INFO: task syz-executor.0:14597 blocked for more than 140 seconds. Not tainted 4.14.224-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D29408 14597 13249 0x00000004 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3384 schedule+0x8d/0x1b0 kernel/sched/core.c:3428 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: 0033:0x465f69 RSP: 002b:00007fd60bdaa188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000465f69 RDX: 0000000000000004 RSI: 000000000000ab00 RDI: 0000000000000003 RBP: 00000000004bfa67 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60 R13: 00007ffd50b9322f R14: 00007fd60bdaa300 R15: 0000000000022000 INFO: task syz-executor.0:14610 blocked for more than 140 seconds. Not tainted 4.14.224-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D30168 14610 13249 0x00000004 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3384 schedule+0x8d/0x1b0 kernel/sched/core.c:3428 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3486 __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: 0033:0x465f69 RSP: 002b:00007fd60bd89188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000000000056c008 RCX: 0000000000465f69 RDX: 0000000000000004 RSI: 000000000000ab00 RDI: 0000000000000003 RBP: 00000000004bfa67 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c008 R13: 00007ffd50b9322f R14: 00007fd60bd89300 R15: 0000000000022000 INFO: task syz-executor.0:14616 blocked for more than 140 seconds. Not tainted 4.14.224-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D29824 14616 13249 0x00000004 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3384 schedule+0x8d/0x1b0 kernel/sched/core.c:3428 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3486 __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: 0033:0x465f69 RSP: 002b:00007fd60bd68188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000000000056c0b0 RCX: 0000000000465f69 RDX: 0000000000000006 RSI: 000000000000ab00 RDI: 0000000000000005 RBP: 00000000004bfa67 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c0b0 R13: 00007ffd50b9322f R14: 00007fd60bd68300 R15: 0000000000022000 INFO: task syz-executor.0:14622 blocked for more than 140 seconds. Not tainted 4.14.224-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D30168 14622 13249 0x00000004 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3384 schedule+0x8d/0x1b0 kernel/sched/core.c:3428 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3486 __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: 0033:0x465f69 RSP: 002b:00007fd60bd47188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000000000056c158 RCX: 0000000000465f69 RDX: 0000000000000006 RSI: 000000000000ab00 RDI: 0000000000000005 RBP: 00000000004bfa67 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c158 R13: 00007ffd50b9322f R14: 00007fd60bd47300 R15: 0000000000022000 INFO: task syz-executor.0:14630 blocked for more than 140 seconds. Not tainted 4.14.224-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D30168 14630 13249 0x00000004 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3384 schedule+0x8d/0x1b0 kernel/sched/core.c:3428 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3486 __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: 0033:0x465f69 RSP: 002b:00007fd60bd26188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000000000056c200 RCX: 0000000000465f69 RDX: 0000000000000006 RSI: 000000000000ab00 RDI: 0000000000000003 RBP: 00000000004bfa67 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c200 R13: 00007ffd50b9322f R14: 00007fd60bd26300 R15: 0000000000022000 INFO: task syz-executor.0:14635 blocked for more than 140 seconds. Not tainted 4.14.224-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D27896 14635 13249 0x00000004 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3384 schedule+0x8d/0x1b0 kernel/sched/core.c:3428 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3486 __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: 0033:0x465f69 RSP: 002b:00007fd60bd05188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000000000056c2a8 RCX: 0000000000465f69 RDX: 0000000000000004 RSI: 000000000000ab00 RDI: 0000000000000003 RBP: 00000000004bfa67 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c2a8 R13: 00007ffd50b9322f R14: 00007fd60bd05300 R15: 0000000000022000 Showing all locks held in the system: 1 lock held by khungtaskd/1531: #0: (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4548 2 locks held by agetty/7915: #0: (&tty->ldisc_sem){++++}, at: [] tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:284 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e3/0x1680 drivers/tty/n_tty.c:2156 1 lock held by syz-executor.0/14597: #0: (&nbd->config_lock){+.+.}, at: [] nbd_ioctl+0x11f/0xa80 drivers/block/nbd.c:1367 1 lock held by syz-executor.0/14610: #0: (&nbd->config_lock){+.+.}, at: [] nbd_ioctl+0x11f/0xa80 drivers/block/nbd.c:1367 1 lock held by syz-executor.0/14616: #0: (&nbd->config_lock){+.+.}, at: [] nbd_ioctl+0x11f/0xa80 drivers/block/nbd.c:1367 1 lock held by syz-executor.0/14622: #0: (&nbd->config_lock){+.+.}, at: [] nbd_ioctl+0x11f/0xa80 drivers/block/nbd.c:1367 1 lock held by syz-executor.0/14630: #0: (&nbd->config_lock){+.+.}, at: [] nbd_ioctl+0x11f/0xa80 drivers/block/nbd.c:1367 1 lock held by syz-executor.0/14635: #0: (&nbd->config_lock){+.+.}, at: [] nbd_ioctl+0x11f/0xa80 drivers/block/nbd.c:1367 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1531 Comm: khungtaskd Not tainted 4.14.224-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 CPU: 1 PID: 14519 Comm: syz-executor.1 Not tainted 4.14.224-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff8880968e6640 task.stack: ffff88808eb00000 RIP: 0010:__lock_acquire+0x4b1/0x3f20 kernel/locking/lockdep.c:3446 RSP: 0000:ffff88808eb07a10 EFLAGS: 00000006 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 1ffff11012d1cddd RSI: 0000000000000000 RDI: ffff8880968e6eec RBP: 0000000000000000 R08: 0000000000000001 R09: 00000000000c008d R10: ffff8880968e6ec8 R11: ffff8880968e6640 R12: ffff8880968e6ee0 R13: 000000000000008d R14: 000000000000008d R15: ffffffff8beb5d40 FS: 00007f1e54bb1700(0000) GS:ffff8880ba500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffc12ad50ff CR3: 00000000a5754000 CR4: 00000000001426e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x8c/0xc0 kernel/locking/spinlock.c:160 force_sig_info+0x51/0x410 kernel/signal.c:1243 force_sig_info_fault.constprop.0+0x185/0x260 arch/x86/mm/fault.c:225 __bad_area_nosemaphore+0x1d6/0x2c0 arch/x86/mm/fault.c:940 __bad_area arch/x86/mm/fault.c:974 [inline] bad_area_access_error+0x219/0x3e0 arch/x86/mm/fault.c:1013 __do_page_fault+0x4da/0xad0 arch/x86/mm/fault.c:1422 page_fault+0x45/0x50 arch/x86/entry/entry_64.S:1123 RIP: 12ad50ff:0x7f1e54bb1300 RSP: 56bf68:000000000056bf60 EFLAGS: 0056bf6c Code: c5 41 8b 42 20 41 09 e9 8b ac 24 c8 01 00 00 25 ff 1f 00 00 c1 e5 14 41 09 e9 41 09 c1 48 b8 00 00 00 00 00 fc ff df 45 89 4a 20 <0f> b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85