Bluetooth: hci8 command 0x0419 tx timeout Bluetooth: hci7 command 0x0419 tx timeout Bluetooth: hci6 command 0x0406 tx timeout Bluetooth: hci8 command 0x0406 tx timeout Bluetooth: hci7 command 0x0406 tx timeout INFO: task systemd-udevd:4634 blocked for more than 140 seconds. Not tainted 4.14.290-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. systemd-udevd D25976 4634 1 0x00000304 Call Trace: context_switch kernel/sched/core.c:2811 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3387 schedule+0x8d/0x1b0 kernel/sched/core.c:3431 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3489 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x669/0x1310 kernel/locking/mutex.c:893 __blkdev_get+0x191/0x1090 fs/block_dev.c:1455 blkdev_get+0x88/0x890 fs/block_dev.c:1611 blkdev_open+0x1cc/0x250 fs/block_dev.c:1772 do_dentry_open+0x44b/0xec0 fs/open.c:777 vfs_open+0x105/0x220 fs/open.c:888 do_last fs/namei.c:3428 [inline] path_openat+0x628/0x2970 fs/namei.c:3569 do_filp_open+0x179/0x3c0 fs/namei.c:3603 do_sys_open+0x296/0x410 fs/open.c:1081 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7fc5e5b78840 RSP: 002b:00007ffd7c58f008 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 00007ffd7c58f0a0 RCX: 00007fc5e5b78840 RDX: 0000555f012c5fe3 RSI: 00000000000a0800 RDI: 0000555f02afa8a0 RBP: 00007ffd7c58f600 R08: 0000555f012c5670 R09: 0000000000000010 R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd7c58f1b0 R13: 0000555f02ae9010 R14: 0000555f02b03650 R15: 00007ffd7c58f080 INFO: task syz-executor.1:8019 blocked for more than 140 seconds. Not tainted 4.14.290-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D24552 8019 1 0x00000004 Call Trace: context_switch kernel/sched/core.c:2811 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3387 schedule+0x8d/0x1b0 kernel/sched/core.c:3431 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3489 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x669/0x1310 kernel/locking/mutex.c:893 lo_open+0x19/0xb0 drivers/block/loop.c:1634 __blkdev_get+0xa8c/0x1090 fs/block_dev.c:1537 blkdev_get+0x88/0x890 fs/block_dev.c:1611 blkdev_open+0x1cc/0x250 fs/block_dev.c:1772 do_dentry_open+0x44b/0xec0 fs/open.c:777 vfs_open+0x105/0x220 fs/open.c:888 do_last fs/namei.c:3428 [inline] path_openat+0x628/0x2970 fs/namei.c:3569 do_filp_open+0x179/0x3c0 fs/namei.c:3603 do_sys_open+0x296/0x410 fs/open.c:1081 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7f2ca0342194 RSP: 002b:00007ffcad5bdc20 EFLAGS: 00000293 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007ffcad5bdd20 RCX: 00007f2ca0342194 RDX: 0000000000000002 RSI: 00007ffcad5bdd60 RDI: 00000000ffffff9c RBP: 00007ffcad5bdd60 R08: 0000000000000000 R09: 00007ffcad5bdb30 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000002 R13: 000000000002f921 R14: 0000000000000009 R15: 00007ffcad5bdd60 INFO: task syz-executor.4:8024 blocked for more than 140 seconds. Not tainted 4.14.290-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D25632 8024 1 0x00000004 Call Trace: context_switch kernel/sched/core.c:2811 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3387 schedule+0x8d/0x1b0 kernel/sched/core.c:3431 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3489 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x669/0x1310 kernel/locking/mutex.c:893 lo_open+0x19/0xb0 drivers/block/loop.c:1634 __blkdev_get+0x306/0x1090 fs/block_dev.c:1470 blkdev_get+0x88/0x890 fs/block_dev.c:1611 blkdev_open+0x1cc/0x250 fs/block_dev.c:1772 do_dentry_open+0x44b/0xec0 fs/open.c:777 vfs_open+0x105/0x220 fs/open.c:888 do_last fs/namei.c:3428 [inline] path_openat+0x628/0x2970 fs/namei.c:3569 do_filp_open+0x179/0x3c0 fs/namei.c:3603 do_sys_open+0x296/0x410 fs/open.c:1081 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7fdb4e9be194 RSP: 002b:00007ffe3b2146a0 EFLAGS: 00000293 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007ffe3b2147a0 RCX: 00007fdb4e9be194 RDX: 0000000000000002 RSI: 00007ffe3b2147e0 RDI: 00000000ffffff9c RBP: 00007ffe3b2147e0 R08: 0000000000000000 R09: 00007ffe3b2145b0 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000002 R13: 000000000002f675 R14: 0000000000000014 R15: 00007ffe3b2147e0 INFO: task systemd-udevd:11434 blocked for more than 140 seconds. Not tainted 4.14.290-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. systemd-udevd D28912 11434 4634 0x00000300 Call Trace: context_switch kernel/sched/core.c:2811 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3387 schedule+0x8d/0x1b0 kernel/sched/core.c:3431 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3489 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x669/0x1310 kernel/locking/mutex.c:893 lo_open+0x19/0xb0 drivers/block/loop.c:1634 __blkdev_get+0xa8c/0x1090 fs/block_dev.c:1537 blkdev_get+0x88/0x890 fs/block_dev.c:1611 blkdev_open+0x1cc/0x250 fs/block_dev.c:1772 do_dentry_open+0x44b/0xec0 fs/open.c:777 vfs_open+0x105/0x220 fs/open.c:888 do_last fs/namei.c:3428 [inline] path_openat+0x628/0x2970 fs/namei.c:3569 do_filp_open+0x179/0x3c0 fs/namei.c:3603 do_sys_open+0x296/0x410 fs/open.c:1081 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7fc5e5b78840 RSP: 002b:00007ffd7c58e948 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 0000555f02afd160 RCX: 00007fc5e5b78840 RDX: 0000555f012c5fe3 RSI: 00000000000a0800 RDI: 0000555f02afe2e0 RBP: 00007ffd7c58eac0 R08: 0000555f012c5670 R09: 0000000000000010 R10: 0000555f012c5d0c R11: 0000000000000246 R12: 00007ffd7c58ea10 R13: 0000555f02aea870 R14: 0000000000000003 R15: 000000000000000e INFO: task syz-executor.5:11446 blocked for more than 140 seconds. Not tainted 4.14.290-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D28768 11446 8014 0x00000004 Call Trace: context_switch kernel/sched/core.c:2811 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3387 schedule+0x8d/0x1b0 kernel/sched/core.c:3431 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3489 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x669/0x1310 kernel/locking/mutex.c:893 loop_control_ioctl+0x181/0x3f0 drivers/block/loop.c:2007 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0x75a/0xff0 fs/ioctl.c:684 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7f8f1f04a279 RSP: 002b:00007f8f1d9bf168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f8f1f15cf80 RCX: 00007f8f1f04a279 RDX: 0000000000000002 RSI: 0000000000004c81 RDI: 0000000000000004 RBP: 00007f8f1f0a4189 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffce7f0762f R14: 00007f8f1d9bf300 R15: 0000000000022000 INFO: task syz-executor.2:11445 blocked for more than 140 seconds. Not tainted 4.14.290-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D28912 11445 8021 0x00000004 Call Trace: context_switch kernel/sched/core.c:2811 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3387 schedule+0x8d/0x1b0 kernel/sched/core.c:3431 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3489 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x669/0x1310 kernel/locking/mutex.c:893 blkdev_reread_part+0x1b/0x40 block/ioctl.c:192 loop_reread_partitions drivers/block/loop.c:624 [inline] loop_set_status+0xeeb/0x12b0 drivers/block/loop.c:1193 loop_set_status64+0x92/0xe0 drivers/block/loop.c:1311 lo_ioctl+0x587/0x1cd0 drivers/block/loop.c:1441 __blkdev_driver_ioctl block/ioctl.c:297 [inline] blkdev_ioctl+0x540/0x1830 block/ioctl.c:594 block_ioctl+0xd9/0x120 fs/block_dev.c:1893 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0x75a/0xff0 fs/ioctl.c:684 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7f07a0361037 RSP: 002b:00007f079ecd5ed8 EFLAGS: 00000202 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f079ecd5f20 RCX: 00007f07a0361037 RDX: 00007f079ecd6030 RSI: 0000000000004c04 RDI: 0000000000000009 RBP: 00007f07a03bb189 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 00007f079ecd6030 R13: 00007ffe234b2b5f R14: 00007f079ecd6300 R15: 0000000000022000 INFO: task syz-executor.3:11441 blocked for more than 140 seconds. Not tainted 4.14.290-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.3 D28912 11441 8023 0x00000004 Call Trace: context_switch kernel/sched/core.c:2811 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3387 schedule+0x8d/0x1b0 kernel/sched/core.c:3431 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3489 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x669/0x1310 kernel/locking/mutex.c:893 blkdev_put+0x27/0x4c0 fs/block_dev.c:1826 blkdev_close+0x86/0xb0 fs/block_dev.c:1875 __fput+0x25f/0x7a0 fs/file_table.c:210 task_work_run+0x11f/0x190 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:191 [inline] exit_to_usermode_loop+0x1ad/0x200 arch/x86/entry/common.c:164 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline] syscall_return_slowpath arch/x86/entry/common.c:270 [inline] do_syscall_64+0x4a3/0x640 arch/x86/entry/common.c:297 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7f373bbcdebb RSP: 002b:00007ffca5c2e7e0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 000000000000000b RCX: 00007f373bbcdebb RDX: 0000001b30920000 RSI: 0000001b30925df8 RDI: 000000000000000a RBP: 00007f373bd2f980 R08: 0000000000000000 R09: 00000000c07cd304 R10: 0019741913001dc7 R11: 0000000000000293 R12: 000000000002f925 R13: 00007ffca5c2e8e0 R14: 00007ffca5c2e900 R15: 0000000000000032 INFO: task syz-executor.3:11448 blocked for more than 140 seconds. Not tainted 4.14.290-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.3 D26432 11448 8023 0x00000004 Call Trace: context_switch kernel/sched/core.c:2811 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3387 schedule+0x8d/0x1b0 kernel/sched/core.c:3431 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3489 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x669/0x1310 kernel/locking/mutex.c:893 blkdev_put+0x27/0x4c0 fs/block_dev.c:1826 deactivate_locked_super+0x6c/0xd0 fs/super.c:319 mount_bdev+0x31f/0x360 fs/super.c:1136 mount_fs+0x92/0x2a0 fs/super.c:1237 vfs_kern_mount.part.0+0x5b/0x470 fs/namespace.c:1046 vfs_kern_mount fs/namespace.c:1036 [inline] do_new_mount fs/namespace.c:2572 [inline] do_mount+0xe65/0x2a30 fs/namespace.c:2905 SYSC_mount fs/namespace.c:3121 [inline] SyS_mount+0xa8/0x120 fs/namespace.c:3098 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7f373bc1c7aa RSP: 002b:00007f373a58ff88 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000020000480 RCX: 00007f373bc1c7aa RDX: 00000000200002c0 RSI: 0000000020000100 RDI: 00007f373a58ffe0 RBP: 00007f373a590020 R08: 00007f373a590020 R09: 00000000200002c0 R10: 0000000000000000 R11: 0000000000000202 R12: 00000000200002c0 R13: 0000000020000100 R14: 00007f373a58ffe0 R15: 00000000200000c0 INFO: task systemd-udevd:11444 blocked for more than 140 seconds. Not tainted 4.14.290-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. systemd-udevd D28712 11444 4634 0x00000300 Call Trace: context_switch kernel/sched/core.c:2811 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3387 schedule+0x8d/0x1b0 kernel/sched/core.c:3431 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3489 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x669/0x1310 kernel/locking/mutex.c:893 lo_release+0x1b/0x190 drivers/block/loop.c:1677 __blkdev_put+0x5aa/0x800 fs/block_dev.c:1803 blkdev_close+0x86/0xb0 fs/block_dev.c:1875 __fput+0x25f/0x7a0 fs/file_table.c:210 task_work_run+0x11f/0x190 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:191 [inline] exit_to_usermode_loop+0x1ad/0x200 arch/x86/entry/common.c:164 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline] syscall_return_slowpath arch/x86/entry/common.c:270 [inline] do_syscall_64+0x4a3/0x640 arch/x86/entry/common.c:297 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7fc5e5b78270 RSP: 002b:00007ffd7c58e928 EFLAGS: 00000246 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000007 RCX: 00007fc5e5b78270 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000007 RBP: 00007fc5e6a32710 R08: 0000555f02afcf00 R09: 0000555f02afcc00 R10: 00007fc5e6a328c0 R11: 0000000000000246 R12: 0000000000000000 R13: 0000555f02afec10 R14: 0000000000000003 R15: 000000000000000e INFO: task syz-executor.3:11533 blocked for more than 140 seconds. Not tainted 4.14.290-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.3 D25632 11533 1 0x00000004 Call Trace: context_switch kernel/sched/core.c:2811 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3387 schedule+0x8d/0x1b0 kernel/sched/core.c:3431 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3489 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x669/0x1310 kernel/locking/mutex.c:893 __blkdev_get+0x191/0x1090 fs/block_dev.c:1455 blkdev_get+0x88/0x890 fs/block_dev.c:1611 blkdev_open+0x1cc/0x250 fs/block_dev.c:1772 do_dentry_open+0x44b/0xec0 fs/open.c:777 vfs_open+0x105/0x220 fs/open.c:888 do_last fs/namei.c:3428 [inline] path_openat+0x628/0x2970 fs/namei.c:3569 do_filp_open+0x179/0x3c0 fs/namei.c:3603 do_sys_open+0x296/0x410 fs/open.c:1081 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7f1d18dd4194 RSP: 002b:00007fffd980bf70 EFLAGS: 00000293 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007fffd980c070 RCX: 00007f1d18dd4194 RDX: 0000000000000002 RSI: 00007fffd980c0b0 RDI: 00000000ffffff9c RBP: 00007fffd980c0b0 R08: 0000000000000000 R09: 00007fffd980be80 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000002 R13: 00007f1d18f02140 R14: 00007f1d18f02e48 R15: 00007fffd980c0b0 Showing all locks held in the system: 1 lock held by khungtaskd/1533: #0: (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4548 1 lock held by systemd-udevd/4634: #0: (&bdev->bd_mutex){+.+.}, at: [] __blkdev_get+0x191/0x1090 fs/block_dev.c:1455 2 locks held by agetty/7715: #0: (&tty->ldisc_sem){++++}, at: [] tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:284 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e3/0x1680 drivers/tty/n_tty.c:2156 2 locks held by syz-executor.1/8019: #0: (&bdev->bd_mutex){+.+.}, at: [] __blkdev_get+0x191/0x1090 fs/block_dev.c:1455 #1: (loop_index_mutex){+.+.}, at: [] lo_open+0x19/0xb0 drivers/block/loop.c:1634 2 locks held by syz-executor.4/8024: #0: (&bdev->bd_mutex){+.+.}, at: [] __blkdev_get+0x191/0x1090 fs/block_dev.c:1455 #1: (loop_index_mutex){+.+.}, at: [] lo_open+0x19/0xb0 drivers/block/loop.c:1634 2 locks held by systemd-udevd/11434: #0: (&bdev->bd_mutex){+.+.}, at: [] __blkdev_get+0x191/0x1090 fs/block_dev.c:1455 #1: (loop_index_mutex){+.+.}, at: [] lo_open+0x19/0xb0 drivers/block/loop.c:1634 2 locks held by syz-executor.5/11446: #0: (loop_index_mutex){+.+.}, at: [] loop_control_ioctl+0x67/0x3f0 drivers/block/loop.c:1993 #1: (&lo->lo_ctl_mutex){+.+.}, at: [] loop_control_ioctl+0x181/0x3f0 drivers/block/loop.c:2007 2 locks held by syz-executor.2/11445: #0: (&lo->lo_ctl_mutex/1){+.+.}, at: [] lo_ioctl+0x87/0x1cd0 drivers/block/loop.c:1414 #1: (&bdev->bd_mutex){+.+.}, at: [] blkdev_reread_part+0x1b/0x40 block/ioctl.c:192 1 lock held by syz-executor.3/11441: #0: (&bdev->bd_mutex){+.+.}, at: [] blkdev_put+0x27/0x4c0 fs/block_dev.c:1826 1 lock held by syz-executor.3/11448: #0: (&bdev->bd_mutex){+.+.}, at: [] blkdev_put+0x27/0x4c0 fs/block_dev.c:1826 2 locks held by systemd-udevd/11444: #0: (&bdev->bd_mutex){+.+.}, at: [] __blkdev_put+0xd8/0x800 fs/block_dev.c:1790 #1: (loop_index_mutex){+.+.}, at: [] lo_release+0x1b/0x190 drivers/block/loop.c:1677 1 lock held by syz-executor.3/11533: #0: (&bdev->bd_mutex){+.+.}, at: [] __blkdev_get+0x191/0x1090 fs/block_dev.c:1455 1 lock held by syz-executor.2/11536: #0: (&bdev->bd_mutex){+.+.}, at: [] __blkdev_get+0x191/0x1090 fs/block_dev.c:1455 2 locks held by syz-executor.5/11537: #0: (&bdev->bd_mutex){+.+.}, at: [] __blkdev_get+0x191/0x1090 fs/block_dev.c:1455 #1: (loop_index_mutex){+.+.}, at: [] lo_open+0x19/0xb0 drivers/block/loop.c:1634 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1533 Comm: khungtaskd Not tainted 4.14.290-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x1b2/0x281 lib/dump_stack.c:58 nmi_cpu_backtrace.cold+0x57/0x93 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x13a/0x180 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:140 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:195 [inline] watchdog+0x5b9/0xb40 kernel/hung_task.c:274 kthread+0x30d/0x420 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 0xffffffff8723f20e