Subject: Re: [PATCH net-next V6 2/5] selftests: drv-net: Test XDP_PASS/DROP support

From: Martin KaFai Lau <[email-masked]>
Date: Mon, 21 Jul 2025 12:43:57 -0700

On 7/21/25 4:43 AM, Nimrod Oren wrote:
> To ensure correctness across all drivers, all direct accesses to packet
> data should use these safer helper functions instead:
> bpf_xdp_load_bytes() and bpf_xdp_store_bytes().

Not sure if the test will be run on the older kernel. fwiw, there is a 
bpf_dynptr_slice_rdwr() kfunc which was added in commit 66e3a13e7c2c.
It uses bpf_xdp_pointer() underneath, so it can avoid a copy if the requested 
data is contained in a single frag.