INFO: task syz-executor.4:1835 blocked for more than 140 seconds. Not tainted 4.14.140+ #38 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D25008 1835 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+0x595/0x13e0 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/0xe20 fs/open.c:789 vfs_open+0x105/0x230 fs/open.c:903 do_last fs/namei.c:3455 [inline] path_openat+0xb6c/0x2be0 fs/namei.c:3597 do_filp_open+0x1a1/0x280 fs/namei.c:3631 do_sys_open+0x2ca/0x590 fs/open.c:1096 do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x413740 RSP: 002b:00007ffe21175728 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 000000000001a5e8 RCX: 0000000000413740 RDX: 00007ffe211757ba RSI: 0000000000000002 RDI: 00007ffe211757b0 RBP: 0000000000000042 R08: 0000000000000000 R09: 000000000000000a R10: 0000000000000075 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffe21175760 R14: 000000000001a56a R15: 00007ffe21175770 INFO: task syz-executor.2:1838 blocked for more than 140 seconds. Not tainted 4.14.140+ #38 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D25312 1838 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+0x595/0x13e0 kernel/locking/mutex.c:893 lo_open+0x19/0xb0 drivers/block/loop.c:1623 __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/0xe20 fs/open.c:789 vfs_open+0x105/0x230 fs/open.c:903 do_last fs/namei.c:3455 [inline] path_openat+0xb6c/0x2be0 fs/namei.c:3597 do_filp_open+0x1a1/0x280 fs/namei.c:3631 do_sys_open+0x2ca/0x590 fs/open.c:1096 do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x413740 RSP: 002b:00007fffb5ed0e58 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 000000000001a7e9 RCX: 0000000000413740 RDX: 00007fffb5ed0eea RSI: 0000000000000002 RDI: 00007fffb5ed0ee0 RBP: 000000000000002f R08: 0000000000000000 R09: 000000000000000a R10: 0000000000000075 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fffb5ed0e90 R14: 000000000001a3d9 R15: 00007fffb5ed0ea0 INFO: task syz-executor.3:1840 blocked for more than 140 seconds. Not tainted 4.14.140+ #38 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.3 D25192 1840 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+0x595/0x13e0 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/0xe20 fs/open.c:789 vfs_open+0x105/0x230 fs/open.c:903 do_last fs/namei.c:3455 [inline] path_openat+0xb6c/0x2be0 fs/namei.c:3597 do_filp_open+0x1a1/0x280 fs/namei.c:3631 do_sys_open+0x2ca/0x590 fs/open.c:1096 do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x413740 RSP: 002b:00007ffde3e393d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 000000000001aa14 RCX: 0000000000413740 RDX: 00007ffde3e3946a RSI: 0000000000000002 RDI: 00007ffde3e39460 RBP: 000000000000004e R08: 0000000000000000 R09: 000000000000000a R10: 0000000000000075 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffde3e39410 R14: 000000000001aa10 R15: 00007ffde3e39420 INFO: task syz-executor.1:1841 blocked for more than 140 seconds. Not tainted 4.14.140+ #38 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D25312 1841 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+0x595/0x13e0 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/0xe20 fs/open.c:789 vfs_open+0x105/0x230 fs/open.c:903 do_last fs/namei.c:3455 [inline] path_openat+0xb6c/0x2be0 fs/namei.c:3597 do_filp_open+0x1a1/0x280 fs/namei.c:3631 do_sys_open+0x2ca/0x590 fs/open.c:1096 do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x413740 RSP: 002b:00007ffe63054498 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 000000000001a636 RCX: 0000000000413740 RDX: 00007ffe6305452a RSI: 0000000000000002 RDI: 00007ffe63054520 RBP: 0000000000000035 R08: 0000000000000000 R09: 000000000000000a R10: 0000000000000075 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffe630544d0 R14: 000000000001a56c R15: 00007ffe630544e0 INFO: task syz-executor.0:3565 blocked for more than 140 seconds. Not tainted 4.14.140+ #38 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D25488 3565 3237 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+0x595/0x13e0 kernel/locking/mutex.c:893 blkdev_reread_part+0x1b/0x40 block/ioctl.c:192 loop_reread_partitions+0x7f/0x90 drivers/block/loop.c:614 loop_clr_fd+0x835/0xad0 drivers/block/loop.c:1068 lo_ioctl+0x460/0x1a30 drivers/block/loop.c:1414 __blkdev_driver_ioctl block/ioctl.c:297 [inline] blkdev_ioctl+0x8d0/0x1870 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/0x520 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x4596e7 RSP: 002b:00007f77747cf9f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f77747d06d4 RCX: 00000000004596e7 RDX: 0000000000000000 RSI: 0000000000004c01 RDI: 0000000000000006 RBP: 0000000000000000 R08: 0000000000000000 R09: 000000000000000c R10: 0000000000000064 R11: 0000000000000246 R12: 0000000000000005 R13: 0000000000000000 R14: 0000000000000006 R15: 0000000000000001 INFO: task syz-executor.0:3580 blocked for more than 140 seconds. Not tainted 4.14.140+ #38 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D28432 3580 3237 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+0x595/0x13e0 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/0xe20 fs/open.c:789 vfs_open+0x105/0x230 fs/open.c:903 do_last fs/namei.c:3455 [inline] path_openat+0xb6c/0x2be0 fs/namei.c:3597 do_filp_open+0x1a1/0x280 fs/namei.c:3631 do_sys_open+0x2ca/0x590 fs/open.c:1096 do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x413761 RSP: 002b:00007f777478d9f0 EFLAGS: 00000293 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 00007f777478e6d4 RCX: 0000000000413761 RDX: 00007f777478dbaa RSI: 0000000000000002 RDI: 00007f777478dba0 RBP: 0000000000000001 R08: 0000000000000000 R09: 000000000000000a R10: 0000000000000075 R11: 0000000000000293 R12: 0000000000000005 R13: 0000000000000005 R14: 00007f777478e6d4 R15: 00000000ffffffff INFO: task syz-executor.0:3607 blocked for more than 140 seconds. Not tainted 4.14.140+ #38 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D28624 3607 3237 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+0x595/0x13e0 kernel/locking/mutex.c:893 __blkdev_get+0xf3/0xf90 fs/block_dev.c:1457 __blkdev_get+0x6d6/0xf90 fs/block_dev.c:1517 blkdev_get+0x97/0x8b0 fs/block_dev.c:1612 blkdev_open+0x1cc/0x250 fs/block_dev.c:1770 do_dentry_open+0x44e/0xe20 fs/open.c:789 vfs_open+0x105/0x230 fs/open.c:903 do_last fs/namei.c:3455 [inline] path_openat+0xb6c/0x2be0 fs/namei.c:3597 do_filp_open+0x1a1/0x280 fs/namei.c:3631 do_sys_open+0x2ca/0x590 fs/open.c:1096 do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x459879 RSP: 002b:00007f777474bc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459879 RDX: 0000000000000158 RSI: 0000000000000400 RDI: 0000000020003100 RBP: 000000000075c1c0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f777474c6d4 R13: 00000000004f907f R14: 00000000004dac90 R15: 00000000ffffffff INFO: task syz-executor.5:3591 blocked for more than 140 seconds. Not tainted 4.14.140+ #38 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D28416 3591 3243 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+0x595/0x13e0 kernel/locking/mutex.c:893 loop_control_ioctl+0x183/0x310 drivers/block/loop.c:1996 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/0x520 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x459879 RSP: 002b:00007f83baffec78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459879 RDX: 0000000000000000 RSI: 0000000000004c81 RDI: 0000000000000006 RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f83bafff6d4 R13: 00000000004c2fd2 R14: 00000000004d6718 R15: 00000000ffffffff INFO: task blkid:3592 blocked for more than 140 seconds. Not tainted 4.14.140+ #38 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. blkid D28992 3592 3557 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+0x595/0x13e0 kernel/locking/mutex.c:893 lo_open+0x19/0xb0 drivers/block/loop.c:1623 __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/0xe20 fs/open.c:789 vfs_open+0x105/0x230 fs/open.c:903 do_last fs/namei.c:3455 [inline] path_openat+0xb6c/0x2be0 fs/namei.c:3597 do_filp_open+0x1a1/0x280 fs/namei.c:3631 do_sys_open+0x2ca/0x590 fs/open.c:1096 do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x7f920d031120 RSP: 002b:00007ffcd0103d58 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f920d031120 RDX: 00007ffcd0105f34 RSI: 0000000000000000 RDI: 00007ffcd0105f34 RBP: 0000000000000000 R08: 0000000000000078 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000001781030 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000005 INFO: task blkid:3593 blocked for more than 140 seconds. Not tainted 4.14.140+ #38 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. blkid D29136 3593 3009 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+0x595/0x13e0 kernel/locking/mutex.c:893 lo_open+0x19/0xb0 drivers/block/loop.c:1623 __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/0xe20 fs/open.c:789 vfs_open+0x105/0x230 fs/open.c:903 do_last fs/namei.c:3455 [inline] path_openat+0xb6c/0x2be0 fs/namei.c:3597 do_filp_open+0x1a1/0x280 fs/namei.c:3631 do_sys_open+0x2ca/0x590 fs/open.c:1096 do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x7f45e26ac120 RSP: 002b:00007ffede0cdfe8 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f45e26ac120 RDX: 00007ffede0cff34 RSI: 0000000000000000 RDI: 00007ffede0cff34 RBP: 0000000000000000 R08: 0000000000000078 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000022df030 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000005 Showing all locks held in the system: 1 lock held by khungtaskd/23: #0: (tasklist_lock){.+.+}, at: [<00000000e1f8ca94>] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4541 1 lock held by rsyslogd/1628: #0: (&f->f_pos_lock){+.+.}, at: [<0000000058db90de>] __fdget_pos+0xb5/0xd0 fs/file.c:769 2 locks held by getty/1756: #0: (&tty->ldisc_sem){++++}, at: [<000000008d66a6e8>] tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:284 #1: (&ldata->atomic_read_lock){+.+.}, at: [<000000009ab81f0d>] n_tty_read+0x1f7/0x1700 drivers/tty/n_tty.c:2156 1 lock held by syz-executor.4/1835: #0: (&bdev->bd_mutex){+.+.}, at: [<00000000bd6db821>] __blkdev_get+0xf3/0xf90 fs/block_dev.c:1457 2 locks held by syz-executor.2/1838: #0: (&bdev->bd_mutex){+.+.}, at: [<00000000bd6db821>] __blkdev_get+0xf3/0xf90 fs/block_dev.c:1457 #1: (loop_index_mutex){+.+.}, at: [<000000007b58c0c5>] lo_open+0x19/0xb0 drivers/block/loop.c:1623 1 lock held by syz-executor.3/1840: #0: (&bdev->bd_mutex){+.+.}, at: [<00000000bd6db821>] __blkdev_get+0xf3/0xf90 fs/block_dev.c:1457 1 lock held by syz-executor.1/1841: #0: (&bdev->bd_mutex){+.+.}, at: [<00000000bd6db821>] __blkdev_get+0xf3/0xf90 fs/block_dev.c:1457 2 locks held by syz-executor.0/3565: #0: (&lo->lo_ctl_mutex/1){+.+.}, at: [<000000004f4542e3>] lo_ioctl+0x86/0x1a30 drivers/block/loop.c:1404 #1: (&bdev->bd_mutex){+.+.}, at: [<0000000078c8a81f>] blkdev_reread_part+0x1b/0x40 block/ioctl.c:192 1 lock held by syz-executor.0/3580: #0: (&bdev->bd_mutex){+.+.}, at: [<00000000bd6db821>] __blkdev_get+0xf3/0xf90 fs/block_dev.c:1457 2 locks held by syz-executor.0/3607: #0: (&bdev->bd_mutex){+.+.}, at: [<00000000bd6db821>] __blkdev_get+0xf3/0xf90 fs/block_dev.c:1457 #1: (&bdev->bd_mutex/1){+.+.}, at: [<00000000bd6db821>] __blkdev_get+0xf3/0xf90 fs/block_dev.c:1457 2 locks held by syz-executor.5/3591: #0: (loop_index_mutex){+.+.}, at: [<00000000b4d91c48>] loop_control_ioctl+0x71/0x310 drivers/block/loop.c:1982 #1: (&lo->lo_ctl_mutex#2){+.+.}, at: [<00000000fbd499bf>] loop_control_ioctl+0x183/0x310 drivers/block/loop.c:1996 2 locks held by blkid/3592: #0: (&bdev->bd_mutex){+.+.}, at: [<00000000bd6db821>] __blkdev_get+0xf3/0xf90 fs/block_dev.c:1457 #1: (loop_index_mutex){+.+.}, at: [<000000007b58c0c5>] lo_open+0x19/0xb0 drivers/block/loop.c:1623 2 locks held by blkid/3593: #0: (&bdev->bd_mutex){+.+.}, at: [<00000000bd6db821>] __blkdev_get+0xf3/0xf90 fs/block_dev.c:1457 #1: (loop_index_mutex){+.+.}, at: [<000000007b58c0c5>] lo_open+0x19/0xb0 drivers/block/loop.c:1623 2 locks held by blkid/3594: #0: (&bdev->bd_mutex){+.+.}, at: [<00000000bd6db821>] __blkdev_get+0xf3/0xf90 fs/block_dev.c:1457 #1: (loop_index_mutex){+.+.}, at: [<000000007b58c0c5>] lo_open+0x19/0xb0 drivers/block/loop.c:1623 2 locks held by blkid/3601: #0: (&bdev->bd_mutex){+.+.}, at: [<00000000bd6db821>] __blkdev_get+0xf3/0xf90 fs/block_dev.c:1457 #1: (loop_index_mutex){+.+.}, at: [<000000007b58c0c5>] lo_open+0x19/0xb0 drivers/block/loop.c:1623 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 23 Comm: khungtaskd Not tainted 4.14.140+ #38 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0xca/0x134 lib/dump_stack.c:53 nmi_cpu_backtrace.cold+0x47/0x86 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x119/0x147 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+0x629/0xbe0 kernel/hung_task.c:274 kthread+0x31f/0x430 kernel/kthread.c:232 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:404 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 skipped: idling at pc 0xffffffff8f299063