INFO: task syz-executor.5:1824 blocked for more than 140 seconds. Not tainted 4.14.136+ #28 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D24984 1824 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:3455 [inline] path_openat+0xb6c/0x2be0 fs/namei.c:3597 do_filp_open+0x1a1/0x280 fs/namei.c:3631 do_sys_open+0x2ca/0x590 fs/open.c:1096 do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292 INFO: task syz-executor.4:1839 blocked for more than 140 seconds. Not tainted 4.14.136+ #28 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D25328 1839 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:3455 [inline] path_openat+0xb6c/0x2be0 fs/namei.c:3597 do_filp_open+0x1a1/0x280 fs/namei.c:3631 do_sys_open+0x2ca/0x590 fs/open.c:1096 do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292 INFO: task syz-executor.1:3806 blocked for more than 140 seconds. Not tainted 4.14.136+ #28 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D25008 3806 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:3455 [inline] path_openat+0xb6c/0x2be0 fs/namei.c:3597 do_filp_open+0x1a1/0x280 fs/namei.c:3631 do_sys_open+0x2ca/0x590 fs/open.c:1096 do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292 INFO: task syz-executor.3:5840 blocked for more than 140 seconds. Not tainted 4.14.136+ #28 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.3 D25512 5840 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:3455 [inline] path_openat+0xb6c/0x2be0 fs/namei.c:3597 do_filp_open+0x1a1/0x280 fs/namei.c:3631 do_sys_open+0x2ca/0x590 fs/open.c:1096 do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292 INFO: task syz-executor.0:6384 blocked for more than 140 seconds. Not tainted 4.14.136+ #28 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D26960 6384 1832 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_reread_part+0x1b/0x40 block/ioctl.c:192 loop_reread_partitions+0x7f/0x90 drivers/block/loop.c:614 loop_clr_fd+0x835/0xad0 drivers/block/loop.c:1068 lo_ioctl+0x460/0x1a30 drivers/block/loop.c:1414 INFO: task blkid:6386 blocked for more than 140 seconds. Not tainted 4.14.136+ #28 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. blkid D28928 6386 299 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:3455 [inline] path_openat+0xb6c/0x2be0 fs/namei.c:3597 do_filp_open+0x1a1/0x280 fs/namei.c:3631 do_sys_open+0x2ca/0x590 fs/open.c:1096 do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292 INFO: task syz-executor.2:6390 blocked for more than 140 seconds. Not tainted 4.14.136+ #28 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D29224 6390 5391 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 INFO: task syz-executor.2:6397 blocked for more than 140 seconds. Not tainted 4.14.136+ #28 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D29952 6397 5391 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 INFO: task syz-executor.2:6403 blocked for more than 140 seconds. Not tainted 4.14.136+ #28 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D28928 6403 5391 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 INFO: task syz-executor.2:6404 blocked for more than 140 seconds. Not tainted 4.14.136+ #28 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D28928 6404 5391 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 Showing all locks held in the system: 1 lock held by khungtaskd/23: #0: (tasklist_lock){.+.+}, at: [<00000000cf8274a2>] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4541 1 lock held by rsyslogd/1623: #0: (&f->f_pos_lock){+.+.}, at: [<000000007473c70d>] __fdget_pos+0xb5/0xd0 fs/file.c:769 2 locks held by getty/1751: #0: (&tty->ldisc_sem){++++}, at: [<00000000392bd107>] tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:284 #1: (&ldata->atomic_read_lock){+.+.}, at: [<000000006dd80724>] n_tty_read+0x1f7/0x1700 drivers/tty/n_tty.c:2156 1 lock held by syz-executor.5/1824: #0: (&bdev->bd_mutex){+.+.}, at: [<00000000a535fdeb>] __blkdev_get+0xf3/0xf90 fs/block_dev.c:1457 2 locks held by syz-executor.4/1839: #0: (&bdev->bd_mutex){+.+.}, at: [<00000000a535fdeb>] __blkdev_get+0xf3/0xf90 fs/block_dev.c:1457 #1: (loop_index_mutex){+.+.}, at: [<0000000064e94245>] lo_open+0x19/0xb0 drivers/block/loop.c:1623 2 locks held by syz-executor.1/3806: #0: (&bdev->bd_mutex){+.+.}, at: [<00000000a535fdeb>] __blkdev_get+0xf3/0xf90 fs/block_dev.c:1457 #1: (loop_index_mutex){+.+.}, at: [<0000000064e94245>] lo_open+0x19/0xb0 drivers/block/loop.c:1623 1 lock held by syz-executor.3/5840: #0: (&bdev->bd_mutex){+.+.}, at: [<00000000a535fdeb>] __blkdev_get+0xf3/0xf90 fs/block_dev.c:1457 2 locks held by syz-executor.0/6384: #0: (&lo->lo_ctl_mutex/1){+.+.}, at: [<000000004d611635>] lo_ioctl+0x86/0x1a30 drivers/block/loop.c:1404 #1: (&bdev->bd_mutex){+.+.}, at: [<000000006008eb6b>] blkdev_reread_part+0x1b/0x40 block/ioctl.c:192 2 locks held by blkid/6386: #0: (&bdev->bd_mutex){+.+.}, at: [<00000000a535fdeb>] __blkdev_get+0xf3/0xf90 fs/block_dev.c:1457 #1: (loop_index_mutex){+.+.}, at: [<0000000064e94245>] lo_open+0x19/0xb0 drivers/block/loop.c:1623 2 locks held by syz-executor.2/6390: #0: (loop_index_mutex){+.+.}, at: [<000000006cee9c72>] loop_control_ioctl+0x71/0x310 drivers/block/loop.c:1982 #1: (&lo->lo_ctl_mutex#2){+.+.}, at: [<00000000ba3597a8>] loop_control_ioctl+0x183/0x310 drivers/block/loop.c:1996 1 lock held by syz-executor.2/6397: #0: (loop_index_mutex){+.+.}, at: [<000000006cee9c72>] loop_control_ioctl+0x71/0x310 drivers/block/loop.c:1982 1 lock held by syz-executor.2/6403: #0: (loop_index_mutex){+.+.}, at: [<000000006cee9c72>] loop_control_ioctl+0x71/0x310 drivers/block/loop.c:1982 1 lock held by syz-executor.2/6404: #0: (loop_index_mutex){+.+.}, at: [<000000006cee9c72>] loop_control_ioctl+0x71/0x310 drivers/block/loop.c:1982 2 locks held by blkid/6394: #0: (&bdev->bd_mutex){+.+.}, at: [<00000000a535fdeb>] __blkdev_get+0xf3/0xf90 fs/block_dev.c:1457 #1: (loop_index_mutex){+.+.}, at: [<0000000064e94245>] lo_open+0x19/0xb0 drivers/block/loop.c:1623 2 locks held by blkid/6395: #0: (&bdev->bd_mutex){+.+.}, at: [<00000000a535fdeb>] __blkdev_get+0xf3/0xf90 fs/block_dev.c:1457 #1: (loop_index_mutex){+.+.}, at: [<0000000064e94245>] lo_open+0x19/0xb0 drivers/block/loop.c:1623 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 23 Comm: khungtaskd Not tainted 4.14.136+ #28 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 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.14.136+ #28 task: 000000008be721b4 task.stack: 00000000f0784d2a RIP: 0010:mark_lock+0xa6/0xfc0 kernel/locking/lockdep.c:3164 RSP: 0018:ffffffffa6a07a70 EFLAGS: 00000046 RAX: dffffc0000000000 RBX: ffffffffa7b64860 RCX: 1ffffffff4d46292 RDX: 1ffffffff4f6c912 RSI: ffffffffa6a31470 RDI: ffffffffa7b64890 RBP: ffffffffa6a31470 R08: 0000000000000001 R09: 0000000000000000 R10: ffffffffa6a31470 R11: 0000000000000031 R12: 0000000000000100 R13: ffffffffa6a31490 R14: ffffffffa6a30c40 R15: 0000000000000008 FS: 0000000000000000(0000) GS:ffff8881dba00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fcc8f606f80 CR3: 000000018c826006 CR4: 00000000001606b0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 Call Trace: __lock_acquire+0x5d7/0x4320 kernel/locking/lockdep.c:3448 lock_acquire+0x12b/0x360 kernel/locking/lockdep.c:3991 seqcount_lockdep_reader_access include/linux/seqlock.h:81 [inline] read_seqcount_begin include/linux/seqlock.h:164 [inline] ktime_get kernel/time/timekeeping.c:760 [inline] ktime_get+0x68/0x1b0 kernel/time/timekeeping.c:750 tick_nohz_idle_exit+0x183/0x320 kernel/time/tick-sched.c:1191 do_idle+0x212/0x390 kernel/sched/idle.c:281 cpu_startup_entry+0xc6/0xd0 kernel/sched/idle.c:374 start_kernel+0x712/0x74a init/main.c:709 secondary_startup_64+0xa5/0xb0 arch/x86/kernel/head_64.S:240 Code: 50 01 00 00 48 81 eb 50 01 00 00 48 81 c3 60 09 b6 a7 48 8d 7b 30 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 <0f> 85 bc 0b 00 00 4c 85 63 30 0f 84 a0 00 00 00 41 bc 01 00 00