From: Zaremba, Larysa <[email protected]>
Date: Tue, 17 Feb 2026 14:24:45 +0100
> The only user of frag_size field in XDP RxQ info is
> bpf_xdp_frags_increase_tail(). It clearly expects whole buffer size instead
> of DMA write size. Different assumptions in idpf driver configuration lead
> to negative tailroom.
>
> To make it worse, buffer sizes are not actually uniform in idpf when
> splitq is enabled, as there are several buffer queues, so rxq->rx_buf_size
> is meaningless in this case.
>
> Use truesize of the first bufq in AF_XDP ZC, as there is only one. Disable
> growinf tail for regular splitq.
>
> Fixes: ac8a861f632e ("idpf: prepare structures to support XDP")
> Signed-off-by: Larysa Zaremba <[email protected]>
Acked-by: Alexander Lobakin <[email protected]>
Thanks for handling this!
Olek