INFO: task syz-executor1:1842 blocked for more than 140 seconds. Not tainted 4.14.78+ #22 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor1 D26680 1842 1 0x10000004 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_probe+0x71/0x180 drivers/block/loop.c:1931 kobj_lookup+0x230/0x420 drivers/base/map.c:124 get_gendisk+0x32/0x230 block/genhd.c:785 __blkdev_get+0x345/0xe50 fs/block_dev.c:1446 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: 0033:0x411180 RSP: 002b:00007ffc5f5502f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000411180 RDX: 00007ffc5f55036a RSI: 0000000000000002 RDI: 00007ffc5f550360 RBP: 000000000000041a R08: 0000000000000000 R09: 000000000000000a R10: 0000000000000075 R11: 0000000000000246 R12: 0000000000000007 R13: 0000000000044787 R14: 00000000000000d8 R15: 0000000000000001 INFO: task syz-executor0:12621 blocked for more than 140 seconds. Not tainted 4.14.78+ #22 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor0 D27144 12621 1 0x10000004 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+0x8e2/0xe50 fs/block_dev.c:1529 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: 0033:0x411180 RSP: 002b:00007ffeae2237b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000411180 RDX: 00007ffeae22382a RSI: 0000000000000002 RDI: 00007ffeae223820 RBP: 000000000000014e R08: 0000000000000000 R09: 000000000000000a R10: 0000000000000075 R11: 0000000000000246 R12: 000000000000000a R13: 00000000000445b9 R14: 0000000000000016 R15: 0000000000000000 INFO: task syz-executor3:13780 blocked for more than 140 seconds. Not tainted 4.14.78+ #22 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor3 D26552 13780 12101 0x10000004 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: 0033:0x457569 RSP: 002b:00007fa316767c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 0000000000457569 RDX: 0000000000000000 RSI: 0000000000004c82 RDI: 0000000000000005 RBP: 000000000072bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fa3167686d4 R13: 00000000004c03b2 R14: 00000000004d0558 R15: 00000000ffffffff INFO: task syz-executor3:13793 blocked for more than 140 seconds. Not tainted 4.14.78+ #22 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor3 D28936 13793 12101 0x10000004 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: 0033:0x4573d7 RSP: 002b:00007fa316746a18 EFLAGS: 00000202 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fa3167476d4 RCX: 00000000004573d7 RDX: 00007fa316746ab0 RSI: 0000000000004c04 RDI: 0000000000000008 RBP: 0000000000000005 R08: 0000000000000000 R09: 000000000000000a R10: 0000000000000075 R11: 0000000000000202 R12: 00007fa3167476d4 R13: 0000000000000007 R14: 0000000000000008 R15: 0000000000000005 INFO: task syz-executor3:13803 blocked for more than 140 seconds. Not tainted 4.14.78+ #22 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor3 D29768 13803 12101 0x10000004 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: 0033:0x457569 RSP: 002b:00007fa316725c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457569 RDX: 0000000000000003 RSI: 0000000000004c81 RDI: 0000000000000005 RBP: 000000000072c040 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fa3167266d4 R13: 00000000004c03ca R14: 00000000004d0570 R15: 00000000ffffffff INFO: task syz-executor3:13812 blocked for more than 140 seconds. Not tainted 4.14.78+ #22 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor3 D29672 13812 12101 0x10000004 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: 0033:0x457569 RSP: 002b:00007fa316704c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457569 RDX: 0000000000000003 RSI: 0000000000004c81 RDI: 0000000000000005 RBP: 000000000072c0e0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fa3167056d4 R13: 00000000004c03ca R14: 00000000004d0570 R15: 00000000ffffffff INFO: task blkid:13806 blocked for more than 140 seconds. Not tainted 4.14.78+ #22 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. blkid D28840 13806 5664 0x10000004 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+0x8e2/0xe50 fs/block_dev.c:1529 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: 0033:0x7f81f1ea9120 RSP: 002b:00007ffd740f9148 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f81f1ea9120 RDX: 00007ffd740f9f41 RSI: 0000000000000000 RDI: 00007ffd740f9f41 RBP: 0000000000000000 R08: 0000000000000078 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000dbe030 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000005 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/1754: #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 1 lock held by syz-executor1/1842: #0: (loop_index_mutex){+.+.}, at: [] loop_probe+0x71/0x180 drivers/block/loop.c:1931 2 locks held by syz-executor0/12621: #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 syz-executor3/13780: #0: (loop_index_mutex){+.+.}, at: [] loop_control_ioctl+0x71/0x310 drivers/block/loop.c:1951 2 locks held by syz-executor3/13793: #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 2 locks held by syz-executor3/13803: #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-executor3/13812: #0: (loop_index_mutex){+.+.}, at: [] loop_control_ioctl+0x71/0x310 drivers/block/loop.c:1951 2 locks held by blkid/13806: #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 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 23 Comm: khungtaskd Not tainted 4.14.78+ #22 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0xb9/0x11b lib/dump_stack.c:53 nmi_cpu_backtrace.cold.0+0x47/0x85 lib/nmi_backtrace.c:101 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 1 to CPUs 0: NMI backtrace for cpu 0 skipped: idling at pc 0xffffffff88656702