Re: [PATCH bpf-next v3 1/5] netlink: specs: Add XDP RX checksum capability to XDP metadata specs
From: Jakub Kicinski <kuba@kernel.org>
Date: 2026-02-19 01:47:44
Also in:
bpf, intel-wired-lan, linux-kselftest
On Tue, 17 Feb 2026 09:33:56 +0100 Lorenzo Bianconi wrote:
+ * In case of success, ``ip_summed`` is set to the RX checksum result. Possible + * values are: + * ``XDP_CHECKSUM_NONE`` + * ``XDP_CHECKSUM_UNNECESSARY`` + * ``XDP_CHECKSUM_COMPLETE`` + * + * In case of success, ``cksum_meta`` contains the hw computed checksum value + * for ``XDP_CHECKSUM_COMPLETE`` or the ``csum_level`` for + * ``XDP_CHECKSUM_UNNECESSARY``. It is set to 0 for ``XDP_CHECKSUM_NONE``
It's fairly common for NICs to report both csum complete and unnecessary. Which one should the driver return in that case? What if the user prefers the other one?..