During file transfer, canceling the transfer in pc will cause a kernel crash

[guoweilkd]

Operation steps：

1. run umtprd-ffs.sh
2. Wait for Explorer to pop up in Windows 10
3. copy file from board to win10
4. Click Cancel to close the copy dialog box during the copy process in Windows 10
5. kernel crash
   
   Below is the packet captured by wireshark
   wireshark_usb_cap.zip

[jfdelnero]

The kernel crash because the umtprd is blocked into a read function while the kernel is killing the link. i think that this will need a major rewrite of the low level layer to fix this. it appears that async api seems the way to go.

[guoweilkd]

Is this a known bug? Does your 'low level layer' refer to the UDC layer? Are there any examples that have been implemented? thanks

[guoweilkd]

It seems to be a bug caused by UDC driver. It works normally after modification.

[jfdelnero]

Which modification ? @guoweilkd