On Wed, Aug 12, 2020 at 08:47:20AM +0300, M. Vefa Bicakci wrote:
On 10/08/2020 22.09, Shuah Khan wrote:
On 8/10/20 11:31 AM, Bastien Nocera wrote:
On Mon, 2020-08-10 at 19:00 +0300, M. Vefa Bicakci wrote:
Commit 88b7381a939d ("USB: Select better matching USB drivers when available") introduced the use of a "match" function to select a non-generic/better driver for a particular USB device. This unfortunately breaks the operation of usbip in general, as reported in the kernel bugzilla with bug 208267 (linked below).
Upon inspecting the aforementioned commit, one can observe that the original code in the usb_device_match function used to return 1 unconditionally, but the aforementioned commit makes the usb_device_match function use identifier tables and "match" virtual functions, if either of them are available.
Hence, this commit implements a match function for usbip that unconditionally returns true to ensure that usbip is functional again.
This change has been verified to restore usbip functionality, with a v5.7.y kernel on an up-to-date version of Qubes OS 4.0, which uses usbip to redirect USB devices between VMs.
Thanks to Jonathan Dieter for the effort in bisecting this issue down to the aforementioned commit.
Looks correct. Thanks for root causing the problem.
Reviewed-by: Bastien Nocera hadess@hadess.net
Thank you for finding and fixing the problem.
Reviewed-by: Shuah Khan skhan@linuxfoundation.org
Hello Shuah and Bastien,
Thank you for reviewing the patch!
Just to confirm, should I re-publish this patch after having added your Reviewed-by tags to the commit message? My current understanding is that a re-spin of a patch is only necessary when changes are requested during the code review. The development process documentation in the kernel repository does not mention this aspect, but I might have missed it during my quick search.
No need to resend it, my tools will pick up these reviewed-by tags and add it to the final patch when I apply it.
See the tool 'b4' if you are curious as to how that works.
thanks,
greg k-h