INFO: task syz-executor.0:4639 blocked for more than 140 seconds. Not tainted 4.14.146+ #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D25312 4639 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:3539 [inline] path_openat+0xb6c/0x2be0 fs/namei.c:3681 do_filp_open+0x1a1/0x280 fs/namei.c:3715 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: 0033:0x4138d0 RSP: 002b:00007ffdb08563b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 0000000000064440 RCX: 00000000004138d0 RDX: 00007ffdb085644a RSI: 0000000000000002 RDI: 00007ffdb0856440 RBP: 000000000000063b R08: 0000000000000000 R09: 000000000000000a R10: 0000000000000075 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffdb08563f0 R14: 0000000000064311 R15: 00007ffdb0856400 INFO: task syz-executor.3:10804 blocked for more than 140 seconds. Not tainted 4.14.146+ #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.3 D25312 10804 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:3539 [inline] path_openat+0xb6c/0x2be0 fs/namei.c:3681 do_filp_open+0x1a1/0x280 fs/namei.c:3715 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: 0033:0x4138d0 RSP: 002b:00007ffcd30cfcd8 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 0000000000064472 RCX: 00000000004138d0 RDX: 00007ffcd30cfd6a RSI: 0000000000000002 RDI: 00007ffcd30cfd60 RBP: 00000000000004c2 R08: 0000000000000000 R09: 000000000000000a R10: 0000000000000075 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffcd30cfd10 R14: 000000000006431f R15: 00007ffcd30cfd20 INFO: task syz-executor.1:11842 blocked for more than 140 seconds. Not tainted 4.14.146+ #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D25312 11842 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:3539 [inline] path_openat+0xb6c/0x2be0 fs/namei.c:3681 do_filp_open+0x1a1/0x280 fs/namei.c:3715 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: 0033:0x4138d0 RSP: 002b:00007fff2f9e0ea8 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 000000000006439c RCX: 00000000004138d0 RDX: 00007fff2f9e0f3a RSI: 0000000000000002 RDI: 00007fff2f9e0f30 RBP: 0000000000000432 R08: 0000000000000000 R09: 000000000000000a R10: 0000000000000075 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fff2f9e0ee0 R14: 0000000000064372 R15: 00007fff2f9e0ef0 INFO: task syz-executor.5:22814 blocked for more than 140 seconds. Not tainted 4.14.146+ #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D27952 22814 21975 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: 0033:0x459a09 RSP: 002b:00007f8f4a624c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459a09 RDX: 0000000000000000 RSI: 0000000000004c81 RDI: 0000000000000007 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f8f4a6256d4 R13: 00000000004c3143 R14: 00000000004d6a28 R15: 00000000ffffffff INFO: task syz-executor.5:22826 blocked for more than 140 seconds. Not tainted 4.14.146+ #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D29232 22826 21975 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+0x71/0x310 drivers/block/loop.c:1982 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: 0033:0x459a09 RSP: 002b:00007f8f4a603c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459a09 RDX: 0000000000000000 RSI: 0000000000004c81 RDI: 0000000000000006 RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f8f4a6046d4 R13: 00000000004c3143 R14: 00000000004d6a28 R15: 00000000ffffffff INFO: task syz-executor.4:22821 blocked for more than 140 seconds. Not tainted 4.14.146+ #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D29552 22821 9398 0x00000006 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_change_fd drivers/block/loop.c:704 [inline] lo_ioctl+0x14f9/0x1a30 drivers/block/loop.c:1410 __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: 0033:0x459a09 RSP: 002b:00007fb7bf43cc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459a09 RDX: 0000000000000004 RSI: 0000000000004c06 RDI: 0000000000000003 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fb7bf43d6d4 R13: 00000000004c30f1 R14: 00000000004d69c8 R15: 00000000ffffffff INFO: task syz-executor.4:22824 blocked for more than 140 seconds. Not tainted 4.14.146+ #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D29152 22824 9398 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:3539 [inline] path_openat+0xb6c/0x2be0 fs/namei.c:3681 do_filp_open+0x1a1/0x280 fs/namei.c:3715 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: 0033:0x4138f1 RSP: 002b:00007fb7bf41b7a0 EFLAGS: 00000293 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 6666666666666667 RCX: 00000000004138f1 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00007fb7bf41b850 RBP: 000000000075bfc8 R08: 000000000000000f R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 00007fb7bf41c6d4 R13: 00000000004c8e37 R14: 00000000004dff68 R15: 00000000ffffffff INFO: task syz-executor.2:22822 blocked for more than 140 seconds. Not tainted 4.14.146+ #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D29248 22822 11836 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+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/0xe20 fs/open.c:789 vfs_open+0x105/0x230 fs/open.c:903 do_last fs/namei.c:3539 [inline] path_openat+0xb6c/0x2be0 fs/namei.c:3681 do_filp_open+0x1a1/0x280 fs/namei.c:3715 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: 0033:0x4138f1 RSP: 002b:00007f35c7fb37a0 EFLAGS: 00000293 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 6666666666666667 RCX: 00000000004138f1 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00007f35c7fb3850 RBP: 000000000075bf20 R08: 000000000000000f R09: 0000000000000000 R10: 00007f35c7fb49d0 R11: 0000000000000293 R12: 00007f35c7fb46d4 R13: 00000000004c8e37 R14: 00000000004dff68 R15: 00000000ffffffff Showing all locks held in the system: 1 lock held by khungtaskd/23: #0: (tasklist_lock){.+.+}, at: [<00000000a58ea003>] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4541 2 locks held by getty/1758: #0: (&tty->ldisc_sem){++++}, at: [<000000002b34b9e4>] tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:284 #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000cd6d9cae>] n_tty_read+0x1f7/0x1700 drivers/tty/n_tty.c:2156 1 lock held by syz-executor.0/4639: #0: (&bdev->bd_mutex){+.+.}, at: [<000000004e0631b8>] __blkdev_get+0xf3/0xf90 fs/block_dev.c:1457 2 locks held by syz-executor.3/10804: #0: (&bdev->bd_mutex){+.+.}, at: [<000000004e0631b8>] __blkdev_get+0xf3/0xf90 fs/block_dev.c:1457 #1: (loop_index_mutex){+.+.}, at: [<0000000090f23534>] lo_open+0x19/0xb0 drivers/block/loop.c:1623 2 locks held by syz-executor.1/11842: #0: (&bdev->bd_mutex){+.+.}, at: [<000000004e0631b8>] __blkdev_get+0xf3/0xf90 fs/block_dev.c:1457 #1: (loop_index_mutex){+.+.}, at: [<0000000090f23534>] lo_open+0x19/0xb0 drivers/block/loop.c:1623 2 locks held by syz-executor.5/22814: #0: (loop_index_mutex){+.+.}, at: [<000000008a122fc6>] loop_control_ioctl+0x71/0x310 drivers/block/loop.c:1982 #1: (&lo->lo_ctl_mutex#2){+.+.}, at: [<00000000fa4b46ee>] loop_control_ioctl+0x183/0x310 drivers/block/loop.c:1996 1 lock held by syz-executor.5/22826: #0: (loop_index_mutex){+.+.}, at: [<000000008a122fc6>] loop_control_ioctl+0x71/0x310 drivers/block/loop.c:1982 2 locks held by syz-executor.4/22821: #0: (&lo->lo_ctl_mutex/1){+.+.}, at: [<00000000fd03b928>] lo_ioctl+0x86/0x1a30 drivers/block/loop.c:1404 #1: (&bdev->bd_mutex){+.+.}, at: [<0000000061b66762>] blkdev_reread_part+0x1b/0x40 block/ioctl.c:192 1 lock held by syz-executor.4/22824: #0: (&bdev->bd_mutex){+.+.}, at: [<000000004e0631b8>] __blkdev_get+0xf3/0xf90 fs/block_dev.c:1457 2 locks held by syz-executor.2/22822: #0: (&bdev->bd_mutex){+.+.}, at: [<000000004e0631b8>] __blkdev_get+0xf3/0xf90 fs/block_dev.c:1457 #1: (loop_index_mutex){+.+.}, at: [<0000000090f23534>] lo_open+0x19/0xb0 drivers/block/loop.c:1623 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 23 Comm: khungtaskd Not tainted 4.14.146+ #0 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 CPU: 1 PID: 1628 Comm: rs:main Q:Reg Not tainted 4.14.146+ #0 task: 0000000090d98163 task.stack: 000000003963328b RIP: 0010:__sanitizer_cov_trace_pc+0x28/0x60 kernel/kcov.c:93 RSP: 0018:ffff8881d4927550 EFLAGS: 00000297 RAX: ffff8881d56e1780 RBX: ffff8881d70a8ac0 RCX: ffff8881d49275f8 RDX: 0000000000000000 RSI: ffff8881a3bfc700 RDI: ffff8881d70a8aa8 RBP: 1ffff1103a924eb7 R08: 0000000000000001 R09: 0000000000000003 R10: fffffbfff4bc5b9d R11: ffffffffa5e2dceb R12: ffff8881d70a8aa8 R13: ffff8881a3bfc700 R14: ffff8881a3bfc700 R15: 0000000000000000 FS: 00007fcc3bfed700(0000) GS:ffff8881dbb00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007faa6afe1000 CR3: 00000001d1cf4004 CR4: 00000000001606a0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 Call Trace: __blk_mq_sched_bio_merge+0x1e/0x770 block/blk-mq-sched.c:229 blk_mq_sched_bio_merge block/blk-mq-sched.h:44 [inline] blk_mq_make_request+0x1ee/0x19c0 block/blk-mq.c:1662 generic_make_request block/blk-core.c:2227 [inline] generic_make_request+0x212/0x880 block/blk-core.c:2171 submit_bio+0xa7/0x390 block/blk-core.c:2301 submit_bh_wbc.isra.0+0x45c/0x600 fs/buffer.c:3152 submit_bh fs/buffer.c:3158 [inline] __sync_dirty_buffer+0xda/0x1e0 fs/buffer.c:3244 ext4_write_inode+0x3bd/0x450 fs/ext4/inode.c:5309 write_inode fs/fs-writeback.c:1224 [inline] __writeback_single_inode+0x87c/0x10a0 fs/fs-writeback.c:1423 writeback_single_inode+0x1ff/0x370 fs/fs-writeback.c:1477 sync_inode fs/fs-writeback.c:2505 [inline] sync_inode_metadata+0xb8/0xf0 fs/fs-writeback.c:2525 __generic_file_fsync+0x121/0x190 fs/libfs.c:988 ext4_sync_file+0x3ac/0x1250 fs/ext4/fsync.c:120 vfs_fsync_range+0x106/0x260 fs/sync.c:196 generic_write_sync include/linux/fs.h:2699 [inline] ext4_file_write_iter+0x883/0xdb0 fs/ext4/file.c:279 call_write_iter include/linux/fs.h:1788 [inline] new_sync_write fs/read_write.c:471 [inline] __vfs_write+0x401/0x5a0 fs/read_write.c:484 vfs_write+0x17f/0x4d0 fs/read_write.c:546 SYSC_write fs/read_write.c:594 [inline] SyS_write+0x102/0x250 fs/read_write.c:586 do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x7fcc3da4b19d RSP: 002b:00007fcc3bfebf90 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000400 RCX: 00007fcc3da4b19d RDX: 0000000000000400 RSI: 0000000000aafa90 RDI: 0000000000000001 RBP: 0000000000aafa90 R08: 3120333220706553 R09: 2036323a39353a30 R10: 656c6c616b7a7973 R11: 0000000000000293 R12: 0000000000000000 R13: 00007fcc3bfec410 R14: 0000000000ada710 R15: 0000000000aaf890 Code: ff ff 90 65 48 8b 04 25 c0 de 01 00 48 85 c0 74 1a 65 8b 15 7b c7 70 5c 81 e2 00 01 1f 00 75 0b 8b 90 a8 11 00 00 83 fa 01 74 01 48 c7 c2 00 00 00 81 48 81 ea 00 00 60 a3 48 03 14 24 48 8b