Hello, syzbot has tested the proposed patch but the reproducer still triggered crash: WARNING in usbhid_stop usb 2-1: USB disconnect, device number 5 ------------[ cut here ]------------ usbhid 2-1:0.0: Stop while open (alloc = 1) WARNING: CPU: 0 PID: 12 at drivers/hid/usbhid/hid-core.c:1210 usbhid_stop+0x156/0x610 drivers/hid/usbhid/hid-core.c:1210 Kernel panic - not syncing: panic_on_warn set ... CPU: 0 PID: 12 Comm: kworker/0:1 Not tainted 5.6.0-rc7-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: usb_hub_wq hub_event Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0xef/0x16e lib/dump_stack.c:118 panic+0x2aa/0x6e1 kernel/panic.c:221 __warn.cold+0x2f/0x30 kernel/panic.c:582 report_bug+0x27b/0x2f0 lib/bug.c:195 fixup_bug arch/x86/kernel/traps.c:174 [inline] fixup_bug arch/x86/kernel/traps.c:169 [inline] do_error_trap+0x12b/0x1e0 arch/x86/kernel/traps.c:267 do_invalid_op+0x32/0x40 arch/x86/kernel/traps.c:286 invalid_op+0x23/0x30 arch/x86/entry/entry_64.S:1027 RIP: 0010:usbhid_stop+0x156/0x610 drivers/hid/usbhid/hid-core.c:1210 Code: 48 89 7c 24 08 e8 ea c4 bd fc 48 8b 7c 24 08 e8 10 95 f7 fd 48 8b 14 24 44 89 f9 48 c7 c7 80 45 84 86 48 89 c6 e8 92 55 92 fc <0f> 0b e8 c3 c4 bd fc 48 8d bd ac 1e 00 00 48 b8 00 00 00 00 00 fc RSP: 0018:ffff8881da227640 EFLAGS: 00010282 RAX: 0000000000000000 RBX: ffff8881d8b48000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff812974dd RDI: ffffed103b444eba RBP: ffff8881c7710000 R08: ffff8881da211880 R09: ffffed103b64439f R10: ffffed103b64439e R11: ffff8881db221cf3 R12: ffff8881c54b0000 R13: ffff8881d8b4a9a8 R14: ffff8881c7711fd8 R15: 0000000000000001 wacom_remove+0x88/0x3b0 drivers/hid/wacom_sys.c:2772 hid_device_remove+0xed/0x240 drivers/hid/hid-core.c:2296 __device_release_driver drivers/base/dd.c:1135 [inline] device_release_driver_internal+0x231/0x500 drivers/base/dd.c:1168 bus_remove_device+0x2eb/0x5a0 drivers/base/bus.c:533 device_del+0x481/0xd30 drivers/base/core.c:2677 hid_remove_device drivers/hid/hid-core.c:2467 [inline] hid_destroy_device+0xe1/0x150 drivers/hid/hid-core.c:2486 usbhid_disconnect+0x9f/0xe0 drivers/hid/usbhid/hid-core.c:1426 usb_unbind_interface+0x1bd/0x8a0 drivers/usb/core/driver.c:436 __device_release_driver drivers/base/dd.c:1137 [inline] device_release_driver_internal+0x42f/0x500 drivers/base/dd.c:1168 bus_remove_device+0x2eb/0x5a0 drivers/base/bus.c:533 device_del+0x481/0xd30 drivers/base/core.c:2677 usb_disable_device+0x23d/0x790 drivers/usb/core/message.c:1238 usb_disconnect+0x293/0x900 drivers/usb/core/hub.c:2211 hub_port_connect drivers/usb/core/hub.c:5046 [inline] hub_port_connect_change drivers/usb/core/hub.c:5335 [inline] port_event drivers/usb/core/hub.c:5481 [inline] hub_event+0x1a1d/0x4300 drivers/usb/core/hub.c:5563 process_one_work+0x94b/0x1620 kernel/workqueue.c:2266 worker_thread+0x96/0xe20 kernel/workqueue.c:2412 kthread+0x318/0x420 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Kernel Offset: disabled Rebooting in 86400 seconds.. Tested on: commit: 0fa84af8 Merge tag 'usb-serial-5.7-rc1' of https://git.ker.. git tree: https://github.com/google/kasan.git console output: https://syzkaller.appspot.com/x/log.txt?x=12dbb8f7e00000 kernel config: https://syzkaller.appspot.com/x/.config?x=6b9c154b0c23aecf dashboard link: https://syzkaller.appspot.com/bug?extid=7bf5a7b0f0a1f9446f4c compiler: gcc (GCC) 9.0.0 20181231 (experimental) patch: https://syzkaller.appspot.com/x/patch.diff?x=105bb8f7e00000
