protocol 88fb is buggy, dev hsr_slave_0
protocol 88fb is buggy, dev hsr_slave_1
protocol 88fb is buggy, dev hsr_slave_1
protocol 88fb is buggy, dev hsr_slave_0
protocol 88fb is buggy, dev hsr_slave_1
INFO: task syz-executor.0:6858 blocked for more than 140 seconds.
      Not tainted 4.14.155-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.0  D24992  6858      1 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2808 [inline]
 __schedule+0x7b8/0x1cd0 kernel/sched/core.c:3384
 schedule+0x92/0x1c0 kernel/sched/core.c:3428
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3486
 __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:614
 loop_clr_fd+0x844/0xae0 drivers/block/loop.c:1068
 lo_ioctl+0x8ea/0x1ce0 drivers/block/loop.c:1414
 __blkdev_driver_ioctl block/ioctl.c:297 [inline]
 blkdev_ioctl+0x96b/0x1860 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+0x7ae/0x1060 fs/ioctl.c:684
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692
 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x45a4a7
RSP: 002b:00007ffc223e9cc8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045a4a7
RDX: 0000000000000000 RSI: 0000000000004c01 RDI: 0000000000000003
RBP: 0000000000000152 R08: 0000000000000000 R09: 000000000000000a
R10: 0000000000000075 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffc223e9d00 R14: 00000000000421c6 R15: 00007ffc223e9d10
INFO: task syz-executor.1:6864 blocked for more than 140 seconds.
      Not tainted 4.14.155-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.1  D24992  6864      1 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2808 [inline]
 __schedule+0x7b8/0x1cd0 kernel/sched/core.c:3384
 schedule+0x92/0x1c0 kernel/sched/core.c:3428
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3486
 __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+0x73b/0xeb0 fs/open.c:777
 vfs_open+0x105/0x220 fs/open.c:891
 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:1084
 SYSC_open fs/open.c:1102 [inline]
 SyS_open+0x2d/0x40 fs/open.c:1097
 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x4143b0
RSP: 002b:00007ffe8bee4318 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00000000000427dd RCX: 00000000004143b0
RDX: 00007ffe8bee43aa RSI: 0000000000000002 RDI: 00007ffe8bee43a0
RBP: 0000000000000137 R08: 0000000000000000 R09: 000000000000000a
R10: 0000000000000075 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffe8bee4350 R14: 00000000000425df R15: 00007ffe8bee4360
INFO: task syz-executor.4:6867 blocked for more than 140 seconds.
      Not tainted 4.14.155-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.4  D24992  6867      1 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2808 [inline]
 __schedule+0x7b8/0x1cd0 kernel/sched/core.c:3384
 schedule+0x92/0x1c0 kernel/sched/core.c:3428
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3486
 __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+0x73b/0xeb0 fs/open.c:777
 vfs_open+0x105/0x220 fs/open.c:891
 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:1084
 SYSC_open fs/open.c:1102 [inline]
 SyS_open+0x2d/0x40 fs/open.c:1097
 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x4143b0
RSP: 002b:00007ffdfb7b11a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00000000000428ca RCX: 00000000004143b0
RDX: 00007ffdfb7b123a RSI: 0000000000000002 RDI: 00007ffdfb7b1230
RBP: 0000000000000146 R08: 0000000000000000 R09: 000000000000000a
R10: 0000000000000075 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffdfb7b11e0 R14: 000000000004259e R15: 00007ffdfb7b11f0
INFO: task syz-executor.3:8104 blocked for more than 140 seconds.
      Not tainted 4.14.155-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.3  D25232  8104      1 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2808 [inline]
 __schedule+0x7b8/0x1cd0 kernel/sched/core.c:3384
 schedule+0x92/0x1c0 kernel/sched/core.c:3428
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3486
 __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+0x73b/0xeb0 fs/open.c:777
 vfs_open+0x105/0x220 fs/open.c:891
 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:1084
 SYSC_open fs/open.c:1102 [inline]
 SyS_open+0x2d/0x40 fs/open.c:1097
 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x4143b0
RSP: 002b:00007fff454b51d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 0000000000042927 RCX: 00000000004143b0
RDX: 00007fff454b526a RSI: 0000000000000002 RDI: 00007fff454b5260
RBP: 0000000000000124 R08: 0000000000000000 R09: 000000000000000a
R10: 0000000000000075 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fff454b5210 R14: 00000000000425ed R15: 00007fff454b5220
INFO: task syz-executor.5:9898 blocked for more than 140 seconds.
      Not tainted 4.14.155-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.5  D25232  9898      1 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2808 [inline]
 __schedule+0x7b8/0x1cd0 kernel/sched/core.c:3384
 schedule+0x92/0x1c0 kernel/sched/core.c:3428
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3486
 __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+0x2c7/0x1120 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+0x73b/0xeb0 fs/open.c:777
 vfs_open+0x105/0x220 fs/open.c:891
 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:1084
 SYSC_open fs/open.c:1102 [inline]
 SyS_open+0x2d/0x40 fs/open.c:1097
 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x4143b0
RSP: 002b:00007fff7f4bfc88 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 0000000000042614 RCX: 00000000004143b0
RDX: 00007fff7f4bfd1a RSI: 0000000000000002 RDI: 00007fff7f4bfd10
RBP: 0000000000000014 R08: 0000000000000000 R09: 000000000000000a
R10: 0000000000000075 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fff7f4bfcc0 R14: 00000000000422d5 R15: 00007fff7f4bfcd0
INFO: task blkid:10078 blocked for more than 140 seconds.
      Not tainted 4.14.155-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
blkid           D29040 10078   9114 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2808 [inline]
 __schedule+0x7b8/0x1cd0 kernel/sched/core.c:3384
 schedule+0x92/0x1c0 kernel/sched/core.c:3428
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3486
 __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+0x2c7/0x1120 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+0x73b/0xeb0 fs/open.c:777
 vfs_open+0x105/0x220 fs/open.c:891
 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:1084
 SYSC_open fs/open.c:1102 [inline]
 SyS_open+0x2d/0x40 fs/open.c:1097
 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x7fc5dca67120
RSP: 002b:00007ffe03ee1068 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fc5dca67120
RDX: 00007ffe03ee2f34 RSI: 0000000000000000 RDI: 00007ffe03ee2f34
RBP: 0000000000000000 R08: 0000000000000078 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000001597030
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000005
INFO: task blkid:10081 blocked for more than 140 seconds.
      Not tainted 4.14.155-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
blkid           D29040 10081   9950 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2808 [inline]
 __schedule+0x7b8/0x1cd0 kernel/sched/core.c:3384
 schedule+0x92/0x1c0 kernel/sched/core.c:3428
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3486
 __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+0x2c7/0x1120 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+0x73b/0xeb0 fs/open.c:777
 vfs_open+0x105/0x220 fs/open.c:891
 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:1084
 SYSC_open fs/open.c:1102 [inline]
 SyS_open+0x2d/0x40 fs/open.c:1097
 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x7f890d32d120
RSP: 002b:00007ffc334e22d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f890d32d120
RDX: 00007ffc334e2f34 RSI: 0000000000000000 RDI: 00007ffc334e2f34
RBP: 0000000000000000 R08: 0000000000000078 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000178e030
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000005
INFO: task syz-executor.2:10083 blocked for more than 140 seconds.
      Not tainted 4.14.155-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.2  D28096 10083   8435 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2808 [inline]
 __schedule+0x7b8/0x1cd0 kernel/sched/core.c:3384
 schedule+0x92/0x1c0 kernel/sched/core.c:3428
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3486
 __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
 loop_control_ioctl+0x153/0x2f0 drivers/block/loop.c:1997
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0x7ae/0x1060 fs/ioctl.c:684
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692
 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x45a639
RSP: 002b:00007f1e71b72c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045a639
RDX: 0000000000000000 RSI: 0000000000004c81 RDI: 0000000000000008
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f1e71b736d4
R13: 00000000004c409c R14: 00000000004d8698 R15: 00000000ffffffff
INFO: task syz-executor.2:10100 blocked for more than 140 seconds.
      Not tainted 4.14.155-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.2  D29072 10100   8435 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2808 [inline]
 __schedule+0x7b8/0x1cd0 kernel/sched/core.c:3384
 schedule+0x92/0x1c0 kernel/sched/core.c:3428
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3486
 __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
 loop_control_ioctl+0x65/0x2f0 drivers/block/loop.c:1983
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0x7ae/0x1060 fs/ioctl.c:684
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692
 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x45a639
RSP: 002b:00007f1e71b30c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045a639
RDX: 0000000000000000 RSI: 0000000000004c80 RDI: 0000000000000009
RBP: 000000000075c070 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f1e71b316d4
R13: 00000000004c4071 R14: 00000000004d8668 R15: 00000000ffffffff
INFO: task blkid:10085 blocked for more than 140 seconds.
      Not tainted 4.14.155-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
blkid           D28688 10085   9955 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2808 [inline]
 __schedule+0x7b8/0x1cd0 kernel/sched/core.c:3384
 schedule+0x92/0x1c0 kernel/sched/core.c:3428
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3486
 __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+0x2c7/0x1120 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+0x73b/0xeb0 fs/open.c:777
 vfs_open+0x105/0x220 fs/open.c:891
 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:1084
 SYSC_open fs/open.c:1102 [inline]
 SyS_open+0x2d/0x40 fs/open.c:1097
 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x7f1b66f8f120
RSP: 002b:00007ffe1ef29f78 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f1b66f8f120
RDX: 00007ffe1ef2bf34 RSI: 0000000000000000 RDI: 00007ffe1ef2bf34
RBP: 0000000000000000 R08: 0000000000000078 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000dd3030
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000005

Showing all locks held in the system:
1 lock held by khungtaskd/1017:
 #0:  (tasklist_lock){.+.+}, at: [<ffffffff8148bca8>] debug_show_all_locks+0x7f/0x21f kernel/locking/lockdep.c:4544
2 locks held by getty/6814:
 #0:  (&tty->ldisc_sem){++++}, at: [<ffffffff861ceed3>] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff83114f46>] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156
2 locks held by getty/6815:
 #0:  (&tty->ldisc_sem){++++}, at: [<ffffffff861ceed3>] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff83114f46>] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156
2 locks held by getty/6816:
 #0:  (&tty->ldisc_sem){++++}, at: [<ffffffff861ceed3>] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff83114f46>] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156
2 locks held by getty/6817:
 #0:  (&tty->ldisc_sem){++++}, at: [<ffffffff861ceed3>] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff83114f46>] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156
2 locks held by getty/6818:
 #0:  (&tty->ldisc_sem){++++}, at: [<ffffffff861ceed3>] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff83114f46>] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156
2 locks held by getty/6819:
 #0:  (&tty->ldisc_sem){++++}, at: [<ffffffff861ceed3>] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff83114f46>] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156
2 locks held by getty/6820:
 #0:  (&tty->ldisc_sem){++++}, at: [<ffffffff861ceed3>] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff83114f46>] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156
2 locks held by syz-executor.0/6858:
 #0:  (&lo->lo_ctl_mutex/1){+.+.}, at: [<ffffffff8373a29f>] lo_ioctl+0x8f/0x1ce0 drivers/block/loop.c:1404
 #1:  (&bdev->bd_mutex){+.+.}, at: [<ffffffff82cb2e0f>] blkdev_reread_part+0x1f/0x40 block/ioctl.c:192
1 lock held by syz-executor.1/6864:
 #0:  (&bdev->bd_mutex){+.+.}, at: [<ffffffff819adab5>] __blkdev_get+0x145/0x1120 fs/block_dev.c:1457
1 lock held by syz-executor.4/6867:
 #0:  (&bdev->bd_mutex){+.+.}, at: [<ffffffff819adab5>] __blkdev_get+0x145/0x1120 fs/block_dev.c:1457
1 lock held by syz-executor.3/8104:
 #0:  (&bdev->bd_mutex){+.+.}, at: [<ffffffff819adab5>] __blkdev_get+0x145/0x1120 fs/block_dev.c:1457
2 locks held by syz-executor.5/9898:
 #0:  (&bdev->bd_mutex){+.+.}, at: [<ffffffff819adab5>] __blkdev_get+0x145/0x1120 fs/block_dev.c:1457
 #1:  (loop_index_mutex){+.+.}, at: [<ffffffff83733a4d>] lo_open+0x1d/0xb0 drivers/block/loop.c:1624
2 locks held by blkid/10078:
 #0:  (&bdev->bd_mutex){+.+.}, at: [<ffffffff819adab5>] __blkdev_get+0x145/0x1120 fs/block_dev.c:1457
 #1:  (loop_index_mutex){+.+.}, at: [<ffffffff83733a4d>] lo_open+0x1d/0xb0 drivers/block/loop.c:1624
2 locks held by blkid/10081:
 #0:  (&bdev->bd_mutex){+.+.}, at: [<ffffffff819adab5>] __blkdev_get+0x145/0x1120 fs/block_dev.c:1457
 #1:  (loop_index_mutex){+.+.}, at: [<ffffffff83733a4d>] lo_open+0x1d/0xb0 drivers/block/loop.c:1624
2 locks held by syz-executor.2/10083:
 #0:  (loop_index_mutex){+.+.}, at: [<ffffffff83739e25>] loop_control_ioctl+0x65/0x2f0 drivers/block/loop.c:1983
 #1:  (&lo->lo_ctl_mutex#2){+.+.}, at: [<ffffffff83739f13>] loop_control_ioctl+0x153/0x2f0 drivers/block/loop.c:1997
1 lock held by syz-executor.2/10100:
 #0:  (loop_index_mutex){+.+.}, at: [<ffffffff83739e25>] loop_control_ioctl+0x65/0x2f0 drivers/block/loop.c:1983
2 locks held by blkid/10085:
 #0:  (&bdev->bd_mutex){+.+.}, at: [<ffffffff819adab5>] __blkdev_get+0x145/0x1120 fs/block_dev.c:1457
 #1:  (loop_index_mutex){+.+.}, at: [<ffffffff83733a4d>] lo_open+0x1d/0xb0 drivers/block/loop.c:1624
2 locks held by blkid/10086:
 #0:  (&bdev->bd_mutex){+.+.}, at: [<ffffffff819adab5>] __blkdev_get+0x145/0x1120 fs/block_dev.c:1457
 #1:  (loop_index_mutex){+.+.}, at: [<ffffffff83733a4d>] lo_open+0x1d/0xb0 drivers/block/loop.c:1624
2 locks held by blkid/10092:
 #0:  (&bdev->bd_mutex){+.+.}, at: [<ffffffff819adab5>] __blkdev_get+0x145/0x1120 fs/block_dev.c:1457
 #1:  (loop_index_mutex){+.+.}, at: [<ffffffff83733a4d>] lo_open+0x1d/0xb0 drivers/block/loop.c:1624

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

NMI backtrace for cpu 0
CPU: 0 PID: 1017 Comm: khungtaskd Not tainted 4.14.155-syzkaller #0
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+0x142/0x197 lib/dump_stack.c:58
 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+0x319/0x430 kernel/kthread.c:232
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1 skipped: idling at pc 0xffffffff861cf9be