INFO: task syz-executor.1:1838 blocked for more than 140 seconds. Not tainted 4.14.114+ #63 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D25080 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+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.0:9519 blocked for more than 140 seconds. Not tainted 4.14.114+ #63 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D29248 9519 1829 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:9521 blocked for more than 140 seconds. Not tainted 4.14.114+ #63 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. blkid D28792 9521 2796 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:9523 blocked for more than 140 seconds. Not tainted 4.14.114+ #63 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. blkid D29248 9523 313 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 blkid:9524 blocked for more than 140 seconds. Not tainted 4.14.114+ #63 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. blkid D27216 9524 310 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 blkid:9525 blocked for more than 140 seconds. Not tainted 4.14.114+ #63 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. blkid D29136 9525 2900 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: [<0000000077a0216d>] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4541 2 locks held by getty/1746: #0: (&tty->ldisc_sem){++++}, at: [<000000001888fd54>] tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:284 #1: (&ldata->atomic_read_lock){+.+.}, at: [<0000000042f5dd67>] n_tty_read+0x1f7/0x1700 drivers/tty/n_tty.c:2156 3 locks held by syz-executor.1/1838: #0: (&bdev->bd_mutex){+.+.}, at: [<000000005a1f0016>] __blkdev_put+0xb1/0x6d0 fs/block_dev.c:1778 #1: (loop_index_mutex){+.+.}, at: [<00000000277d8f94>] lo_release+0x19/0x190 drivers/block/loop.c:1667 #2: (loop_ctl_mutex#2){+.+.}, at: [<000000009081f67e>] __lo_release drivers/block/loop.c:1644 [inline] #2: (loop_ctl_mutex#2){+.+.}, at: [<000000009081f67e>] lo_release+0x78/0x190 drivers/block/loop.c:1668 2 locks held by syz-executor.0/9519: #0: (loop_ctl_mutex/1){+.+.}, at: [<0000000092a1a924>] lo_ioctl+0x83/0x1970 drivers/block/loop.c:1405 #1: (&bdev->bd_mutex){+.+.}, at: [<00000000342f593c>] blkdev_reread_part+0x1b/0x40 block/ioctl.c:192 1 lock held by blkid/9521: #0: (&bdev->bd_mutex){+.+.}, at: [<00000000686a9de1>] __blkdev_get+0xf3/0xf90 fs/block_dev.c:1457 2 locks held by blkid/9523: #0: (&bdev->bd_mutex){+.+.}, at: [<00000000686a9de1>] __blkdev_get+0xf3/0xf90 fs/block_dev.c:1457 #1: (loop_index_mutex){+.+.}, at: [<000000004f6fe736>] lo_open+0x19/0xb0 drivers/block/loop.c:1624 2 locks held by blkid/9524: #0: (&bdev->bd_mutex){+.+.}, at: [<00000000686a9de1>] __blkdev_get+0xf3/0xf90 fs/block_dev.c:1457 #1: (loop_index_mutex){+.+.}, at: [<000000004f6fe736>] lo_open+0x19/0xb0 drivers/block/loop.c:1624 2 locks held by blkid/9525: #0: (&bdev->bd_mutex){+.+.}, at: [<00000000686a9de1>] __blkdev_get+0xf3/0xf90 fs/block_dev.c:1457 #1: (loop_index_mutex){+.+.}, at: [<000000004f6fe736>] lo_open+0x19/0xb0 drivers/block/loop.c:1624 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 23 Comm: khungtaskd Not tainted 4.14.114+ #63 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: 4774 Comm: syz-executor.2 Not tainted 4.14.114+ #63 task: 00000000d46b04c0 task.stack: 00000000bc1a300e RIP: 0010:entry_SYSCALL_64_after_hwframe+0x3a/0xb7 RSP: 0018:ffff88819e977f58 EFLAGS: 00000046 RAX: 00000000ffffc0cd RBX: 0000000000000000 RCX: 0000000020000111 RDX: c8c5bc1a088b69da RSI: 0000000000000000 RDI: 00007f71de894608 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 00007f71de8a4700(0000) GS:ffff8881d7700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fe2e72e4000 CR3: 00000001c41f0001 CR4: 00000000001606a0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: RIP: 0033:0x20000111 RSP: 002b:00007f71de8a3bd8 EFLAGS: 00000a12 ORIG_RAX: 00000000ffffc0cd RAX: ffffffffffffffda RBX: 00000000c021bf45 RCX: 0000000020000111 RDX: c8c5bc1a088b69da RSI: 0000000000000000 RDI: 00007f71de894608 RBP: 0000000060437e77 R08: 0000000000000005 R09: 0000000000000006 R10: 0000000000000007 R11: 0000000000000a12 R12: 000000000000000b R13: 000000000000000c R14: 000000000000000d R15: 00000000ffffffff Code: 31 c9 41 52 45 31 d2 41 53 45 31 db 53 31 db 55 31 ed 41 54 45 31 e4 41 55 45 31 ed 41 56 45 31 f6 41 57 45 31 ff e8 0c 20 60 fe <48> 89 e7 e8 ca 4e 60 fe 0f ba a4 24 90 00 00 00 09 73 05 e8 d8