Hello, syzbot found the following issue on: HEAD commit: d598c3c46ea6 Merge 5.16-rc4 into usb-next git tree: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing console output: https://syzkaller.appspot.com/x/log.txt?x=114b5f3db00000 kernel config: https://syzkaller.appspot.com/x/.config?x=c6df5f09a0b9c823 dashboard link: https://syzkaller.appspot.com/bug?extid=353b9bb3bcc881d85a46 compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2 Unfortunately, I don't have any reproducer for this issue yet. IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+353b9bb3bcc881d85a46@xxxxxxxxxxxxxxxxxxxxxxxxx dvb-usb: could not initialize remote control. dvb-usb: PCTV 2002e SE successfully initialized and connected. usb 2-1: USB disconnect, device number 3 ------------[ cut here ]------------ DEBUG_LOCKS_WARN_ON(lock->magic != lock) WARNING: CPU: 1 PID: 4005 at kernel/locking/mutex.c:586 __mutex_lock_common kernel/locking/mutex.c:586 [inline] WARNING: CPU: 1 PID: 4005 at kernel/locking/mutex.c:586 __mutex_lock+0x9ec/0x12f0 kernel/locking/mutex.c:740 Modules linked in: CPU: 1 PID: 4005 Comm: kworker/1:3 Not tainted 5.16.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: usb_hub_wq hub_event RIP: 0010:__mutex_lock_common kernel/locking/mutex.c:586 [inline] RIP: 0010:__mutex_lock+0x9ec/0x12f0 kernel/locking/mutex.c:740 Code: 08 84 d2 0f 85 19 08 00 00 8b 05 67 e0 e6 02 85 c0 0f 85 27 f7 ff ff 48 c7 c6 20 80 27 86 48 c7 c7 a0 7e 27 86 e8 8e 27 d2 ff <0f> 0b e9 0d f7 ff ff 48 8b 44 24 40 48 8d b8 60 08 00 00 48 89 f8 RSP: 0018:ffffc9000126f3f0 EFLAGS: 00010282 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000040000 RSI: ffffffff812bb188 RDI: fffff5200024de70 RBP: ffff88811c882a54 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffff812b4f2e R11: 0000000000000000 R12: 0000000000000000 R13: dffffc0000000000 R14: 0000000000000280 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8881f6900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000563096d39f98 CR3: 000000012cc6f000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> media_device_unregister_entity+0x41/0x70 drivers/media/mc/mc-device.c:688 dvb_media_device_free+0x1d5/0x680 drivers/media/dvb-core/dvbdev.c:226 dvb_remove_device.part.0+0x9c/0x260 drivers/media/dvb-core/dvbdev.c:568 dvb_remove_device drivers/media/dvb-core/dvbdev.c:561 [inline] dvb_unregister_device+0x1b/0x60 drivers/media/dvb-core/dvbdev.c:590 dvb_dmxdev_release+0x1c9/0x630 drivers/media/dvb-core/dmxdev.c:1460 dvb_usb_adapter_dvb_exit+0x93/0x230 drivers/media/usb/dvb-usb/dvb-usb-dvb.c:224 dvb_usb_adapter_exit drivers/media/usb/dvb-usb/dvb-usb-init.c:126 [inline] dvb_usb_exit drivers/media/usb/dvb-usb/dvb-usb-init.c:141 [inline] dvb_usb_device_exit+0x20a/0x510 drivers/media/usb/dvb-usb/dvb-usb-init.c:336 usb_unbind_interface+0x1d8/0x8e0 drivers/usb/core/driver.c:458 __device_release_driver+0x5d7/0x700 drivers/base/dd.c:1205 device_release_driver_internal drivers/base/dd.c:1236 [inline] device_release_driver+0x26/0x40 drivers/base/dd.c:1259 bus_remove_device+0x2eb/0x5a0 drivers/base/bus.c:529 device_del+0x502/0xd60 drivers/base/core.c:3581 usb_disable_device+0x35b/0x7b0 drivers/usb/core/message.c:1419 usb_disconnect.cold+0x27a/0x78e drivers/usb/core/hub.c:2225 hub_port_connect drivers/usb/core/hub.c:5197 [inline] hub_port_connect_change drivers/usb/core/hub.c:5497 [inline] port_event drivers/usb/core/hub.c:5643 [inline] hub_event+0x1c9c/0x4460 drivers/usb/core/hub.c:5725 process_one_work+0x9b2/0x1690 kernel/workqueue.c:2298 process_scheduled_works kernel/workqueue.c:2361 [inline] worker_thread+0x85c/0x11f0 kernel/workqueue.c:2447 kthread+0x40b/0x500 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 </TASK> --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot.