[info] Using makefile-style concurrent boot in runlevel 2. [ 15.462424][ C1] random: crng init done [....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.0.132' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 29.882881][ T12] usb 1-1: new high-speed USB device number 2 using dummy_hcd [ 30.242925][ T12] usb 1-1: config 0 has an invalid interface number: 135 but max is 0 [ 30.251807][ T12] usb 1-1: config 0 has no interface number 0 [ 30.258131][ T12] usb 1-1: config 0 interface 135 altsetting 0 has an invalid endpoint with address 0x0, skipping [ 30.268835][ T12] usb 1-1: config 0 interface 135 altsetting 0 endpoint 0x81 has an invalid bInterval 169, changing to 11 [ 30.280297][ T12] usb 1-1: config 0 interface 135 altsetting 0 endpoint 0x81 has invalid maxpacket 1646, setting to 1024 [ 30.302870][ T12] usb 1-1: config 0 interface 135 altsetting 0 has 2 endpoint descriptors, different from the interface descriptor's value: 1 [ 30.316037][ T12] usb 1-1: New USB device found, idVendor=07c0, idProduct=1501, bcdDevice=65.14 [ 30.325226][ T12] usb 1-1: New USB device strings: Mfr=0, Product=0, SerialNumber=0 [ 30.335066][ T12] usb 1-1: config 0 descriptor?? [ 30.378015][ T12] iowarrior 1-1:0.135: IOWarrior product=0x1501, serial= interface=135 now attached to iowarrior0 [ 30.574642][ T12] usb 1-1: USB disconnect, device number 2 [ 30.593894][ T12] [ 30.596279][ T12] ====================================================== [ 30.603317][ T12] WARNING: possible circular locking dependency detected [ 30.610361][ T12] 5.3.0-rc2+ #25 Not tainted [ 30.614969][ T12] ------------------------------------------------------ [ 30.621997][ T12] kworker/0:1/12 is trying to acquire lock: [ 30.627898][ T12] 0000000041073ed4 (minor_rwsem){++++}, at: usb_deregister_dev+0x61/0x270 [ 30.636489][ T12] [ 30.636489][ T12] but task is already holding lock: [ 30.643871][ T12] 000000003de63af8 (iowarrior_open_disc_lock){+.+.}, at: iowarrior_disconnect+0x45/0x2c0 [ 30.653680][ T12] [ 30.653680][ T12] which lock already depends on the new lock. [ 30.653680][ T12] [ 30.664246][ T12] [ 30.664246][ T12] the existing dependency chain (in reverse order) is: [ 30.673417][ T12] [ 30.673417][ T12] -> #2 (iowarrior_open_disc_lock){+.+.}: [ 30.681310][ T12] __mutex_lock+0x158/0x1360 [ 30.686415][ T12] iowarrior_open+0x8a/0x2a0 [ 30.691522][ T12] usb_open+0x1df/0x270 [ 30.696515][ T12] chrdev_open+0x219/0x5c0 [ 30.701446][ T12] do_dentry_open+0x494/0x1120 [ 30.706718][ T12] path_openat+0x1430/0x3f50 [ 30.711919][ T12] do_filp_open+0x1a1/0x280 [ 30.716940][ T12] do_sys_open+0x3c0/0x580 [ 30.721864][ T12] do_syscall_64+0xb7/0x580 [ 30.726892][ T12] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 30.733283][ T12] [ 30.733283][ T12] -> #1 (iowarrior_mutex){+.+.}: [ 30.740386][ T12] __mutex_lock+0x158/0x1360 [ 30.745487][ T12] iowarrior_open+0x23/0x2a0 [ 30.750598][ T12] usb_open+0x1df/0x270 [ 30.755293][ T12] chrdev_open+0x219/0x5c0 [ 30.760228][ T12] do_dentry_open+0x494/0x1120 [ 30.765517][ T12] path_openat+0x1430/0x3f50 [ 30.770624][ T12] do_filp_open+0x1a1/0x280 [ 30.775672][ T12] do_sys_open+0x3c0/0x580 [ 30.780608][ T12] do_syscall_64+0xb7/0x580 [ 30.785628][ T12] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 30.792021][ T12] [ 30.792021][ T12] -> #0 (minor_rwsem){++++}: [ 30.798865][ T12] __lock_acquire+0x1f7c/0x3b50 [ 30.804226][ T12] lock_acquire+0x127/0x320 [ 30.809327][ T12] down_write+0x92/0x150 [ 30.814076][ T12] usb_deregister_dev+0x61/0x270 [ 30.820954][ T12] iowarrior_disconnect+0xa8/0x2c0 [ 30.826573][ T12] usb_unbind_interface+0x1bd/0x8a0 [ 30.832284][ T12] device_release_driver_internal+0x404/0x4c0 [ 30.838864][ T12] bus_remove_device+0x2dc/0x4a0 [ 30.844311][ T12] device_del+0x420/0xb10 [ 30.849166][ T12] usb_disable_device+0x211/0x690 [ 30.854725][ T12] usb_disconnect+0x284/0x8d0 [ 30.860096][ T12] hub_event+0x1454/0x3640 [ 30.865145][ T12] process_one_work+0x92b/0x1530 [ 30.870597][ T12] worker_thread+0x96/0xe20 [ 30.875639][ T12] kthread+0x318/0x420 [ 30.880220][ T12] ret_from_fork+0x24/0x30 [ 30.885160][ T12] [ 30.885160][ T12] other info that might help us debug this: [ 30.885160][ T12] [ 30.895463][ T12] Chain exists of: [ 30.895463][ T12] minor_rwsem --> iowarrior_mutex --> iowarrior_open_disc_lock [ 30.895463][ T12] [ 30.909169][ T12] Possible unsafe locking scenario: [ 30.909169][ T12] [ 30.916658][ T12] CPU0 CPU1 [ 30.922037][ T12] ---- ---- [ 30.927389][ T12] lock(iowarrior_open_disc_lock); [ 30.932584][ T12] lock(iowarrior_mutex); [ 30.939526][ T12] lock(iowarrior_open_disc_lock); [ 30.947223][ T12] lock(minor_rwsem); [ 30.951273][ T12] [ 30.951273][ T12] *** DEADLOCK *** [ 30.951273][ T12] [ 30.959425][ T12] 6 locks held by kworker/0:1/12: [ 30.964430][ T12] #0: 00000000199c7bd5 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x827/0x1530 [ 30.974601][ T12] #1: 000000006e079ed1 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x85b/0x1530 [ 30.985300][ T12] #2: 000000002179688b (&dev->mutex){....}, at: hub_event+0x17c/0x3640 [ 30.993814][ T12] #3: 000000009ab53871 (&dev->mutex){....}, at: usb_disconnect+0x91/0x8d0 [ 31.002934][ T12] #4: 000000006ef0693e (&dev->mutex){....}, at: device_release_driver_internal+0x23/0x4c0 [ 31.012915][ T12] #5: 000000003de63af8 (iowarrior_open_disc_lock){+.+.}, at: iowarrior_disconnect+0x45/0x2c0 [ 31.023144][ T12] [ 31.023144][ T12] stack backtrace: [ 31.029041][ T12] CPU: 0 PID: 12 Comm: kworker/0:1 Not tainted 5.3.0-rc2+ #25 [ 31.036488][ T12] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 31.046567][ T12] Workqueue: usb_hub_wq hub_event [ 31.051683][ T12] Call Trace: [ 31.054966][ T12] dump_stack+0xca/0x13e [ 31.059200][ T12] check_noncircular+0x345/0x3e0 [ 31.064125][ T12] ? print_circular_bug+0x1b0/0x1b0 [ 31.069310][ T12] ? __lock_acquire+0x2605/0x3b50 [ 31.074335][ T12] ? graph_lock+0x80/0x180 [ 31.078748][ T12] ? hlock_class+0x120/0x120 [ 31.083326][ T12] ? mark_lock+0xbc/0x1130 [ 31.087754][ T12] ? find_first_zero_bit+0x94/0xb0 [ 31.092905][ T12] __lock_acquire+0x1f7c/0x3b50 [ 31.098029][ T12] ? mark_held_locks+0xe0/0xe0 [ 31.102810][ T12] ? __mutex_lock+0x430/0x1360 [ 31.107598][ T12] ? usb_kill_urb+0x198/0x2c0 [ 31.112274][ T12] lock_acquire+0x127/0x320 [ 31.116772][ T12] ? usb_deregister_dev+0x61/0x270 [ 31.121875][ T12] down_write+0x92/0x150 [ 31.126142][ T12] ? usb_deregister_dev+0x61/0x270 [ 31.131264][ T12] ? __down_timeout+0x2d0/0x2d0 [ 31.136143][ T12] usb_deregister_dev+0x61/0x270 [ 31.141080][ T12] iowarrior_disconnect+0xa8/0x2c0 [ 31.146217][ T12] usb_unbind_interface+0x1bd/0x8a0 [ 31.151409][ T12] ? usb_autoresume_device+0x60/0x60 [ 31.156775][ T12] device_release_driver_internal+0x404/0x4c0 [ 31.163011][ T12] bus_remove_device+0x2dc/0x4a0 [ 31.167963][ T12] device_del+0x420/0xb10 [ 31.172283][ T12] ? __device_links_no_driver+0x240/0x240 [ 31.177988][ T12] ? usb_remove_ep_devs+0x3e/0x80 [ 31.183001][ T12] ? remove_intf_ep_devs+0x13f/0x1d0 [ 31.188276][ T12] usb_disable_device+0x211/0x690 [ 31.193295][ T12] usb_disconnect+0x284/0x8d0 [ 31.197962][ T12] hub_event+0x1454/0x3640 [ 31.202370][ T12] ? find_held_lock+0x2d/0x110 [ 31.207126][ T12] ? mark_held_locks+0xe0/0xe0 [ 31.211881][ T12] ? hub_port_debounce+0x260/0x260 [ 31.216988][ T12] process_one_work+0x92b/0x1530 [ 31.221918][ T12] ? pwq_dec_nr_in_flight+0x310/0x310 [ 31