs/block_dev.c:1762
 do_dentry_open+0x426/0xda0 fs/open.c:764
 vfs_open+0x11c/0x210 fs/open.c:878
 do_last fs/namei.c:3455 [inline]
 path_openat+0x5f9/0x2930 fs/namei.c:3597
 do_filp_open+0x197/0x270 fs/namei.c:3631
 do_sys_open+0x2ef/0x580 fs/open.c:1071
 do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x7f5aa593d120
RSP: 002b:00007ffe28d6a108 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f5aa593d120
RDX: 00007ffe28d6af41 RSI: 0000000000000000 RDI: 00007ffe28d6af41
RBP: 0000000000000000 R08: 0000000000000078 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000181c030
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000005
INFO: task blkid:1918 blocked for more than 140 seconds.
      Not tainted 4.14.88+ #23
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
blkid           D29000  1918   1899 0x00000004
Call Trace:
 schedule+0x7f/0x1b0 kernel/sched/core.c:3490
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3548
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x521/0x1480 kernel/locking/mutex.c:893
 lo_open+0x17/0xa0 drivers/block/loop.c:1592
 __blkdev_get+0x8e2/0xe50 fs/block_dev.c:1529
 blkdev_get+0x97/0x8c0 fs/block_dev.c:1604
 blkdev_open+0x1bd/0x240 fs/block_dev.c:1762
 do_dentry_open+0x426/0xda0 fs/open.c:764
 vfs_open+0x11c/0x210 fs/open.c:878
 do_last fs/namei.c:3455 [inline]
 path_openat+0x5f9/0x2930 fs/namei.c:3597
 do_filp_open+0x197/0x270 fs/namei.c:3631
 do_sys_open+0x2ef/0x580 fs/open.c:1071
 do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x7fcec469a120
RSP: 002b:00007ffddf120668 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fcec469a120
RDX: 00007ffddf121f41 RSI: 0000000000000000 RDI: 00007ffddf121f41
RBP: 0000000000000000 R08: 0000000000000078 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000023f0030
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000005
INFO: task blkid:1919 blocked for more than 140 seconds.
      Not tainted 4.14.88+ #23
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
blkid           D27816  1919   1892 0x00000004
Call Trace:
 schedule+0x7f/0x1b0 kernel/sched/core.c:3490
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3548
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x521/0x1480 kernel/locking/mutex.c:893
 lo_open+0x17/0xa0 drivers/block/loop.c:1592
 __blkdev_get+0x267/0xe50 fs/block_dev.c:1467
 blkdev_get+0x97/0x8c0 fs/block_dev.c:1604
 blkdev_open+0x1bd/0x240 fs/block_dev.c:1762
 do_dentry_open+0x426/0xda0 fs/open.c:764
 vfs_open+0x11c/0x210 fs/open.c:878
 do_last fs/namei.c:3455 [inline]
 path_openat+0x5f9/0x2930 fs/namei.c:3597
 do_filp_open+0x197/0x270 fs/namei.c:3631
 do_sys_open+0x2ef/0x580 fs/open.c:1071
 do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x7f558d692120
RSP: 002b:00007ffddd4e7b08 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f558d692120
RDX: 00007ffddd4e9f41 RSI: 0000000000000000 RDI: 00007ffddd4e9f41
RBP: 0000000000000000 R08: 0000000000000078 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000b78030
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000005

Showing all locks held in the system:
1 lock held by khungtaskd/23:
 #0:  (tasklist_lock){.+.+}, at: [<ffffffffa2e04947>] debug_show_all_locks+0x74/0x20f kernel/locking/lockdep.c:4541
1 lock held by rsyslogd/1624:
 #0:  (&f->f_pos_lock){+.+.}, at: [<ffffffffa31c0e92>] __fdget_pos+0xa2/0xc0 fs/file.c:768
2 locks held by getty/1752:
 #0:  (&tty->ldisc_sem){++++}, at: [<ffffffffa3940870>] tty_ldisc_ref_wait+0x20/0x80 drivers/tty/tty_ldisc.c:275
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<ffffffffa393bccf>] n_tty_read+0x1ff/0x1700 drivers/tty/n_tty.c:2156
2 locks held by syz-executor825/1893:
 #0:  (&lo->lo_ctl_mutex/1){+.+.}, at: [<ffffffffa39eff95>] lo_ioctl+0x85/0x17d0 drivers/block/loop.c:1373
 #1:  (&bdev->bd_mutex){+.+.}, at: [<ffffffffa37215a8>] blkdev_reread_part+0x18/0x30 block/ioctl.c:192
2 locks held by syz-executor825/1898:
 #0:  (&lo->lo_ctl_mutex/1){+.+.}, at: [<ffffffffa39eff95>] lo_ioctl+0x85/0x17d0 drivers/block/loop.c:1373
 #1:  (&bdev->bd_mutex){+.+.}, at: [<ffffffffa37215a8>] blkdev_reread_part+0x18/0x30 block/ioctl.c:192
2 locks held by syz-executor825/1903:
 #0:  (&lo->lo_ctl_mutex/1){+.+.}, at: [<ffffffffa39eff95>] lo_ioctl+0x85/0x17d0 drivers/block/loop.c:1373
 #1:  (&bdev->bd_mutex){+.+.}, at: [<ffffffffa37215a8>] blkdev_reread_part+0x18/0x30 block/ioctl.c:192
2 locks held by blkid/1909:
 #0:  (&bdev->bd_mutex){+.+.}, at: [<ffffffffa321c681>] __blkdev_put+0xb1/0x6e0 fs/block_dev.c:1770
 #1:  (loop_index_mutex){+.+.}, at: [<ffffffffa39f182a>] lo_release+0x1a/0x190 drivers/block/loop.c:1635
1 lock held by syz-executor825/1914:
 #0:  (loop_index_mutex){+.+.}, at: [<ffffffffa39f2d01>] loop_control_ioctl+0x71/0x310 drivers/block/loop.c:1951
1 lock held by syz-executor825/1915:
 #0:  (loop_index_mutex){+.+.}, at: [<ffffffffa39f2d01>] loop_control_ioctl+0x71/0x310 drivers/block/loop.c:1951
2 locks held by syz-executor825/1916:
 #0:  (loop_index_mutex){+.+.}, at: [<ffffffffa39f2d01>] loop_control_ioctl+0x71/0x310 drivers/block/loop.c:1951
 #1:  (&lo->lo_ctl_mutex#2){+.+.}, at: [<ffffffffa39f2e10>] loop_control_ioctl+0x180/0x310 drivers/block/loop.c:1965
2 locks held by blkid/1917:
 #0:  (&bdev->bd_mutex){+.+.}, at: [<ffffffffa321cda3>] __blkdev_get+0xf3/0xe50 fs/block_dev.c:1452
 #1:  (loop_index_mutex){+.+.}, at: [<ffffffffa39eb7c7>] lo_open+0x17/0xa0 drivers/block/loop.c:1592
2 locks held by blkid/1918:
 #0:  (&bdev->bd_mutex){+.+.}, at: [<ffffffffa321cda3>] __blkdev_get+0xf3/0xe50 fs/block_dev.c:1452
 #1:  (loop_index_mutex){+.+.}, at: [<ffffffffa39eb7c7>] lo_open+0x17/0xa0 drivers/block/loop.c:1592
2 locks held by blkid/1919:
 #0:  (&bdev->bd_mutex){+.+.}, at: [<ffffffffa321cda3>] __blkdev_get+0xf3/0xe50 fs/block_dev.c:1452
 #1:  (loop_index_mutex){+.+.}, at: [<ffffffffa39eb7c7>] lo_open+0x17/0xa0 drivers/block/loop.c:1592
2 locks held by blkid/1920:
 #0:  (&bdev->bd_mutex){+.+.}, at: [<ffffffffa321cda3>] __blkdev_get+0xf3/0xe50 fs/block_dev.c:1452
 #1:  (loop_index_mutex){+.+.}, at: [<ffffffffa39eb7c7>] lo_open+0x17/0xa0 drivers/block/loop.c:1592
2 locks held by blkid/1922:
 #0:  (&bdev->bd_mutex){+.+.}, at: [<ffffffffa321cda3>] __blkdev_get+0xf3/0xe50 fs/block_dev.c:1452
 #1:  (loop_index_mutex){+.+.}, at: [<ffffffffa39eb7c7>] lo_open+0x17/0xa0 drivers/block/loop.c:1592

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

NMI backtrace for cpu 1
CPU: 1 PID: 23 Comm: khungtaskd Not tainted 4.14.88+ #23
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0xb9/0x11b lib/dump_stack.c:53
 nmi_cpu_backtrace.cold.0+0x47/0x85 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x121/0x146 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:140 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:196 [inline]
 watchdog+0x574/0xa70 kernel/hung_task.c:252
 kthread+0x348/0x420 kernel/kthread.c:232
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:402
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.14.88+ #23
task: ffffffffa5031200 task.stack: ffffffffa5000000
RIP: 0010:__local_bh_disable_ip+0x0/0xc0 kernel/softirq.c:111
RSP: 0018:ffff8881dba07fb0 EFLAGS: 00000046
RAX: 0000000080000001 RBX: ffffffffa5031200 RCX: 1ffffffff49d5884
RDX: 0000000000000000 RSI: 0000000000000200 RDI: ffffffffa2cec5ea
RBP: ffff8881dba07fe8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 000000000002a200
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8881dba00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000108a3e0 CR3: 0000000169226003 CR4: 00000000001606b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 local_bh_disable include/linux/bottom_half.h:19 [inline]
 irq_enter+0xab/0xd0 kernel/softirq.c:348
 scheduler_ipi+0xb6/0x340 kernel/sched/core.c:1812
 reschedule_interrupt+0x84/0x90 arch/x86/entry/entry_64.S:811
 </IRQ>
RIP: 0010:native_safe_halt+0x2/0x10 arch/x86/include/asm/irqflags.h:58
RSP: 0018:ffffffffa5007d28 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff02
RAX: 0000000000000007 RBX: ffffffffa542f968 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffffffffa5031a2c
RBP: ffffffffa5439da8 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 1ffffffff4a00fae R14: 0000000000000000 R15: ffffffffa5439e64
 arch_safe_halt arch/x86/include/asm/paravirt.h:94 [inline]
 default_idle+0x50/0x380 arch/x86/kernel/process.c:564
 cpuidle_idle_call kernel/sched/idle.c:159 [inline]
 do_idle+0x2da/0x3b0 kernel/sched/idle.c:268
 cpu_startup_entry+0xc9/0xe0 kernel/sched/idle.c:374
 start_kernel+0x701/0x73f init/main.c:710
 secondary_startup_64+0xa5/0xb0 arch/x86/kernel/head_64.S:240
Code: 89 04 24 e8 f3 29 44 00 48 8b 04 24 eb bd 48 89 14 24 e8 f4 29 44 00 48 8b 14 24 e9 1a ff ff ff 90 66 2e 0f 1f 84 00 00 00 00 00 <55> 53 89 f3 65 8b 05 a5 1f 33 5d a9 00 00 0f 00 0f 85 98 00 00

Crashes (538):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/12/16 00:05 android-4.14 4ee7197c44f6 def91db3 .config console log report syz C ci-android-414-kasan-gce-root
2018/10/22 05:05 android-4.14 c556d1ffe528 ecb386fe .config console log report syz C ci-android-414-kasan-gce-root
2019/03/10 08:43 android-4.14 b11964adfe4c 12365b99 .config console log report syz ci-android-414-kasan-gce-root
2019/03/07 19:14 android-4.14 a895cea2010e 8c085c5e .config console log report syz ci-android-414-kasan-gce-root
2019/11/26 15:32 android-4.14 f9b4ab5c8e99 f746151a .config console log report ci-android-414-kasan-gce-root
2019/11/18 07:51 android-4.14 460dc7c31cef d5696d51 .config console log report ci-android-414-kasan-gce-root
2019/11/16 06:46 android-4.14 460dc7c31cef cdac920b .config console log report ci-android-414-kasan-gce-root
2019/11/14 19:14 android-4.14 babe48d2e987 5d15a967 .config console log report ci-android-414-kasan-gce-root
2019/11/11 05:49 android-4.14 10e570bfc15a dc438b91 .config console log report ci-android-414-kasan-gce-root
2019/10/28 05:13 android-4.14 0b383e2946f5 25bb509e .config console log report ci-android-414-kasan-gce-root
2019/10/27 17:18 android-4.14 0b383e2946f5 25bb509e .config console log report ci-android-414-kasan-gce-root
2019/10/26 20:08 android-4.14 2d0e4c21fcee 25bb509e .config console log report ci-android-414-kasan-gce-root
2019/10/21 05:49 android-4.14 234de92896af 8c88c9c1 .config console log report ci-android-414-kasan-gce-root
2019/10/20 13:03 android-4.14 234de92896af 8c88c9c1 .config console log report ci-android-414-kasan-gce-root
2019/10/15 18:29 android-4.14 248a268ad139 b5268b89 .config console log report ci-android-414-kasan-gce-root
2019/10/03 02:30 android-4.14 80b0c73216f5 2e29b534 .config console log report ci-android-414-kasan-gce-root
2019/09/29 19:26 android-4.14 d649ef04c3ed c1ad5441 .config console log report ci-android-414-kasan-gce-root
2019/09/28 07:50 android-4.14 d649ef04c3ed d8074e0b .config console log report ci-android-414-kasan-gce-root
2019/09/25 12:59 android-4.14 8ae37de3fa03 e38a6630 .config console log report ci-android-414-kasan-gce-root
2019/09/09 14:18 android-4.14 4eccd8013349 a60cb4cd .config console log report ci-android-414-kasan-gce-root
2019/09/01 22:58 android-4.14 a9d0871a562e bad3cce2 .config console log report ci-android-414-kasan-gce-root
2019/08/13 18:59 android-4.14 0e28694fe668 ef801a3e .config console log report ci-android-414-kasan-gce-root
2019/08/04 04:03 android-4.14 2ea8815046b7 6affd8e8 .config console log report ci-android-414-kasan-gce-root
2019/07/22 18:21 android-4.14 fae940268dce b3c615f5 .config console log report ci-android-414-kasan-gce-root
2019/07/21 07:03 android-4.14 269f182fac0b 1656845f .config console log report ci-android-414-kasan-gce-root
2019/07/01 01:42 android-4.14 71162e6530df 699d6448 .config console log report ci-android-414-kasan-gce-root
2019/06/19 08:26 android-4.14 940b0b117c66 34bf9440 .config console log report ci-android-414-kasan-gce-root
2019/06/09 01:32 android-4.14 76896566d7b9 0159583c .config console log report ci-android-414-kasan-gce-root
2019/06/08 13:58 android-4.14 76896566d7b9 0159583c .config console log report ci-android-414-kasan-gce-root
2019/06/08 09:48 android-4.14 76896566d7b9 cf9c3a50 .config console log report ci-android-414-kasan-gce-root
2019/06/07 21:03 android-4.14 76896566d7b9 ce9107d0 .config console log report ci-android-414-kasan-gce-root
2019/05/02 05:24 android-4.14 c680586c4fb7 7516d9fa .config console log report ci-android-414-kasan-gce-root
2019/05/01 10:15 android-4.14 c680586c4fb7 618456b4 .config console log report ci-android-414-kasan-gce-root
2019/04/30 18:49 android-4.14 c680586c4fb7 618456b4 .config console log report ci-android-414-kasan-gce-root
2019/04/30 01:29 android-4.14 ffa22221c473 b617407b .config console log report ci-android-414-kasan-gce-root
2019/04/30 00:09 android-4.14 ffa22221c473 b617407b .config console log report ci-android-414-kasan-gce-root
2019/04/29 08:06 android-4.14 ffa22221c473 b617407b .config console log report ci-android-414-kasan-gce-root
2019/04/29 06:01 android-4.14 ffa22221c473 b617407b .config console log report ci-android-414-kasan-gce-root
2019/04/28 17:18 android-4.14 ffa22221c473 b617407b .config console log report ci-android-414-kasan-gce-root
2019/04/26 16:26 android-4.14 ffa22221c473 b617407b .config console log report ci-android-414-kasan-gce-root
2019/04/26 11:18 android-4.14 ffa22221c473 b617407b .config console log report ci-android-414-kasan-gce-root
2019/04/26 02:24 android-4.14 ffa22221c473 f46aabc8 .config console log report ci-android-414-kasan-gce-root
2019/04/25 22:43 android-4.14 ffa22221c473 f46aabc8 .config console log report ci-android-414-kasan-gce-root
2019/04/25 19:41 android-4.14 ffa22221c473 f46aabc8 .config console log report ci-android-414-kasan-gce-root
2019/04/24 21:24 android-4.14 ffa22221c473 8e3c52b1 .config console log report ci-android-414-kasan-gce-root
2019/04/24 18:55 android-4.14 ffa22221c473 8e3c52b1 .config console log report ci-android-414-kasan-gce-root
2019/04/24 07:11 android-4.14 ffa22221c473 4d3d6a50 .config console log report ci-android-414-kasan-gce-root
2019/04/23 16:49 android-4.14 fde41616bce4 53199d6e .config console log report ci-android-414-kasan-gce-root
2019/04/23 06:23 android-4.14 fde41616bce4 53199d6e .config console log report ci-android-414-kasan-gce-root
2019/04/22 22:56 android-4.14 fde41616bce4 53199d6e .config console log report ci-android-414-kasan-gce-root
2019/04/22 15:09 android-4.14 fde41616bce4 0a77c33c .config console log report ci-android-414-kasan-gce-root
2019/04/22 04:17 android-4.14 fde41616bce4 b0e8efcb .config console log report ci-android-414-kasan-gce-root
2018/09/02 19:01 android-4.14 47350a9f13c6 a4718693 .config console log report ci-android-414-kasan-gce-root
* Struck through repros no longer work on HEAD.