INFO: task syz-executor.0:17926 blocked for more than 140 seconds. Not tainted 4.14.111+ #54 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D29192 17926 16352 0x80000002 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_put+0x27/0x4c0 fs/block_dev.c:1814 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 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0x903/0x2960 kernel/exit.c:874 INFO: task syz-executor.0:8784 blocked for more than 140 seconds. Not tainted 4.14.111+ #54 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D28344 8784 16352 0x80000002 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+0x19/0x190 drivers/block/loop.c:1667 __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 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0x903/0x2960 kernel/exit.c:874 INFO: task syz-executor.3:14195 blocked for more than 140 seconds. Not tainted 4.14.111+ #54 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.3 D25640 14195 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.4:16811 blocked for more than 140 seconds. Not tainted 4.14.111+ #54 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D25640 16811 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.5:18364 blocked for more than 140 seconds. Not tainted 4.14.111+ #54 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D28896 18364 1863 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_clr_fd+0x828/0xac0 drivers/block/loop.c:1069 lo_ioctl+0x813/0x1970 drivers/block/loop.c:1415 __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.0:18343 blocked for more than 140 seconds. Not tainted 4.14.111+ #54 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D29024 18343 16352 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+0x19/0x190 drivers/block/loop.c:1667 __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 blkid:18368 blocked for more than 140 seconds. Not tainted 4.14.111+ #54 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. blkid D28496 18368 11169 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 INFO: task blkid:18372 blocked for more than 140 seconds. Not tainted 4.14.111+ #54 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. blkid D29120 18372 11170 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 Showing all locks held in the system: 1 lock held by khungtaskd/23: #0: (tasklist_lock){.+.+}, at: [<000000000409d31a>] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4544 2 locks held by getty/1767: #0: (&tty->ldisc_sem){++++}, at: [<00000000752b9a8f>] tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:275 #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000508a9f9d>] n_tty_read+0x1f7/0x1700 drivers/tty/n_tty.c:2156 1 lock held by syz-executor.0/17926: #0: (&bdev->bd_mutex){+.+.}, at: [<00000000d8c66f17>] blkdev_put+0x27/0x4c0 fs/block_dev.c:1814 2 locks held by syz-executor.0/8784: #0: (&bdev->bd_mutex){+.+.}, at: [<000000007db4d664>] __blkdev_put+0xb1/0x6d0 fs/block_dev.c:1778 #1: (loop_index_mutex){+.+.}, at: [<000000007f0079d2>] lo_release+0x19/0x190 drivers/block/loop.c:1667 2 locks held by syz-executor.3/14195: #0: (&bdev->bd_mutex){+.+.}, at: [<00000000122c2bdb>] __blkdev_get+0xf3/0xf90 fs/block_dev.c:1457 #1: (loop_index_mutex){+.+.}, at: [<00000000607db166>] lo_open+0x19/0xb0 drivers/block/loop.c:1624 3 locks held by syz-executor.4/16811: #0: (&bdev->bd_mutex){+.+.}, at: [<000000007db4d664>] __blkdev_put+0xb1/0x6d0 fs/block_dev.c:1778 #1: (loop_index_mutex){+.+.}, at: [<000000007f0079d2>] lo_release+0x19/0x190 drivers/block/loop.c:1667 #2: (loop_ctl_mutex#2){+.+.}, at: [<00000000adbfe4d2>] __lo_release drivers/block/loop.c:1644 [inline] #2: (loop_ctl_mutex#2){+.+.}, at: [<00000000adbfe4d2>] lo_release+0x78/0x190 drivers/block/loop.c:1668 2 locks held by syz-executor.5/18364: #0: (loop_ctl_mutex/1){+.+.}, at: [<0000000033dcb315>] lo_ioctl+0x83/0x1970 drivers/block/loop.c:1405 #1: (&bdev->bd_mutex){+.+.}, at: [<00000000b5c29cb1>] blkdev_reread_part+0x1b/0x40 block/ioctl.c:192 2 locks held by syz-executor.0/18343: #0: (&bdev->bd_mutex){+.+.}, at: [<000000007db4d664>] __blkdev_put+0xb1/0x6d0 fs/block_dev.c:1778 #1: (loop_index_mutex){+.+.}, at: [<000000007f0079d2>] lo_release+0x19/0x190 drivers/block/loop.c:1667 2 locks held by blkid/18368: #0: (&bdev->bd_mutex){+.+.}, at: [<00000000122c2bdb>] __blkdev_get+0xf3/0xf90 fs/block_dev.c:1457 #1: (loop_index_mutex){+.+.}, at: [<00000000607db166>] lo_open+0x19/0xb0 drivers/block/loop.c:1624 1 lock held by blkid/18372: #0: (&bdev->bd_mutex){+.+.}, at: [<00000000122c2bdb>] __blkdev_get+0xf3/0xf90 fs/block_dev.c:1457 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 23 Comm: khungtaskd Not tainted 4.14.111+ #54 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: 18395 Comm: init Not tainted 4.14.111+ #54 task: 00000000af3c25e8 task.stack: 0000000059416862 RIP: 0010:lookup_chain_cache kernel/locking/lockdep.c:2358 [inline] RIP: 0010:lookup_chain_cache_add kernel/locking/lockdep.c:2377 [inline] RIP: 0010:validate_chain kernel/locking/lockdep.c:2431 [inline] RIP: 0010:__lock_acquire+0xbbb/0x3fa0 kernel/locking/lockdep.c:3487 RSP: 0018:ffff8881a3c57c60 EFLAGS: 00000806 RAX: 1ffffffff2adf5a3 RBX: ffffffff956fad00 RCX: 000000000eae4bec RDX: 1ffffffff2ba18dc RSI: ffff8881d3113730 RDI: ffffffff956fad18 RBP: ffff8881a3c57e18 R08: 00000000000017d0 R09: 0000000000040094 R10: ffff8881d3113730 R11: 0000000000000001 R12: ffff8881d3113748 R13: dffffc0000000000 R14: 1c13cc133a5445dd R15: ffff8881d3112f00 FS: 00007f606176d7a0(0000) GS:ffff8881dbb00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f6060e49330 CR3: 00000001a278e001 CR4: 00000000001606a0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 Call Trace: Code: 08 d0 95 48 85 db 74 57 48 83 eb 08 74 51 49 bd 00 00 00 00 00 fc ff df eb 06 48 83 eb 08 74 3f 48 8d 7b 18 48 89 f8 48 c1 e8 03 <42> 80 3c 28 00 0f 85 26 1f 00 00 4c 3b 73 18 0f 84 ba fb ff ff