Re: [PATCH net-next 1/5] net: ethtool: only allow set_rxnfc with rss + ring_cookie if driver opts in

[Edward Cree <ecree.xilinx@gmail.com>]

On 25/11/2024 14:20, Ahmed Zaki wrote:
> On 2024-11-25 7:10 a.m., Gal Pressman wrote:
>> On 25/11/2024 15:21, Edward Cree wrote:
>>> Also, the check below it, dealing with sym-xor, looks like it's only
>>>   relevant to ETHTOOL_SRXFH, since info.data is garbage for other commands.
>>>   Ahmed, is my understanding correct there?
>>>
>>
>> Speaking of the below check, the sanity check depends on the order of
>> operations, for example:
>> 1. Enable symmetric xor
>> 2. Request hash on src only
>> = Error as expected, however:
> 
> Correct. The check below is to make sure that no ntuple that does not cover symmetric fields is added if symm-xor is enabled.
But symm-xor is about hashing, and is only relevant to traffic being
 directed by RSS.  The user should still be allowed to, and the NIC
 should be able to handle, setting an ntuple filter (SRXCLSRLINS)
 that is asymmetric, to override the symmetric hashing for selected
 traffic.
symm-xor should only constrain RXFH settings.  And in fact even if
 you wanted to block asymm ntuple filters, the current code does not
 do that, since the info.data fields it looks at aren't populated for
 ntuple filters (whose filter fields are defined by info.fs).
So the xfrm check should be under `if (info.cmd == ETHTOOL_SRXFH)`.