INFO: task syz-executor.5:1857 blocked for more than 140 seconds. Not tainted 4.14.113+ #61 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D25160 1857 1 0x00000004 Call Trace: schedule+0x92/0x1c0 kernel/sched/core.c:3498 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3556 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x559/0x1430 kernel/locking/mutex.c:893 lo_ioctl+0x83/0x1970 drivers/block/loop.c:1405 __blkdev_driver_ioctl block/ioctl.c:297 [inline] blkdev_ioctl+0x4d9/0x1810 block/ioctl.c:594 block_ioctl+0xd9/0x120 fs/block_dev.c:1881 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0xabe/0x1040 fs/ioctl.c:684 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692 do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289 INFO: task syz-executor.2:1866 blocked for more than 140 seconds. Not tainted 4.14.113+ #61 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D25592 1866 1 0x00000004 Call Trace: schedule+0x92/0x1c0 kernel/sched/core.c:3498 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3556 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x559/0x1430 kernel/locking/mutex.c:893 lo_open+0x19/0xb0 drivers/block/loop.c:1624 __blkdev_get+0x267/0xf90 fs/block_dev.c:1472 blkdev_get+0x97/0x8b0 fs/block_dev.c:1612 blkdev_open+0x1cc/0x250 fs/block_dev.c:1770 do_dentry_open+0x44e/0xdf0 fs/open.c:770 vfs_open+0x105/0x230 fs/open.c:884 do_last fs/namei.c:3455 [inline] path_openat+0xb6b/0x2b70 fs/namei.c:3597 do_filp_open+0x1a1/0x280 fs/namei.c:3631 do_sys_open+0x2ca/0x590 fs/open.c:1077 do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289 INFO: task syz-executor.4:1867 blocked for more than 140 seconds. Not tainted 4.14.113+ #61 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D25640 1867 1 0x00000004 Call Trace: schedule+0x92/0x1c0 kernel/sched/core.c:3498 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3556 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x559/0x1430 kernel/locking/mutex.c:893 __blkdev_get+0xf3/0xf90 fs/block_dev.c:1457 blkdev_get+0x97/0x8b0 fs/block_dev.c:1612 blkdev_open+0x1cc/0x250 fs/block_dev.c:1770 do_dentry_open+0x44e/0xdf0 fs/open.c:770 vfs_open+0x105/0x230 fs/open.c:884 do_last fs/namei.c:3455 [inline] path_openat+0xb6b/0x2b70 fs/namei.c:3597 do_filp_open+0x1a1/0x280 fs/namei.c:3631 do_sys_open+0x2ca/0x590 fs/open.c:1077 do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289 INFO: task blkid:2365 blocked for more than 140 seconds. Not tainted 4.14.113+ #61 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. blkid D28808 2365 3427 0x00000004 Call Trace: schedule+0x92/0x1c0 kernel/sched/core.c:3498 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3556 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x559/0x1430 kernel/locking/mutex.c:893 __lo_release drivers/block/loop.c:1644 [inline] lo_release+0x78/0x190 drivers/block/loop.c:1668 __blkdev_put+0x518/0x6d0 fs/block_dev.c:1791 blkdev_close+0x86/0xb0 fs/block_dev.c:1863 __fput+0x25e/0x700 fs/file_table.c:210 task_work_run+0x118/0x190 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:191 [inline] exit_to_usermode_loop+0x13b/0x160 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+0x372/0x4b0 arch/x86/entry/common.c:294 INFO: task syz-executor.1:2373 blocked for more than 140 seconds. Not tainted 4.14.113+ #61 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D29248 2373 1852 0x00000004 Call Trace: schedule+0x92/0x1c0 kernel/sched/core.c:3498 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3556 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x559/0x1430 kernel/locking/mutex.c:893 blkdev_reread_part+0x1b/0x40 block/ioctl.c:192 loop_reread_partitions+0x72/0x80 drivers/block/loop.c:615 loop_set_status+0xbff/0x11f0 drivers/block/loop.c:1184 INFO: task blkid:2377 blocked for more than 140 seconds. Not tainted 4.14.113+ #61 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. blkid D29248 2377 353 0x00000004 Call Trace: schedule+0x92/0x1c0 kernel/sched/core.c:3498 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3556 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x559/0x1430 kernel/locking/mutex.c:893 lo_open+0x19/0xb0 drivers/block/loop.c:1624 __blkdev_get+0x963/0xf90 fs/block_dev.c:1537 blkdev_get+0x97/0x8b0 fs/block_dev.c:1612 blkdev_open+0x1cc/0x250 fs/block_dev.c:1770 do_dentry_open+0x44e/0xdf0 fs/open.c:770 vfs_open+0x105/0x230 fs/open.c:884 do_last fs/namei.c:3455 [inline] path_openat+0xb6b/0x2b70 fs/namei.c:3597 do_filp_open+0x1a1/0x280 fs/namei.c:3631 do_sys_open+0x2ca/0x590 fs/open.c:1077 do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289 Showing all locks held in the system: 1 lock held by khungtaskd/23: #0: (tasklist_lock){.+.+}, at: [<000000001bf5c518>] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4544 2 locks held by getty/1763: #0: (&tty->ldisc_sem){++++}, at: [<0000000032ab19d3>] tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:284 #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000a6554e06>] n_tty_read+0x1f7/0x1700 drivers/tty/n_tty.c:2156 1 lock held by syz-executor.5/1857: #0: (loop_ctl_mutex/1){+.+.}, at: [<00000000a189d507>] lo_ioctl+0x83/0x1970 drivers/block/loop.c:1405 2 locks held by syz-executor.2/1866: #0: (&bdev->bd_mutex){+.+.}, at: [<000000009aa04a8d>] __blkdev_get+0xf3/0xf90 fs/block_dev.c:1457 #1: (loop_index_mutex){+.+.}, at: [<0000000044e34b46>] lo_open+0x19/0xb0 drivers/block/loop.c:1624 1 lock held by syz-executor.4/1867: #0: (&bdev->bd_mutex){+.+.}, at: [<000000009aa04a8d>] __blkdev_get+0xf3/0xf90 fs/block_dev.c:1457 3 locks held by blkid/2365: #0: (&bdev->bd_mutex){+.+.}, at: [<000000009160c27d>] __blkdev_put+0xb1/0x6d0 fs/block_dev.c:1778 #1: (loop_index_mutex){+.+.}, at: [<0000000038d46c8d>] lo_release+0x19/0x190 drivers/block/loop.c:1667 #2: (loop_ctl_mutex#2){+.+.}, at: [<00000000e1298c82>] __lo_release drivers/block/loop.c:1644 [inline] #2: (loop_ctl_mutex#2){+.+.}, at: [<00000000e1298c82>] lo_release+0x78/0x190 drivers/block/loop.c:1668 2 locks held by syz-executor.1/2373: #0: (loop_ctl_mutex/1){+.+.}, at: [<00000000a189d507>] lo_ioctl+0x83/0x1970 drivers/block/loop.c:1405 #1: (&bdev->bd_mutex){+.+.}, at: [<0000000074c3f6d9>] blkdev_reread_part+0x1b/0x40 block/ioctl.c:192 2 locks held by blkid/2377: #0: (&bdev->bd_mutex){+.+.}, at: [<000000009aa04a8d>] __blkdev_get+0xf3/0xf90 fs/block_dev.c:1457 #1: (loop_index_mutex){+.+.}, at: [<0000000044e34b46>] lo_open+0x19/0xb0 drivers/block/loop.c:1624 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 23 Comm: khungtaskd Not tainted 4.14.113+ #61 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0xb9/0x10e lib/dump_stack.c:53 nmi_cpu_backtrace.cold+0x47/0x86 lib/nmi_backtrace.c:101 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 7634 Comm: syz-executor.3 Not tainted 4.14.113+ #61 task: 00000000dced0c97 task.stack: 000000004cf5aed6 RIP: 0033:0x40158b RSP: 002b:00007f66c6b97690 EFLAGS: 00000202 RAX: 000000004400bad5 RBX: 000000000000000b RCX: 0000000000458da9 RDX: 0000000000000000 RSI: 00007f66c6b976c0 RDI: 000000000000000b RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: ffffffff00000002 R14: 00000000305f6576 R15: 616c735f646e6f62 FS: 00007f66c6b98700(0000) GS:ffff8881dbb00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000001aa3000 CR3: 00000001d655c002 CR4: 00000000001606a0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600