On Tuesday, July 8, 2025 10:18 AM, Jakub Kicinski <kuba@kernel.org> wrote:
>On Tue, 8 Jul 2025 02:06:11 +0000 Song, Yoong Siang wrote:
>>> Why would the driver need to move it back?
>>> On XDP_PASS an skb is constructed, so the metadata should
>>> be transferred to the skb. There is no need to copy it back
>>> as a prepend.
>>
>> I said so because I thought need to put back the timestamp
>> as prepend and then point skb_shared_hwtstamps.netdev_data to it
>> to support the ndo_get_tstamp().
>
>No need, the timestamps are set in shared info directly.
>There are multiple drivers which use the metadata prepend
>method, so I'm pretty sure it should work.

Thanks for pointing me in the right direction.
I'll proceed with updating the IGC driver and conduct tests
to ensure everything works as expected.