INFO: task syz-executor4:1935 blocked for more than 140 seconds. Not tainted 4.14.67+ #1 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor4 D27464 1935 1 0x00000004 Call Trace: schedule+0x7f/0x1b0 kernel/sched/core.c:3490 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3548 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x521/0x1480 kernel/locking/mutex.c:893 lo_release+0x1a/0x190 drivers/block/loop.c:1635 __blkdev_put+0x526/0x6e0 fs/block_dev.c:1783 blkdev_close+0x86/0xb0 fs/block_dev.c:1855 __fput+0x25e/0x6f0 fs/file_table.c:210 task_work_run+0x116/0x190 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:191 [inline] exit_to_usermode_loop+0x12e/0x150 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+0x35d/0x4b0 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x410c30 RSP: 002b:00007ffe34028ce8 EFLAGS: 00000246 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000410c30 RDX: 0000000000000000 RSI: 0000000000004c01 RDI: 0000000000000003 RBP: 0000000000000003 R08: 0000000000000000 R09: 000000000000000a R10: 0000000000000075 R11: 0000000000000246 R12: 0000000000000019 R13: 0000000000054376 R14: 00000000000001d7 R15: badc0ffeebadface INFO: task syz-executor1:1941 blocked for more than 140 seconds. Not tainted 4.14.67+ #1 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor1 D27384 1941 1 0x00000004 Call Trace: schedule+0x7f/0x1b0 kernel/sched/core.c:3490 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3548 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x521/0x1480 kernel/locking/mutex.c:893 lo_open+0x17/0xa0 drivers/block/loop.c:1592 __blkdev_get+0x267/0xe50 fs/block_dev.c:1467 blkdev_get+0x97/0x8c0 fs/block_dev.c:1604 blkdev_open+0x1bd/0x240 fs/block_dev.c:1762 do_dentry_open+0x426/0xda0 fs/open.c:764 vfs_open+0x11c/0x210 fs/open.c:878 do_last fs/namei.c:3408 [inline] path_openat+0x4eb/0x23a0 fs/namei.c:3550 do_filp_open+0x197/0x270 fs/namei.c:3584 do_sys_open+0x2ef/0x580 fs/open.c:1071 do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x410db0 RSP: 002b:00007fffd4d73698 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000410db0 RDX: 00007fffd4d736da RSI: 0000000000000002 RDI: 00007fffd4d736d0 RBP: 00000000000004f7 R08: 0000000000000000 R09: 000000000000000a R10: 0000000000000075 R11: 0000000000000246 R12: 0000000000000006 R13: 0000000000054b2f R14: 000000000000011d R15: badc0ffeebadface INFO: task syz-executor3:1944 blocked for more than 140 seconds. Not tainted 4.14.67+ #1 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor3 D27768 1944 1 0x00000004 Call Trace: schedule+0x7f/0x1b0 kernel/sched/core.c:3490 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3548 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x521/0x1480 kernel/locking/mutex.c:893 lo_release+0x1a/0x190 drivers/block/loop.c:1635 __blkdev_put+0x526/0x6e0 fs/block_dev.c:1783 blkdev_close+0x86/0xb0 fs/block_dev.c:1855 __fput+0x25e/0x6f0 fs/file_table.c:210 task_work_run+0x116/0x190 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:191 [inline] exit_to_usermode_loop+0x12e/0x150 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+0x35d/0x4b0 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x410c30 RSP: 002b:00007ffec541bd78 EFLAGS: 00000246 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000410c30 RDX: 0000000000000000 RSI: 0000000000004c01 RDI: 0000000000000003 RBP: 0000000000000003 R08: 0000000000000000 R09: 000000000000000a R10: 0000000000000075 R11: 0000000000000246 R12: 000000000000000a R13: 0000000000054b31 R14: 00000000000001dd R15: badc0ffeebadface INFO: task syz-executor6:1946 blocked for more than 140 seconds. Not tainted 4.14.67+ #1 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor6 D27704 1946 1 0x00000004 Call Trace: schedule+0x7f/0x1b0 kernel/sched/core.c:3490 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3548 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x521/0x1480 kernel/locking/mutex.c:893 lo_open+0x17/0xa0 drivers/block/loop.c:1592 __blkdev_get+0x267/0xe50 fs/block_dev.c:1467 blkdev_get+0x97/0x8c0 fs/block_dev.c:1604 blkdev_open+0x1bd/0x240 fs/block_dev.c:1762 do_dentry_open+0x426/0xda0 fs/open.c:764 vfs_open+0x11c/0x210 fs/open.c:878 do_last fs/namei.c:3408 [inline] path_openat+0x4eb/0x23a0 fs/namei.c:3550 do_filp_open+0x197/0x270 fs/namei.c:3584 do_sys_open+0x2ef/0x580 fs/open.c:1071 do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x410db0 RSP: 002b:00007ffee1b45008 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000410db0 RDX: 00007ffee1b4504a RSI: 0000000000000002 RDI: 00007ffee1b45040 RBP: 00000000000004db R08: 0000000000000000 R09: 000000000000000a R10: 0000000000000075 R11: 0000000000000246 R12: 000000000000000c R13: 0000000000054b2d R14: 0000000000000111 R15: badc0ffeebadface INFO: task syz-executor7:16401 blocked for more than 140 seconds. Not tainted 4.14.67+ #1 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor7 D27144 16401 16365 0x00000000 Call Trace: schedule+0x7f/0x1b0 kernel/sched/core.c:3490 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3548 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x521/0x1480 kernel/locking/mutex.c:893 lo_open+0x17/0xa0 drivers/block/loop.c:1592 __blkdev_get+0x267/0xe50 fs/block_dev.c:1467 blkdev_get+0x97/0x8c0 fs/block_dev.c:1604 blkdev_open+0x1bd/0x240 fs/block_dev.c:1762 do_dentry_open+0x426/0xda0 fs/open.c:764 vfs_open+0x11c/0x210 fs/open.c:878 do_last fs/namei.c:3408 [inline] path_openat+0x4eb/0x23a0 fs/namei.c:3550 do_filp_open+0x197/0x270 fs/namei.c:3584 do_sys_open+0x2ef/0x580 fs/open.c:1071 do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x410db0 RSP: 002b:00007ffd8c537628 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000410db0 RDX: 00007ffd8c53766a RSI: 0000000000000002 RDI: 00007ffd8c537660 RBP: 0000000000000360 R08: 0000000000000000 R09: 000000000000000a R10: 0000000000000075 R11: 0000000000000246 R12: 000000000000000a R13: 0000000000054b2f R14: 00000000000000b1 R15: badc0ffeebadface INFO: task syz-executor0:23048 blocked for more than 140 seconds. Not tainted 4.14.67+ #1 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor0 D28968 23048 1940 0x00000004 Call Trace: schedule+0x7f/0x1b0 kernel/sched/core.c:3490 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3548 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x521/0x1480 kernel/locking/mutex.c:893 blkdev_reread_part+0x18/0x30 block/ioctl.c:192 loop_reread_partitions+0x72/0x80 drivers/block/loop.c:614 loop_set_status+0xa84/0xf40 drivers/block/loop.c:1169 loop_set_status64+0x8d/0xe0 drivers/block/loop.c:1287 lo_ioctl+0x3cd/0x17d0 drivers/block/loop.c:1400 __blkdev_driver_ioctl block/ioctl.c:297 [inline] blkdev_ioctl+0x57d/0x18c0 block/ioctl.c:594 block_ioctl+0xd9/0x120 fs/block_dev.c:1873 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0x1a0/0x1030 fs/ioctl.c:684 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x7e/0xb0 fs/ioctl.c:692 do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x456f07 RSP: 002b:00007f299867da18 EFLAGS: 00000202 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f299867e6d4 RCX: 0000000000456f07 RDX: 00007f299867dab0 RSI: 0000000000004c04 RDI: 0000000000000004 RBP: 0000000000000000 R08: 0000000000000000 R09: 000000000000000a R10: 0000000000000075 R11: 0000000000000202 R12: 0000000000000000 R13: 0000000000000003 R14: 0000000000000004 R15: 0000000000000000 INFO: task syz-executor0:23062 blocked for more than 140 seconds. Not tainted 4.14.67+ #1 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor0 D28472 23062 1940 0x00000004 Call Trace: schedule+0x7f/0x1b0 kernel/sched/core.c:3490 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3548 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x521/0x1480 kernel/locking/mutex.c:893 __blkdev_get+0xf3/0xe50 fs/block_dev.c:1452 blkdev_get+0x97/0x8c0 fs/block_dev.c:1604 blkdev_open+0x1bd/0x240 fs/block_dev.c:1762 do_dentry_open+0x426/0xda0 fs/open.c:764 vfs_open+0x11c/0x210 fs/open.c:878 do_last fs/namei.c:3408 [inline] path_openat+0x4eb/0x23a0 fs/namei.c:3550 do_filp_open+0x197/0x270 fs/namei.c:3584 do_sys_open+0x2ef/0x580 fs/open.c:1071 do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x410dd1 RSP: 002b:00007f299865ca10 EFLAGS: 00000293 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 00007f299865d6d4 RCX: 0000000000410dd1 RDX: 00007f299865cbaa RSI: 0000000000000002 RDI: 00007f299865cba0 RBP: 0000000000000000 R08: 0000000000000000 R09: 000000000000000a R10: 0000000000000075 R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000007 R14: 0000000000000007 R15: 0000000000000001 INFO: task syz-executor5:23056 blocked for more than 140 seconds. Not tainted 4.14.67+ #1 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor5 D28824 23056 1942 0x00000004 Call Trace: schedule+0x7f/0x1b0 kernel/sched/core.c:3490 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3548 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x521/0x1480 kernel/locking/mutex.c:893 loop_control_ioctl+0x180/0x310 drivers/block/loop.c:1965 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0x1a0/0x1030 fs/ioctl.c:684 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x7e/0xb0 fs/ioctl.c:692 do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x457099 RSP: 002b:00007f024c1d6c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f024c1d76d4 RCX: 0000000000457099 RDX: 0000000000000000 RSI: 0000000000004c81 RDI: 0000000000000005 RBP: 00000000009300a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000004cf8c8 R14: 00000000004c5b29 R15: 0000000000000000 INFO: task syz-executor5:23067 blocked for more than 140 seconds. Not tainted 4.14.67+ #1 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor5 D29016 23067 1942 0x00000004 Call Trace: schedule+0x7f/0x1b0 kernel/sched/core.c:3490 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3548 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x521/0x1480 kernel/locking/mutex.c:893 loop_control_ioctl+0x71/0x310 drivers/block/loop.c:1951 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0x1a0/0x1030 fs/ioctl.c:684 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x7e/0xb0 fs/ioctl.c:692 do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x457099 RSP: 002b:00007f024c1b5c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f024c1b66d4 RCX: 0000000000457099 RDX: 0000000000000000 RSI: 0000000000004c80 RDI: 0000000000000005 RBP: 0000000000930140 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000004cf898 R14: 00000000004c5afe R15: 0000000000000001 INFO: task syz-executor5:23069 blocked for more than 140 seconds. Not tainted 4.14.67+ #1 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor5 D29768 23069 1942 0x00000004 Call Trace: schedule+0x7f/0x1b0 kernel/sched/core.c:3490 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3548 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x521/0x1480 kernel/locking/mutex.c:893 loop_control_ioctl+0x71/0x310 drivers/block/loop.c:1951 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0x1a0/0x1030 fs/ioctl.c:684 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x7e/0xb0 fs/ioctl.c:692 do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x457099 RSP: 002b:00007f024c194c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f024c1956d4 RCX: 0000000000457099 RDX: 00000000200001c0 RSI: 000000000000540f RDI: 0000000000000005 RBP: 00000000009301e0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000004d0c48 R14: 00000000004c6593 R15: 0000000000000002 Showing all locks held in the system: 1 lock held by khungtaskd/23: #0: (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0x74/0x20f kernel/locking/lockdep.c:4541 2 locks held by getty/1851: #0: (&tty->ldisc_sem){++++}, at: [] tty_ldisc_ref_wait+0x20/0x80 drivers/tty/tty_ldisc.c:275 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1ff/0x15e0 drivers/tty/n_tty.c:2142 2 locks held by syz-executor4/1935: #0: (&bdev->bd_mutex){+.+.}, at: [] __blkdev_put+0xb1/0x6e0 fs/block_dev.c:1770 #1: (loop_index_mutex){+.+.}, at: [] lo_release+0x1a/0x190 drivers/block/loop.c:1635 2 locks held by syz-executor1/1941: #0: (&bdev->bd_mutex){+.+.}, at: [] __blkdev_get+0xf3/0xe50 fs/block_dev.c:1452 #1: (loop_index_mutex){+.+.}, at: [] lo_open+0x17/0xa0 drivers/block/loop.c:1592 2 locks held by syz-executor3/1944: #0: (&bdev->bd_mutex){+.+.}, at: [] __blkdev_put+0xb1/0x6e0 fs/block_dev.c:1770 #1: (loop_index_mutex){+.+.}, at: [] lo_release+0x1a/0x190 drivers/block/loop.c:1635 2 locks held by syz-executor6/1946: #0: (&bdev->bd_mutex){+.+.}, at: [] __blkdev_get+0xf3/0xe50 fs/block_dev.c:1452 #1: (loop_index_mutex){+.+.}, at: [] lo_open+0x17/0xa0 drivers/block/loop.c:1592 2 locks held by syz-executor7/16401: #0: (&bdev->bd_mutex){+.+.}, at: [] __blkdev_get+0xf3/0xe50 fs/block_dev.c:1452 #1: (loop_index_mutex){+.+.}, at: [] lo_open+0x17/0xa0 drivers/block/loop.c:1592 2 locks held by syz-executor0/23048: #0: (&lo->lo_ctl_mutex/1){+.+.}, at: [] lo_ioctl+0x85/0x17d0 drivers/block/loop.c:1373 #1: (&bdev->bd_mutex){+.+.}, at: [] blkdev_reread_part+0x18/0x30 block/ioctl.c:192 1 lock held by syz-executor0/23062: #0: (&bdev->bd_mutex){+.+.}, at: [] __blkdev_get+0xf3/0xe50 fs/block_dev.c:1452 2 locks held by syz-executor5/23056: #0: (loop_index_mutex){+.+.}, at: [] loop_control_ioctl+0x71/0x310 drivers/block/loop.c:1951 #1: (&lo->lo_ctl_mutex#2){+.+.}, at: [] loop_control_ioctl+0x180/0x310 drivers/block/loop.c:1965 1 lock held by syz-executor5/23067: #0: (loop_index_mutex){+.+.}, at: [] loop_control_ioctl+0x71/0x310 drivers/block/loop.c:1951 1 lock held by syz-executor5/23069: #0: (loop_index_mutex){+.+.}, at: [] loop_control_ioctl+0x71/0x310 drivers/block/loop.c:1951 1 lock held by syz-executor5/23088: #0: (loop_index_mutex){+.+.}, at: [] loop_control_ioctl+0x71/0x310 drivers/block/loop.c:1951 1 lock held by syz-executor5/23091: #0: (loop_index_mutex){+.+.}, at: [] loop_control_ioctl+0x71/0x310 drivers/block/loop.c:1951 1 lock held by syz-executor5/23092: #0: (loop_index_mutex){+.+.}, at: [] loop_control_ioctl+0x71/0x310 drivers/block/loop.c:1951 1 lock held by blkid/23058: #0: (&bdev->bd_mutex){+.+.}, at: [] __blkdev_get+0xf3/0xe50 fs/block_dev.c:1452 2 locks held by blkid/23059: #0: (&bdev->bd_mutex){+.+.}, at: [] __blkdev_get+0xf3/0xe50 fs/block_dev.c:1452 #1: (loop_index_mutex){+.+.}, at: [] lo_open+0x17/0xa0 drivers/block/loop.c:1592 1 lock held by blkid/23063: #0: (&bdev->bd_mutex){+.+.}, at: [] __blkdev_get+0xf3/0xe50 fs/block_dev.c:1452 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 23 Comm: khungtaskd Not tainted 4.14.67+ #1 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0xb9/0x11b lib/dump_stack.c:53 nmi_cpu_backtrace.cold.0+0x18/0x8e lib/nmi_backtrace.c:103 nmi_trigger_cpumask_backtrace+0x121/0x146 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:138 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:196 [inline] watchdog+0x574/0xa70 kernel/hung_task.c:252 kthread+0x348/0x420 kernel/kthread.c:232 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:402 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 skipped: idling at pc 0xffffffffbb640572