block nbd0: shutting down sockets INFO: task syz-executor324:7989 blocked for more than 140 seconds. Not tainted 4.14.259-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor324 D29824 7989 7978 0x00000004 Call Trace: context_switch kernel/sched/core.c:2811 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3387 schedule+0x8d/0x1b0 kernel/sched/core.c:3431 blk_mq_freeze_queue_wait+0xf8/0x1f0 block/blk-mq.c:154 nbd_add_socket+0x158/0x7e0 drivers/block/nbd.c:959 __nbd_ioctl drivers/block/nbd.c:1307 [inline] nbd_ioctl+0x394/0xa80 drivers/block/nbd.c:1374 __blkdev_driver_ioctl block/ioctl.c:297 [inline] blkdev_ioctl+0x540/0x1830 block/ioctl.c:594 block_ioctl+0xd9/0x120 fs/block_dev.c:1893 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0x75a/0xff0 fs/ioctl.c:684 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7fc7a9784299 RSP: 002b:00007fc7a9731308 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fc7a98084e8 RCX: 00007fc7a9784299 RDX: 0000000000000004 RSI: 000000000000ab00 RDI: 0000000000000006 RBP: 00007fc7a98084e0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fc7a98084ec R13: 00007fc7a97d508c R14: 64626e2f7665642f R15: 0000000000022000 INFO: task syz-executor324:7990 blocked for more than 140 seconds. Not tainted 4.14.259-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor324 D30088 7990 7978 0x00000004 Call Trace: context_switch kernel/sched/core.c:2811 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3387 schedule+0x8d/0x1b0 kernel/sched/core.c:3431 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3489 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x669/0x1310 kernel/locking/mutex.c:893 nbd_ioctl+0x11f/0xa80 drivers/block/nbd.c:1367 __blkdev_driver_ioctl block/ioctl.c:297 [inline] blkdev_ioctl+0x540/0x1830 block/ioctl.c:594 block_ioctl+0xd9/0x120 fs/block_dev.c:1893 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0x75a/0xff0 fs/ioctl.c:684 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7fc7a9784299 RSP: 002b:00007fc7a9710308 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fc7a98084f8 RCX: 00007fc7a9784299 RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000006 RBP: 00007fc7a98084f0 R08: 00007fc7a9710700 R09: 0000000000000000 R10: 00007fc7a9710700 R11: 0000000000000246 R12: 00007fc7a98084fc R13: 00007fc7a97d508c R14: 64626e2f7665642f R15: 0000000000022000 INFO: task syz-executor324:7991 blocked for more than 140 seconds. Not tainted 4.14.259-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor324 D29824 7991 7978 0x00000004 Call Trace: context_switch kernel/sched/core.c:2811 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3387 schedule+0x8d/0x1b0 kernel/sched/core.c:3431 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3489 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x669/0x1310 kernel/locking/mutex.c:893 nbd_ioctl+0x11f/0xa80 drivers/block/nbd.c:1367 __blkdev_driver_ioctl block/ioctl.c:297 [inline] blkdev_ioctl+0x540/0x1830 block/ioctl.c:594 block_ioctl+0xd9/0x120 fs/block_dev.c:1893 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0x75a/0xff0 fs/ioctl.c:684 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7fc7a9784299 RSP: 002b:00007fc7a96ef308 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fc7a9808508 RCX: 00007fc7a9784299 RDX: 0000000000000005 RSI: 000000000000ab07 RDI: 0000000000000007 RBP: 00007fc7a9808500 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fc7a980850c R13: 00007fc7a97d508c R14: 64626e2f7665642f R15: 0000000000022000 Showing all locks held in the system: 1 lock held by khungtaskd/1494: #0: (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4548 1 lock held by syz-executor324/7989: #0: (&nbd->config_lock){+.+.}, at: [] nbd_ioctl+0x11f/0xa80 drivers/block/nbd.c:1367 1 lock held by syz-executor324/7990: #0: (&nbd->config_lock){+.+.}, at: [] nbd_ioctl+0x11f/0xa80 drivers/block/nbd.c:1367 1 lock held by syz-executor324/7991: #0: (&nbd->config_lock){+.+.}, at: [] nbd_ioctl+0x11f/0xa80 drivers/block/nbd.c:1367 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1494 Comm: khungtaskd Not tainted 4.14.259-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x1b2/0x281 lib/dump_stack.c:58 nmi_cpu_backtrace.cold+0x57/0x93 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x13a/0x180 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+0x5b9/0xb40 kernel/hung_task.c:274 kthread+0x30d/0x420 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 skipped: idling at pc 0xffffffff8723eb8e