INFO: task syz-executor.0:1845 blocked for more than 140 seconds. Not tainted 4.14.131+ #13 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D24576 1845 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 blkdev_reread_part+0x1b/0x40 block/ioctl.c:192 loop_reread_partitions+0x72/0x80 drivers/block/loop.c:614 loop_clr_fd+0x828/0xac0 drivers/block/loop.c:1068 lo_ioctl+0x460/0x1a30 drivers/block/loop.c:1414 INFO: task syz-executor.3:1858 blocked for more than 140 seconds. Not tainted 4.14.131+ #13 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.3 D25592 1858 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: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/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/0x510 arch/x86/entry/common.c:292 INFO: task syz-executor.2:3072 blocked for more than 140 seconds. Not tainted 4.14.131+ #13 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D25160 3072 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: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/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/0x510 arch/x86/entry/common.c:292 INFO: task syz-executor.4:8483 blocked for more than 140 seconds. Not tainted 4.14.131+ #13 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D29152 8483 1860 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 loop_control_ioctl+0x71/0x300 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/0x510 arch/x86/entry/common.c:292 INFO: task syz-executor.4:8491 blocked for more than 140 seconds. Not tainted 4.14.131+ #13 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D29216 8491 1860 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 loop_control_ioctl+0x71/0x300 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/0x510 arch/x86/entry/common.c:292 INFO: task blkid:8484 blocked for more than 140 seconds. Not tainted 4.14.131+ #13 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. blkid D29136 8484 2814 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: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/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/0x510 arch/x86/entry/common.c:292 INFO: task syz-executor.1:8486 blocked for more than 140 seconds. Not tainted 4.14.131+ #13 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D26864 8486 1849 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 loop_control_ioctl+0x183/0x300 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/0x510 arch/x86/entry/common.c:292 INFO: task syz-executor.1:8495 blocked for more than 140 seconds. Not tainted 4.14.131+ #13 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D28960 8495 1849 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 loop_control_ioctl+0x71/0x300 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/0x510 arch/x86/entry/common.c:292 INFO: task blkid:8487 blocked for more than 140 seconds. Not tainted 4.14.131+ #13 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. blkid D27800 8487 2820 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: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/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/0x510 arch/x86/entry/common.c:292 INFO: task syz-executor.5:8490 blocked for more than 140 seconds. Not tainted 4.14.131+ #13 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D26864 8490 1844 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 loop_control_ioctl+0x71/0x300 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/0x510 arch/x86/entry/common.c:292 Showing all locks held in the system: 1 lock held by khungtaskd/23: #0: (tasklist_lock){.+.+}, at: [<000000002e55ff8b>] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4541 1 lock held by rsyslogd/1634: #0: (&f->f_pos_lock){+.+.}, at: [<0000000033dc0a5c>] __fdget_pos+0xa6/0xc0 fs/file.c:769 2 locks held by getty/1762: #0: (&tty->ldisc_sem){++++}, at: [<00000000fbf75b36>] tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:284 #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000c6cc2b13>] n_tty_read+0x1f7/0x1700 drivers/tty/n_tty.c:2156 2 locks held by syz-executor.0/1845: #0: (&lo->lo_ctl_mutex/1){+.+.}, at: [<00000000e7eafceb>] lo_ioctl+0x86/0x1a30 drivers/block/loop.c:1404 #1: (&bdev->bd_mutex){+.+.}, at: [<00000000dc6ccc08>] blkdev_reread_part+0x1b/0x40 block/ioctl.c:192 2 locks held by syz-executor.3/1858: #0: (&bdev->bd_mutex){+.+.}, at: [<000000002ae82757>] __blkdev_get+0xf3/0xf90 fs/block_dev.c:1457 #1: (loop_index_mutex){+.+.}, at: [<000000005e6785fa>] lo_open+0x19/0xb0 drivers/block/loop.c:1623 2 locks held by syz-executor.2/3072: #0: (&bdev->bd_mutex){+.+.}, at: [<000000002ae82757>] __blkdev_get+0xf3/0xf90 fs/block_dev.c:1457 #1: (loop_index_mutex){+.+.}, at: [<000000005e6785fa>] lo_open+0x19/0xb0 drivers/block/loop.c:1623 1 lock held by syz-executor.4/8483: #0: (loop_index_mutex){+.+.}, at: [<000000006005825c>] loop_control_ioctl+0x71/0x300 drivers/block/loop.c:1982 1 lock held by syz-executor.4/8491: #0: (loop_index_mutex){+.+.}, at: [<000000006005825c>] loop_control_ioctl+0x71/0x300 drivers/block/loop.c:1982 2 locks held by blkid/8484: #0: (&bdev->bd_mutex){+.+.}, at: [<000000002ae82757>] __blkdev_get+0xf3/0xf90 fs/block_dev.c:1457 #1: (loop_index_mutex){+.+.}, at: [<000000005e6785fa>] lo_open+0x19/0xb0 drivers/block/loop.c:1623 2 locks held by syz-executor.1/8486: #0: (loop_index_mutex){+.+.}, at: [<000000006005825c>] loop_control_ioctl+0x71/0x300 drivers/block/loop.c:1982 #1: (&lo->lo_ctl_mutex#2){+.+.}, at: [<00000000957e7ebb>] loop_control_ioctl+0x183/0x300 drivers/block/loop.c:1996 1 lock held by syz-executor.1/8495: #0: (loop_index_mutex){+.+.}, at: [<000000006005825c>] loop_control_ioctl+0x71/0x300 drivers/block/loop.c:1982 2 locks held by blkid/8487: #0: (&bdev->bd_mutex){+.+.}, at: [<000000002ae82757>] __blkdev_get+0xf3/0xf90 fs/block_dev.c:1457 #1: (loop_index_mutex){+.+.}, at: [<000000005e6785fa>] lo_open+0x19/0xb0 drivers/block/loop.c:1623 1 lock held by syz-executor.5/8490: #0: (loop_index_mutex){+.+.}, at: [<000000006005825c>] loop_control_ioctl+0x71/0x300 drivers/block/loop.c:1982 2 locks held by blkid/8489: #0: (&bdev->bd_mutex){+.+.}, at: [<000000002ae82757>] __blkdev_get+0xf3/0xf90 fs/block_dev.c:1457 #1: (loop_index_mutex){+.+.}, at: [<000000005e6785fa>] lo_open+0x19/0xb0 drivers/block/loop.c:1623 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 23 Comm: khungtaskd Not tainted 4.14.131+ #13 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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.14.131+ #13 task: 00000000335e564f task.stack: 00000000ba8eb205 RIP: 0010:native_apic_mem_write+0x8/0x10 arch/x86/include/asm/apic.h:100 RSP: 0018:ffffffffa6607bc8 EFLAGS: 00000046 RAX: ffffffffa429c1e0 RBX: ffffffffa64a7880 RCX: 0000000000000020 RDX: 1ffffffff4c94f2d RSI: 000000000006211a RDI: 0000000000000380 RBP: ffff8881dba1df40 R08: ffff88821fffd01c R09: ffff88821fffd008 R10: ffff88821fffd010 R11: 00000065306727f0 R12: 000000000006211a R13: 0000000000000003 R14: 0000000000000000 R15: ffff8881dba249c0 FS: 0000000000000000(0000) GS:ffff8881dba00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000001c4e000 CR3: 000000001ea26006 CR4: 00000000001606b0 Call Trace: apic_write arch/x86/include/asm/apic.h:395 [inline] lapic_next_event+0x59/0x90 arch/x86/kernel/apic/apic.c:469 clockevents_program_event+0x1fd/0x2e0 kernel/time/clockevents.c:339 tick_program_event+0x78/0xd0 kernel/time/tick-oneshot.c:47 hrtimer_reprogram kernel/time/hrtimer.c:665 [inline] hrtimer_start_range_ns+0xd2a/0x1080 kernel/time/hrtimer.c:995 hrtimer_start_expires include/linux/hrtimer.h:391 [inline] tick_nohz_restart kernel/time/tick-sched.c:663 [inline] tick_nohz_restart_sched_tick kernel/time/tick-sched.c:877 [inline] __tick_nohz_idle_restart_tick+0x2bc/0x390 kernel/time/tick-sched.c:1159 tick_nohz_idle_exit+0x202/0x320 kernel/time/tick-sched.c:1197 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: 83 3d fc e3 db 02 01 77 02 5d c3 89 ef 5d e9 7a e7 fe ff 48 c7 c7 c0 a5 05 a7 e8 c4 6c 49 00 eb df 66 90 89 ff 89 b7 00 d0 5f ff 0f 1f 80 00 00 00 00 48 b8 00 00 00 00 00 fc ff df 53 89 fb