INFO: task kworker/1:0:18 blocked for more than 140 seconds. Not tainted 4.14.198-syzkaller #0 Bluetooth: hci5 command 0x0409 tx timeout FAT-fs (loop4): Unrecognized mount option "mask=^MAY_APPEND" or missing value "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. audit: type=1800 audit(1601713114.010:38): pid=30788 uid=0 auid=0 ses=4 subj=system_u:system_r:kernel_t:s0 op="collect_data" cause="failed" comm="syz-executor.3" name="file0" dev="sda1" ino=16249 res=0 kworker/1:0 D25696 18 2 0x80000000 Workqueue: usb_hub_wq hub_event 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 usb_kill_urb.part.0+0x125/0x190 drivers/usb/core/urb.c:691 usb_kill_urb+0x7c/0x90 drivers/usb/core/urb.c:686 usb_start_wait_urb+0x206/0x260 drivers/usb/core/message.c:62 usb_internal_control_msg drivers/usb/core/message.c:100 [inline] usb_control_msg+0x302/0x450 drivers/usb/core/message.c:151 hub_port_init+0xfb1/0x28b0 drivers/usb/core/hub.c:4555 hub_port_connect drivers/usb/core/hub.c:4905 [inline] hub_port_connect_change drivers/usb/core/hub.c:5088 [inline] port_event drivers/usb/core/hub.c:5194 [inline] hub_event+0x1bc5/0x39a0 drivers/usb/core/hub.c:5274 process_one_work+0x793/0x14a0 kernel/workqueue.c:2116 worker_thread+0x5cc/0xff0 kernel/workqueue.c:2250 kthread+0x30d/0x420 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 Showing all locks held in the system: 5 locks held by kworker/1:0/18: #0: ("usb_hub_wq"){+.+.}, at: [] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087 #1: ((&hub->events)){+.+.}, at: [] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091 #2: (&dev->mutex){....}, at: [] device_lock include/linux/device.h:1081 [inline] #2: (&dev->mutex){....}, at: [] hub_event+0xfc/0x39a0 drivers/usb/core/hub.c:5220 #3: (&port_dev->status_lock){+.+.}, at: [] usb_lock_port drivers/usb/core/hub.c:2934 [inline] #3: (&port_dev->status_lock){+.+.}, at: [] hub_port_connect drivers/usb/core/hub.c:4904 [inline] #3: (&port_dev->status_lock){+.+.}, at: [] hub_port_connect_change drivers/usb/core/hub.c:5088 [inline] #3: (&port_dev->status_lock){+.+.}, at: [] port_event drivers/usb/core/hub.c:5194 [inline] #3: (&port_dev->status_lock){+.+.}, at: [] hub_event+0x1bb0/0x39a0 drivers/usb/core/hub.c:5274 #4: (hcd->address0_mutex){+.+.}, at: [] hub_port_init+0x15b/0x28b0 drivers/usb/core/hub.c:4429 1 lock held by khungtaskd/1067: #0: (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4548 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1067 Comm: khungtaskd Not tainted 4.14.198-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+0x1b2/0x283 lib/dump_stack.c:58 nmi_cpu_backtrace.cold+0x57/0x93 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x13a/0x17f 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: 3654 Comm: systemd-udevd Not tainted 4.14.198-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff88808eb803c0 task.stack: ffff88808eb88000 RIP: 0010:lock_is_held_type+0x30/0x210 kernel/locking/lockdep.c:4029 RSP: 0018:ffff88808eb8f740 EFLAGS: 00000a07 RAX: dffffc0000000000 RBX: ffff88808eb803c0 RCX: 0000000000000001 RDX: 0000000000000000 RSI: 00000000ffffffff RDI: ffff88808eb80c44 RBP: ffffffff87d84de0 R08: ffffffff8a0ace40 R09: 0000000000000001 R10: 0000000000000000 R11: ffff88808eb803c0 R12: 0000000000000bf9 R13: 00000000014000c0 R14: ffff88821f8b9680 R15: ffff88808eb8fd18 FS: 00007f329ca7f8c0(0000) GS:ffff8880aeb00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000016a9e60 CR3: 000000008e52e000 CR4: 00000000001426e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_is_held include/linux/lockdep.h:437 [inline] ___might_sleep+0x227/0x2b0 kernel/sched/core.c:6007 cache_alloc_debugcheck_before mm/slab.c:3065 [inline] slab_alloc mm/slab.c:3380 [inline] kmem_cache_alloc+0x2be/0x3c0 mm/slab.c:3550 __d_alloc+0x2a/0xa20 fs/dcache.c:1623 d_alloc+0x46/0x240 fs/dcache.c:1710 d_alloc_parallel+0xd6/0x16b0 fs/dcache.c:2492 lookup_slow+0x175/0x400 fs/namei.c:1679 walk_component+0x6a1/0xbc0 fs/namei.c:1825 lookup_last fs/namei.c:2293 [inline] path_lookupat+0x1bb/0x780 fs/namei.c:2343 filename_lookup+0x18a/0x510 fs/namei.c:2377 user_path_at include/linux/namei.h:57 [inline] SYSC_faccessat fs/open.c:403 [inline] SyS_faccessat+0x21b/0x680 fs/open.c:353 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7f329b8f29c7 RSP: 002b:00007ffff721b478 EFLAGS: 00000246 ORIG_RAX: 0000000000000015 RAX: ffffffffffffffda RBX: 0000561995089980 RCX: 00007f329b8f29c7 RDX: 00746e657665752f RSI: 0000000000000000 RDI: 00007ffff721b480 RBP: 00007ffff721b4f0 R08: 000000000000c480 R09: 0000000000001010 R10: 0000000000000020 R11: 0000000000000246 R12: 0000561994b73856 R13: 0000561995080c40 R14: 00007ffff721b480 R15: 0000561995090bf0 Code: 00 00 fc ff df 41 54 55 48 89 fd 53 65 48 8b 1c 25 40 ee 01 00 48 8d bb 84 08 00 00 48 83 ec 08 48 89 fa 48 c1 ea 03 0f b6 14 02 <48> 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 5e 01 00 00