Re: [PATCH net-next 2/2] net: stmmac: disable TX checksum offload for jumbo frames on bugged cores

[Paolo Abeni <pabeni@redhat.com>]

On 10/13/26 17:33, Lorenzo Bianconi wrote:
>> Thank you for your contribution! Sashiko AI review found more severe
>> issue(s) in other patches of this series. This mail is only an FYI, in case
>> you want to address the nit picks below when you respin.
>>
>> Low priority / nit picks for your consideration:
>>
>> - [Low] The commit message's premise doesn't match the tree.
>>
>> Pre-existing issues:
>> - [Medium] This problem wasn't introduced by this patch, but
>>    stmmac_xdp_xmit_xdpf() never looks at priv->plat->tx_coe when deciding…
>>
>> --
>>
>> net: stmmac: disable TX checksum offload for jumbo frames on bugged cores
>>
>> This patch turns off TX checksum insertion in stmmac_xdp_xmit_xdpf() for
>> frames longer than ETH_FRAME_LEN on bugged_jumbo cores. It is meant to
>> match the stmmac_fix_features() workaround that the skb path already uses.
>>
>>> The XDP TX
>>> path bypasses that workaround, so once XDP is allowed at MTU >
>>> ETH_DATA_LEN, jumbo frames sent via XDP_TX or redirected into the
>>> device would leave the interface with a full checksum insertion enabled
>>> on those cores - exactly what the workaround is meant to avoid.
>>
>> [Severity: Low]
>> Can this scenario happen in the current tree? XDP still can't be used with
>> a jumbo MTU. stmmac_xdp_set_prog() refuses to attach a program when the MTU
>> is above ETH_DATA_LEN:
> 
> This is actually a preliminary fix needed to remove the MTU limitation when the
> device is running in XDP mode.
The point is that this patch does not address any issues, no it should not
include a fixes tag. I'll drop it while applying the series.

Also a more explicative cover letter would have helped.

No need to repost.

Thanks,

Paolo