Re: [PATCH bpf v4 0/9] Address XDP frags having negative tailroom

From: Jakub Kicinski

Date: Wed Mar 04 2026 - 21:56:01 EST


On Mon, 2 Mar 2026 17:17:13 +0100 Larysa Zaremba wrote:
> Aside from the issue described below, tailroom calculation does not account
> for pages being split between frags, e.g. in i40e, enetc and
> AF_XDP ZC with smaller chunks. These series address the problem by
> calculating modulo (skb_frag_off() % rxq->frag_size) in order to get
> data offset within a smaller block of memory. Please note, xskxceiver
> tail grow test passes without modulo e.g. in xdpdrv mode on i40e,
> because there is not enough descriptors to get to flipped buffers.

This was re-assigned to netdev in pw, I presume by BPF maintainers.
But it doesn't apply to net. There's a conflict in ice.
Could you rebase on net and repost?