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

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"?

However, using this driver, with the
system suspended the device sends pause-frames as soon as the receive
buffer fills up. This produced substantial network load, up to the
point where some Ethernet switches stopped processing packets
altogether.

Using the Realtek driver (r8152) fixes this issue. Pause frames are no
longer sent while the host system is suspended.

Signed-off-by: Leon Schuermann <redacted>
Tested-by: Leon Schuermann <redacted>