[Intel-wired-lan] [TEST] Weird RSS state on ice

[Intel-wired-lan] [TEST] Weird RSS state on ice

[Jakub Kicinski]

Hi!

I noticed in the netdev CI that the ice runner fails to run the
toeplitz tests because of the RSS config.

https://netdev-ci-results.intel.com/ice-results/net-next-hw-2026-06-23--00-00/ice-E810-CQ2/toeplitz.py/stdout

I added some extra debug on the branch:

net.lib.ynl.pyynl.lib.ynl.NlError: Netlink error: hash field config is not symmetric 16 304: Invalid argument {'bad-attr': '.input-xfrm'}

16, 304 means GTP flow, GTP_TEID field. So we are trying to disable
symmetric RSS, but the field configuration contains TEID. The problem
is this is an illegal configuration in the first place. We are
_disabling_ symmetric RSS, but the kernel tries to make sure that both
before and after states are correct (because the configuration involves
multiple calls to the drivers and may fail half-way-thru). If the
current config is illegal net/ethtool/ won't even let us restore it to
sane state.

So the question is how we got into this state. It does not happen
on netdev machines. And on Intel machines it happens randomly around
30% of the time.

I tried to look thru the driver code and I don't see how we could end
up with such a config.

Could y'all have a look and figure out / fix this? This has been
happening for a while back but I was waiting until the merge window 
to poke at it first.