On Sat, 09 Jan 2021 10:39:27 +0100 Leon Schuermann wrote:

Jakub Kicinski [off-list ref] writes:

quoted

On Fri,  8 Jan 2021 21:27:27 +0100 Leon Schuermann wrote:  

quoted

This USB-C Hub (17ef:721e) based on the Realtek RTL8153B chip used to
work with the cdc_ether driver.  

When you say "used to work" do you mean there was a regression where
the older kernels would work fine and newer don't? Or just "it works
most of the time"?  

Sorry, I should've clarified that. "Used to work" is supposed to say
"the device used the generic cdc_ether driver", as in

[  +0.000004] usb 4-1.1: Product: Lenovo Powered Hub
[  +0.000003] usb 4-1.1: Manufacturer: Lenovo
[  +0.000002] usb 4-1.1: SerialNumber: xxxxxxxxx
[  +0.024803] cdc_ether 4-1.1:2.0 eth0: register 'cdc_ether' at
              usb-0000:2f:00.0-1.1, CDC Ethernet Device,
              xx:xx:xx:xx:xx:xx

I guess it did technically work correctly, except for the reported issue
when the host system suspends, which is fixed by using the dedicated
Realtek driver. As far as I know this hasn't been fixed before, so it's
not a regression.

I see. In the last release cycle there were patches for allowing
cdc_ether to drive RTL8153 devices when r8152 is not available. 
I wanted to double check with you that nothing changed here,
that's to say that the cdc_ether is not used even if r8152 is 
built after an upgrade to 5.11-rc.

Should I update the commit message accordingly? Thanks!

Yes please, otherwise backporters may be confused about how 
to classify this change.