syzbot


INFO: task hung in lo_release
Status: fixed on 2019/12/17 00:29
Reported-by: syzbot+9cd7e6cc5a771088b5a4@syzkaller.appspotmail.com
Fix commit: 22f36db48781 Revert "block/loop: Use global lock for ioctl() operation."
First crash: 1139d, last: 1026d

Fix bisection: fixed by (bisect log) :
commit 22f36db48781d0db6a01ee0113265984990c1a8e
Author: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Date: Mon Apr 29 13:56:26 2019 +0000

  Revert "block/loop: Use global lock for ioctl() operation."

similar bugs (7):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in lo_release 1 1406d 1406d 12/22 fixed on 2019/01/15 20:25
android-49 INFO: task hung in lo_release 867 1041d 1136d 0/3 auto-closed as invalid on 2019/10/25 14:11
linux-4.14 INFO: task hung in lo_release (2) C 16 1h18m 796d 0/1 upstream: reported C repro on 2020/03/19 00:28
upstream INFO: task hung in lo_release (2) 38 183d 183d 0/22 closed as dup on 2021/11/23 00:29
android-49 INFO: task hung in lo_release (2) 3 919d 931d 0/3 auto-closed as invalid on 2020/03/16 04:39
android-414 INFO: task hung in lo_release syz 1670 913d 1138d 0/1 public: reported syz repro on 2019/04/12 00:01
android-44 INFO: task hung in lo_release syz 59 907d 1136d 0/2 public: reported syz repro on 2019/04/14 00:02

Sample crash report:
IPv6: ADDRCONF(NETDEV_CHANGE): hsr0: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): veth1_to_hsr: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): hsr_slave_1: link becomes ready
IPv6: ADDRCONF(NETDEV_UP): vxcan1: link is not ready
8021q: adding VLAN 0 to HW filter on device batadv0
INFO: task syz-executor.5:7014 blocked for more than 140 seconds.
      Not tainted 4.14.114 #4
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.5  D24992  7014      1 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2807 [inline]
 __schedule+0x7be/0x1cf0 kernel/sched/core.c:3383
 schedule+0x92/0x1c0 kernel/sched/core.c:3427
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3485
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x73c/0x1470 kernel/locking/mutex.c:893
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908
 __lo_release drivers/block/loop.c:1644 [inline]
 lo_release+0x84/0x1b0 drivers/block/loop.c:1668
 __blkdev_put+0x436/0x7f0 fs/block_dev.c:1791
 blkdev_put+0x88/0x510 fs/block_dev.c:1856
 blkdev_close+0x8b/0xb0 fs/block_dev.c:1863
 __fput+0x277/0x7a0 fs/file_table.c:210
 ____fput+0x16/0x20 fs/file_table.c:244
 task_work_run+0x119/0x190 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:191 [inline]
 exit_to_usermode_loop+0x1da/0x220 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+0x4a9/0x630 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x412b40
RSP: 002b:00007ffc417a6aa8 EFLAGS: 00000246 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000003 RCX: 0000000000412b40
RDX: 0000000000000000 RSI: 0000000000004c01 RDI: 0000000000000003
RBP: 0000000000000003 R08: 0000000000000000 R09: 000000000000000a
R10: 0000000000000075 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffc417a6ae0 R14: 00000000000f2464 R15: 00007ffc417a6af0
INFO: task syz-executor.1:7163 blocked for more than 140 seconds.
      Not tainted 4.14.114 #4
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.1  D28176  7163   7007 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2807 [inline]
 __schedule+0x7be/0x1cf0 kernel/sched/core.c:3383
 schedule+0x92/0x1c0 kernel/sched/core.c:3427
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3485
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x73c/0x1470 kernel/locking/mutex.c:893
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908
 lo_ioctl+0x87/0x1c70 drivers/block/loop.c:1405
 __blkdev_driver_ioctl block/ioctl.c:297 [inline]
 blkdev_ioctl+0x983/0x1880 block/ioctl.c:594
 block_ioctl+0xde/0x120 fs/block_dev.c:1881
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0x7b9/0x1070 fs/ioctl.c:684
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692
 do_syscall_64+0x1eb/0x630 arch/x86/entry/common.c:289
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x458da9
RSP: 002b:00007ffd0b4eb188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000458da9
RDX: 0000000000000004 RSI: 0000000000004c00 RDI: 0000000000000003
RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000017d0914
R13: 00000000004c2093 R14: 00000000004d4958 R15: 00000000ffffffff
INFO: task blkid:7164 blocked for more than 140 seconds.
      Not tainted 4.14.114 #4
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
blkid           D28744  7164   6968 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2807 [inline]
 __schedule+0x7be/0x1cf0 kernel/sched/core.c:3383
 schedule+0x92/0x1c0 kernel/sched/core.c:3427
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3485
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x73c/0x1470 kernel/locking/mutex.c:893
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908
 lo_ioctl+0x87/0x1c70 drivers/block/loop.c:1405
 __blkdev_driver_ioctl block/ioctl.c:297 [inline]
 blkdev_ioctl+0x983/0x1880 block/ioctl.c:594
 block_ioctl+0xde/0x120 fs/block_dev.c:1881
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0x7b9/0x1070 fs/ioctl.c:684
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692
 do_syscall_64+0x1eb/0x630 arch/x86/entry/common.c:289
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x7f53e5150347
RSP: 002b:00007ffc7c36d138 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000001d18030 RCX: 00007f53e5150347
RDX: 0000000000000000 RSI: 0000000000005331 RDI: 0000000000000003
RBP: 0000000000000003 R08: 00007f53e54005a0 R09: 0000000000000008
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000003 R15: 0000000000000005
INFO: task blkid:7165 blocked for more than 140 seconds.
      Not tainted 4.14.114 #4
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
blkid           D29040  7165   7082 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2807 [inline]
 __schedule+0x7be/0x1cf0 kernel/sched/core.c:3383
 schedule+0x92/0x1c0 kernel/sched/core.c:3427
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3485
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x73c/0x1470 kernel/locking/mutex.c:893
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908
 lo_ioctl+0x87/0x1c70 drivers/block/loop.c:1405
 __blkdev_driver_ioctl block/ioctl.c:297 [inline]
 blkdev_ioctl+0x983/0x1880 block/ioctl.c:594
 block_ioctl+0xde/0x120 fs/block_dev.c:1881
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0x7b9/0x1070 fs/ioctl.c:684
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692
 do_syscall_64+0x1eb/0x630 arch/x86/entry/common.c:289
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x7efc97507347
RSP: 002b:00007ffc5a621bf8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000001e8c030 RCX: 00007efc97507347
RDX: 0000000000000000 RSI: 0000000000005331 RDI: 0000000000000003
RBP: 0000000000000003 R08: 00007efc977b75a0 R09: 0000000000000008
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000003 R15: 0000000000000005
INFO: task syz-executor.2:7166 blocked for more than 140 seconds.
      Not tainted 4.14.114 #4
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.2  D28528  7166   7004 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2807 [inline]
 __schedule+0x7be/0x1cf0 kernel/sched/core.c:3383
 schedule+0x92/0x1c0 kernel/sched/core.c:3427
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3485
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x73c/0x1470 kernel/locking/mutex.c:893
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908
 lo_ioctl+0x87/0x1c70 drivers/block/loop.c:1405
 __blkdev_driver_ioctl block/ioctl.c:297 [inline]
 blkdev_ioctl+0x983/0x1880 block/ioctl.c:594
 block_ioctl+0xde/0x120 fs/block_dev.c:1881
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0x7b9/0x1070 fs/ioctl.c:684
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692
 do_syscall_64+0x1eb/0x630 arch/x86/entry/common.c:289
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x458da9
RSP: 002b:00007ffff11d1248 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000458da9
RDX: 0000000000000004 RSI: 0000000000004c00 RDI: 0000000000000003
RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000bf3914
R13: 00000000004c2093 R14: 00000000004d4958 R15: 00000000ffffffff
INFO: task blkid:7167 blocked for more than 140 seconds.
      Not tainted 4.14.114 #4
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
blkid           D29040  7167   6969 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2807 [inline]
 __schedule+0x7be/0x1cf0 kernel/sched/core.c:3383
 schedule+0x92/0x1c0 kernel/sched/core.c:3427
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3485
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x73c/0x1470 kernel/locking/mutex.c:893
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908
 lo_ioctl+0x87/0x1c70 drivers/block/loop.c:1405
 __blkdev_driver_ioctl block/ioctl.c:297 [inline]
 blkdev_ioctl+0x983/0x1880 block/ioctl.c:594
 block_ioctl+0xde/0x120 fs/block_dev.c:1881
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0x7b9/0x1070 fs/ioctl.c:684
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692
 do_syscall_64+0x1eb/0x630 arch/x86/entry/common.c:289
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x7fe920318347
RSP: 002b:00007fff1738d098 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00000000018b5030 RCX: 00007fe920318347
RDX: 0000000000000000 RSI: 0000000000005331 RDI: 0000000000000003
RBP: 0000000000000003 R08: 00007fe9205c85a0 R09: 0000000000000008
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000003 R15: 0000000000000005
INFO: task syz-executor.4:7168 blocked for more than 140 seconds.
      Not tainted 4.14.114 #4
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.4  D28528  7168   7013 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2807 [inline]
 __schedule+0x7be/0x1cf0 kernel/sched/core.c:3383
 schedule+0x92/0x1c0 kernel/sched/core.c:3427
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3485
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x73c/0x1470 kernel/locking/mutex.c:893
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908
 blkdev_reread_part+0x1f/0x40 block/ioctl.c:192
 loop_reread_partitions+0x7c/0x90 drivers/block/loop.c:615
 loop_set_status+0xc28/0x1200 drivers/block/loop.c:1184
 loop_set_status64+0xa6/0xf0 drivers/block/loop.c:1302
 lo_ioctl+0x5c1/0x1c70 drivers/block/loop.c:1432
 __blkdev_driver_ioctl block/ioctl.c:297 [inline]
 blkdev_ioctl+0x983/0x1880 block/ioctl.c:594
 block_ioctl+0xde/0x120 fs/block_dev.c:1881
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0x7b9/0x1070 fs/ioctl.c:684
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692
 do_syscall_64+0x1eb/0x630 arch/x86/entry/common.c:289
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x458da9
RSP: 002b:00007ffe96380418 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000458da9
RDX: 0000000020000080 RSI: 0000000000004c04 RDI: 0000000000000003
RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000a7d914
R13: 00000000004c219c R14: 00000000004d4a78 R15: 00000000ffffffff
INFO: task syz-executor.0:7169 blocked for more than 140 seconds.
      Not tainted 4.14.114 #4
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.0  D28368  7169   7009 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2807 [inline]
 __schedule+0x7be/0x1cf0 kernel/sched/core.c:3383
 schedule+0x92/0x1c0 kernel/sched/core.c:3427
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3485
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x73c/0x1470 kernel/locking/mutex.c:893
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908
 lo_open+0x1d/0xb0 drivers/block/loop.c:1624
 __blkdev_get+0xab1/0x1120 fs/block_dev.c:1537
 blkdev_get+0xa8/0x8e0 fs/block_dev.c:1612
 blkdev_open+0x1d1/0x260 fs/block_dev.c:1770
 do_dentry_open+0x73e/0xeb0 fs/open.c:758
 vfs_open+0x105/0x230 fs/open.c:872
 do_last fs/namei.c:3425 [inline]
 path_openat+0x8bd/0x3f70 fs/namei.c:3566
 do_filp_open+0x18e/0x250 fs/namei.c:3600
 do_sys_open+0x2c5/0x430 fs/open.c:1065
 SYSC_open fs/open.c:1083 [inline]
 SyS_open+0x2d/0x40 fs/open.c:1078
 do_syscall_64+0x1eb/0x630 arch/x86/entry/common.c:289
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x412d20
RSP: 002b:00007ffd02a976e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 6666666666666667 RCX: 0000000000412d20
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00007ffd02a97790
RBP: 000000000073bf00 R08: 000000000000000f R09: 0000000000000000
R10: 0000000000740090 R11: 0000000000000246 R12: 0000000000c0f914
R13: 00000000004c7b5b R14: 00000000004ddbe0 R15: 00000000ffffffff
INFO: task syz-executor.3:7174 blocked for more than 140 seconds.
      Not tainted 4.14.114 #4
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.3  D28528  7174   7011 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2807 [inline]
 __schedule+0x7be/0x1cf0 kernel/sched/core.c:3383
 schedule+0x92/0x1c0 kernel/sched/core.c:3427
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3485
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x73c/0x1470 kernel/locking/mutex.c:893
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908
 __blkdev_get+0x145/0x1120 fs/block_dev.c:1457
 blkdev_get+0xa8/0x8e0 fs/block_dev.c:1612
 blkdev_open+0x1d1/0x260 fs/block_dev.c:1770
 do_dentry_open+0x73e/0xeb0 fs/open.c:758
 vfs_open+0x105/0x230 fs/open.c:872
 do_last fs/namei.c:3425 [inline]
 path_openat+0x8bd/0x3f70 fs/namei.c:3566
 do_filp_open+0x18e/0x250 fs/namei.c:3600
 do_sys_open+0x2c5/0x430 fs/open.c:1065
 SYSC_open fs/open.c:1083 [inline]
 SyS_open+0x2d/0x40 fs/open.c:1078
 do_syscall_64+0x1eb/0x630 arch/x86/entry/common.c:289
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x412d20
RSP: 002b:00007ffffe6eef88 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 6666666666666667 RCX: 0000000000412d20
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00007ffffe6ef030
RBP: 000000000073bf00 R08: 000000000000000f R09: 0000000000000000
R10: 0000000000740090 R11: 0000000000000246 R12: 00000000016f4914
R13: 00000000004c7b5b R14: 00000000004ddbe0 R15: 00000000ffffffff
INFO: task blkid:7175 blocked for more than 140 seconds.
      Not tainted 4.14.114 #4
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
blkid           D28128  7175   7171 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2807 [inline]
 __schedule+0x7be/0x1cf0 kernel/sched/core.c:3383
 schedule+0x92/0x1c0 kernel/sched/core.c:3427
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3485
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x73c/0x1470 kernel/locking/mutex.c:893
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908
 lo_open+0x1d/0xb0 drivers/block/loop.c:1624
 __blkdev_get+0x2c9/0x1120 fs/block_dev.c:1472
 blkdev_get+0xa8/0x8e0 fs/block_dev.c:1612
 blkdev_open+0x1d1/0x260 fs/block_dev.c:1770
 do_dentry_open+0x73e/0xeb0 fs/open.c:758
 vfs_open+0x105/0x230 fs/open.c:872
 do_last fs/namei.c:3425 [inline]
 path_openat+0x8bd/0x3f70 fs/namei.c:3566
 do_filp_open+0x18e/0x250 fs/namei.c:3600
 do_sys_open+0x2c5/0x430 fs/open.c:1065
 SYSC_open fs/open.c:1083 [inline]
 SyS_open+0x2d/0x40 fs/open.c:1078
 do_syscall_64+0x1eb/0x630 arch/x86/entry/common.c:289
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x7fdf437b4120
RSP: 002b:00007ffc6afeeed8 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fdf437b4120
RDX: 00007ffc6afeff34 RSI: 0000000000000000 RDI: 00007ffc6afeff34
RBP: 0000000000000000 R08: 0000000000000078 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000017d0030
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000005

Showing all locks held in the system:
1 lock held by khungtaskd/1007:
 #0:  (tasklist_lock){.+.+}, at: [<ffffffff81487148>] debug_show_all_locks+0x7f/0x21f kernel/locking/lockdep.c:4541
1 lock held by rsyslogd/6836:
 #0:  (&f->f_pos_lock){+.+.}, at: [<ffffffff81942e9b>] __fdget_pos+0xab/0xd0 fs/file.c:769
2 locks held by getty/6959:
 #0:  (&tty->ldisc_sem){++++}, at: [<ffffffff861af743>] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:377
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff8310d3c6>] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156
2 locks held by getty/6960:
 #0:  (&tty->ldisc_sem){++++}, at: [<ffffffff861af743>] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:377
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff8310d3c6>] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156
2 locks held by getty/6961:
 #0:  (&tty->ldisc_sem){++++}, at: [<ffffffff861af743>] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:377
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff8310d3c6>] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156
2 locks held by getty/6962:
 #0:  (&tty->ldisc_sem){++++}, at: [<ffffffff861af743>] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:377
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff8310d3c6>] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156
2 locks held by getty/6963:
 #0:  (&tty->ldisc_sem){++++}, at: [<ffffffff861af743>] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:377
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff8310d3c6>] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156
2 locks held by getty/6964:
 #0:  (&tty->ldisc_sem){++++}, at: [<ffffffff861af743>] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:377
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff8310d3c6>] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156
2 locks held by getty/6965:
 #0:  (&tty->ldisc_sem){++++}, at: [<ffffffff861af743>] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:377
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff8310d3c6>] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156
3 locks held by syz-executor.5/7014:
 #0:  (&bdev->bd_mutex){+.+.}, at: [<ffffffff819a7b16>] __blkdev_put+0xa6/0x7f0 fs/block_dev.c:1778
 #1:  (loop_index_mutex){+.+.}, at: [<ffffffff8373bf4e>] lo_release+0x1e/0x1b0 drivers/block/loop.c:1667
 #2:  (loop_ctl_mutex#2){+.+.}, at: [<ffffffff8373bfb4>] __lo_release drivers/block/loop.c:1644 [inline]
 #2:  (loop_ctl_mutex#2){+.+.}, at: [<ffffffff8373bfb4>] lo_release+0x84/0x1b0 drivers/block/loop.c:1668
1 lock held by syz-executor.1/7163:
 #0:  (loop_ctl_mutex/1){+.+.}, at: [<ffffffff8373dc27>] lo_ioctl+0x87/0x1c70 drivers/block/loop.c:1405
1 lock held by blkid/7164:
 #0:  (loop_ctl_mutex/1){+.+.}, at: [<ffffffff8373dc27>] lo_ioctl+0x87/0x1c70 drivers/block/loop.c:1405
1 lock held by blkid/7165:
 #0:  (loop_ctl_mutex/1){+.+.}, at: [<ffffffff8373dc27>] lo_ioctl+0x87/0x1c70 drivers/block/loop.c:1405
1 lock held by syz-executor.2/7166:
 #0:  (loop_ctl_mutex/1){+.+.}, at: [<ffffffff8373dc27>] lo_ioctl+0x87/0x1c70 drivers/block/loop.c:1405
1 lock held by blkid/7167:
 #0:  (loop_ctl_mutex/1){+.+.}, at: [<ffffffff8373dc27>] lo_ioctl+0x87/0x1c70 drivers/block/loop.c:1405
2 locks held by syz-executor.4/7168:
 #0:  (loop_ctl_mutex/1){+.+.}, at: [<ffffffff8373dc27>] lo_ioctl+0x87/0x1c70 drivers/block/loop.c:1405
 #1:  (&bdev->bd_mutex){+.+.}, at: [<ffffffff82cab2af>] blkdev_reread_part+0x1f/0x40 block/ioctl.c:192
2 locks held by syz-executor.0/7169:
 #0:  (&bdev->bd_mutex){+.+.}, at: [<ffffffff819a83a5>] __blkdev_get+0x145/0x1120 fs/block_dev.c:1457
 #1:  (loop_index_mutex){+.+.}, at: [<ffffffff8373739d>] lo_open+0x1d/0xb0 drivers/block/loop.c:1624
1 lock held by syz-executor.3/7174:
 #0:  (&bdev->bd_mutex){+.+.}, at: [<ffffffff819a83a5>] __blkdev_get+0x145/0x1120 fs/block_dev.c:1457
2 locks held by blkid/7175:
 #0:  (&bdev->bd_mutex){+.+.}, at: [<ffffffff819a83a5>] __blkdev_get+0x145/0x1120 fs/block_dev.c:1457
 #1:  (loop_index_mutex){+.+.}, at: [<ffffffff8373739d>] lo_open+0x1d/0xb0 drivers/block/loop.c:1624
1 lock held by blkid/7176:
 #0:  (&bdev->bd_mutex){+.+.}, at: [<ffffffff819a83a5>] __blkdev_get+0x145/0x1120 fs/block_dev.c:1457
2 locks held by blkid/7177:
 #0:  (&bdev->bd_mutex){+.+.}, at: [<ffffffff819a83a5>] __blkdev_get+0x145/0x1120 fs/block_dev.c:1457
 #1:  (loop_index_mutex){+.+.}, at: [<ffffffff8373739d>] lo_open+0x1d/0xb0 drivers/block/loop.c:1624

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

NMI backtrace for cpu 1
CPU: 1 PID: 1007 Comm: khungtaskd Not tainted 4.14.114 #4
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x138/0x19c lib/dump_stack.c:53
 nmi_cpu_backtrace.cold+0x57/0x94 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x141/0x189 lib/nmi_backtrace.c:62
 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38
 trigger_all_cpu_backtrace include/linux/nmi.h:140 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:195 [inline]
 watchdog+0x5e7/0xb90 kernel/hung_task.c:274
 kthread+0x31c/0x430 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: 7026 Comm: kworker/u4:2 Not tainted 4.14.114 #4
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: bat_events batadv_nc_worker
task: ffff888087a80200 task.stack: ffff888097a38000
RIP: 0010:lock_release+0x0/0x940 kernel/locking/lockdep.c:4000
RSP: 0018:ffff888097a3fc48 EFLAGS: 00000297
RAX: ffff888087a80200 RBX: ffff8880a0f24648 RCX: 00000000a389885d
RDX: ffffffff86034dc5 RSI: 0000000000000001 RDI: ffff8880a0f24660
RBP: ffff888097a3fc58 R08: 0000000000001572 R09: ffffffff88c83f90
R10: ffff888087a80ad0 R11: ffff888087a80200 R12: ffff8880a0f24648
R13: dffffc0000000000 R14: ffffffff86035620 R15: ffff8880a133cc40
FS:  0000000000000000(0000) GS:ffff8880aee00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000007984ec CR3: 00000000a11e2000 CR4: 00000000001406f0
Call Trace:
 spin_unlock_bh include/linux/spinlock.h:362 [inline]
 batadv_nc_purge_paths+0x245/0x350 net/batman-adv/network-coding.c:479
 batadv_nc_worker+0x23d/0x6d0 net/batman-adv/network-coding.c:727
 process_one_work+0x868/0x1610 kernel/workqueue.c:2114
 worker_thread+0x5d9/0x1050 kernel/workqueue.c:2248
 kthread+0x31c/0x430 kernel/kthread.c:232
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:402
Code: c7 c7 a0 e4 24 89 e8 60 4c 3e 00 e9 ed fe ff ff 48 c7 c7 a0 e4 24 89 e8 4f 4c 3e 00 e9 84 fd ff ff 66 2e 0f 1f 84 00 00 00 00 00 <48> b8 00 00 00 00 00 fc ff df 55 48 89 e5 41 57 41 56 4c 8d 7d 

Crashes (128):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-linux-4-14 2019/04/28 03:42 linux-4.14.y fa5941f45d7e b617407b .config log report syz
ci2-linux-4-14 2019/04/19 20:23 linux-4.14.y 58b454ebf81e b0e8efcb .config log report syz
ci2-linux-4-14 2019/08/02 03:29 linux-4.14.y 10d6aa565d05 835dffe7 .config log report
ci2-linux-4-14 2019/06/12 03:32 linux-4.14.y 2bf3258a12af ea2f4006 .config log report
ci2-linux-4-14 2019/05/02 00:37 linux-4.14.y fa5941f45d7e 7516d9fa .config log report
ci2-linux-4-14 2019/05/01 22:33 linux-4.14.y fa5941f45d7e 7516d9fa .config log report
ci2-linux-4-14 2019/05/01 21:22 linux-4.14.y fa5941f45d7e 7516d9fa .config log report
ci2-linux-4-14 2019/05/01 21:00 linux-4.14.y fa5941f45d7e 7516d9fa .config log report
ci2-linux-4-14 2019/05/01 19:11 linux-4.14.y fa5941f45d7e 7516d9fa .config log report
ci2-linux-4-14 2019/05/01 14:05 linux-4.14.y fa5941f45d7e 618456b4 .config log report
ci2-linux-4-14 2019/05/01 11:47 linux-4.14.y fa5941f45d7e 618456b4 .config log report
ci2-linux-4-14 2019/04/30 23:23 linux-4.14.y fa5941f45d7e 618456b4 .config log report
ci2-linux-4-14 2019/04/30 12:49 linux-4.14.y fa5941f45d7e 20f16bef .config log report
ci2-linux-4-14 2019/04/30 10:58 linux-4.14.y fa5941f45d7e 20f16bef .config log report
ci2-linux-4-14 2019/04/30 05:48 linux-4.14.y fa5941f45d7e 20f16bef .config log report
ci2-linux-4-14 2019/04/30 00:48 linux-4.14.y fa5941f45d7e b617407b .config log report
ci2-linux-4-14 2019/04/29 23:39 linux-4.14.y fa5941f45d7e b617407b .config log report
ci2-linux-4-14 2019/04/29 11:50 linux-4.14.y fa5941f45d7e b617407b .config log report
ci2-linux-4-14 2019/04/29 09:56 linux-4.14.y fa5941f45d7e b617407b .config log report
ci2-linux-4-14 2019/04/29 08:15 linux-4.14.y fa5941f45d7e b617407b .config log report
ci2-linux-4-14 2019/04/29 06:38 linux-4.14.y fa5941f45d7e b617407b .config log report
ci2-linux-4-14 2019/04/28 22:40 linux-4.14.y fa5941f45d7e b617407b .config log report
ci2-linux-4-14 2019/04/28 13:33 linux-4.14.y fa5941f45d7e b617407b .config log report
ci2-linux-4-14 2019/04/28 09:24 linux-4.14.y fa5941f45d7e b617407b .config log report
ci2-linux-4-14 2019/04/27 22:34 linux-4.14.y fa5941f45d7e b617407b .config log report
ci2-linux-4-14 2019/04/27 17:27 linux-4.14.y fa5941f45d7e b617407b .config log report
ci2-linux-4-14 2019/04/27 10:24 linux-4.14.y fa5941f45d7e b617407b .config log report
ci2-linux-4-14 2019/04/27 08:05 linux-4.14.y 68d7a45eec10 b617407b .config log report
ci2-linux-4-14 2019/04/27 06:12 linux-4.14.y 68d7a45eec10 b617407b .config log report
ci2-linux-4-14 2019/04/27 05:02 linux-4.14.y 68d7a45eec10 b617407b .config log report
ci2-linux-4-14 2019/04/27 03:02 linux-4.14.y 68d7a45eec10 b617407b .config log report
ci2-linux-4-14 2019/04/27 01:17 linux-4.14.y 68d7a45eec10 b617407b .config log report
ci2-linux-4-14 2019/04/26 22:04 linux-4.14.y 68d7a45eec10 b617407b .config log report
ci2-linux-4-14 2019/04/26 15:51 linux-4.14.y 68d7a45eec10 b617407b .config log report
ci2-linux-4-14 2019/04/26 14:14 linux-4.14.y 68d7a45eec10 b617407b .config log report
ci2-linux-4-14 2019/04/26 11:05 linux-4.14.y 68d7a45eec10 b617407b .config log report
ci2-linux-4-14 2019/04/26 07:04 linux-4.14.y 68d7a45eec10 b617407b .config log report
ci2-linux-4-14 2019/04/26 06:31 linux-4.14.y 68d7a45eec10 b617407b .config log report
ci2-linux-4-14 2019/04/26 00:15 linux-4.14.y 68d7a45eec10 f46aabc8 .config log report
ci2-linux-4-14 2019/04/25 15:06 linux-4.14.y 68d7a45eec10 f46aabc8 .config log report
ci2-linux-4-14 2019/04/25 09:13 linux-4.14.y 68d7a45eec10 8e3c52b1 .config log report
ci2-linux-4-14 2019/04/25 04:59 linux-4.14.y 68d7a45eec10 8e3c52b1 .config log report
ci2-linux-4-14 2019/04/25 01:03 linux-4.14.y 68d7a45eec10 8e3c52b1 .config log report
ci2-linux-4-14 2019/04/24 20:51 linux-4.14.y 68d7a45eec10 8e3c52b1 .config log report
ci2-linux-4-14 2019/04/24 16:37 linux-4.14.y 68d7a45eec10 8e3c52b1 .config log report
ci2-linux-4-14 2019/04/24 10:29 linux-4.14.y 68d7a45eec10 8e3c52b1 .config log report
ci2-linux-4-14 2019/04/24 06:01 linux-4.14.y 68d7a45eec10 2398edea .config log report
ci2-linux-4-14 2019/04/11 15:01 linux-4.14.y 1ec8f1f0bffe 13030ef8 .config log report