From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 29110352C2E; Fri, 13 Feb 2026 10:40:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770979230; cv=none; b=mfSOSMiMkk1Z+xmrEYS8eag/fBaavLLCkeHsTwq26WPSifNE7dnm2ZWq6yoOQus9tiY8n7phy1zSvRp04/NhX2cPA/6JDcMFLwsUemyrmp7B12shHZJF7J+8946Sdj8Axi1x8IgFieGiK/BSjEBbPomoEKG+Z6GNbAGa21l81Sg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770979230; c=relaxed/simple; bh=SC2ovmnTmN31BJMgWSDQstBBBIerODPENfDec9d9YDM=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=I3ZlsLbtYmkKdh4m8BaK91ryObnUi74AvjEDIGC4Arc5t3g1MblYyLhHsJ+ovyDVqNrqL0hRB/M7BejbORDK8xGFvSYtY8aipVYjTpaPAsSlHkTz/+peH3jlbiOO+TZs+giIRQV8tddFnfBO23PWyDAZCPhltdE+OSlLsMX4aZE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=mAdbZlLl; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="mAdbZlLl" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 15CD8C116C6; Fri, 13 Feb 2026 10:40:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1770979229; bh=SC2ovmnTmN31BJMgWSDQstBBBIerODPENfDec9d9YDM=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=mAdbZlLlE2sYlveU4i9kF08qSHcQUHP3CpPs4Zj5+WqKzalKAeEPuvX3K6k4peRql gMK+S09NxnEhq0iJwR0aCKlws6UHTq3w2hQIQ84G2TlbZpnYApfNxmGSSMCa0CNrBs 2S0ZMe2kAWouyXlIlaffTcNyEdDn7SzDB89hFurup7S6g/iBz0nuX0VImNEJtXP0Mu TqpfuXbE+xaDpMelpayQ7cAy4ED9vDGY53FTrfuHKvlFRl+MBlZB4jBii+bv/KMlmf 2RSUbDfzvtovAQ8+N0BuOxsMz+P/ZEDFUGYQun0kN+scYNscoHdeboWsYY1hPMBzN3 yT5cvSKD0p3VA== Date: Fri, 13 Feb 2026 11:40:27 +0100 From: Lorenzo Bianconi To: Stanislav Fomichev Cc: Donald Hunter , Jakub Kicinski , "David S. Miller" , Eric Dumazet , Paolo Abeni , Simon Horman , Alexei Starovoitov , Daniel Borkmann , Jesper Dangaard Brouer , John Fastabend , Stanislav Fomichev , Andrew Lunn , Tony Nguyen , Przemek Kitszel , Alexander Lobakin , Andrii Nakryiko , Martin KaFai Lau , Eduard Zingerman , Song Liu , Yonghong Song , KP Singh , Hao Luo , Jiri Olsa , Shuah Khan , Maciej Fijalkowski , Jakub Sitnicki , netdev@vger.kernel.org, bpf@vger.kernel.org, intel-wired-lan@lists.osuosl.org, linux-kselftest@vger.kernel.org Subject: Re: [PATCH bpf-next 1/5] netlink: specs: Add XDP RX checksum capability to XDP metadata specs Message-ID: References: <20260210-bpf-xdp-meta-rxcksum-v1-0-e5d55caa0541@kernel.org> <20260210-bpf-xdp-meta-rxcksum-v1-1-e5d55caa0541@kernel.org> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="qwJIGiRKX8fs1N5o" Content-Disposition: inline In-Reply-To: --qwJIGiRKX8fs1N5o Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Feb 12, Stanislav Fomichev wrote: > On 02/10, Lorenzo Bianconi wrote: > > Introduce XDP RX checksum capability to XDP metadata specs. XDP RX > > checksum will be use by devices capable of exposing receive checksum > > result via bpf_xdp_metadata_rx_checksum(). > > Moreover, introduce xmo_rx_checksum netdev callback in order allow the > > eBPF program bounded to the device to retrieve the RX checksum result > > computed by the hw NIC. > >=20 > > Signed-off-by: Lorenzo Bianconi > > --- > > Documentation/netlink/specs/netdev.yaml | 5 +++++ > > include/net/xdp.h | 14 ++++++++++++++ > > include/uapi/linux/netdev.h | 3 +++ > > net/core/xdp.c | 29 +++++++++++++++++++++++++= ++++ > > tools/include/uapi/linux/netdev.h | 3 +++ > > 5 files changed, 54 insertions(+) > >=20 > > diff --git a/Documentation/netlink/specs/netdev.yaml b/Documentation/ne= tlink/specs/netdev.yaml > > index 596c306ce52b8303b20680ff0cd34d4fd9db0e48..58eda634668a07860447a65= d9fc2284839af6244 100644 > > --- a/Documentation/netlink/specs/netdev.yaml > > +++ b/Documentation/netlink/specs/netdev.yaml > > @@ -61,6 +61,11 @@ definitions: > > doc: | > > Device is capable of exposing receive packet VLAN tag via > > bpf_xdp_metadata_rx_vlan_tag(). > > + - > > + name: checksum > > + doc: | > > + Device is capable of exposing receive checksum result via > > + bpf_xdp_metadata_rx_checksum(). > > - > > type: flags > > name: xsk-flags > > diff --git a/include/net/xdp.h b/include/net/xdp.h > > index aa742f413c358575396530879af4570dc3fc18de..9ab9ac10ae2074b70618a9d= 4f32544d8b9a30b63 100644 > > --- a/include/net/xdp.h > > +++ b/include/net/xdp.h > > @@ -586,6 +586,10 @@ void xdp_attachment_setup(struct xdp_attachment_in= fo *info, > > NETDEV_XDP_RX_METADATA_VLAN_TAG, \ > > bpf_xdp_metadata_rx_vlan_tag, \ > > xmo_rx_vlan_tag) \ > > + XDP_METADATA_KFUNC(XDP_METADATA_KFUNC_RX_CHECKSUM, \ > > + NETDEV_XDP_RX_METADATA_CHECKSUM, \ > > + bpf_xdp_metadata_rx_checksum, \ > > + xmo_rx_checksum) > > =20 > > enum xdp_rx_metadata { > > #define XDP_METADATA_KFUNC(name, _, __, ___) name, > > @@ -643,12 +647,22 @@ enum xdp_rss_hash_type { > > XDP_RSS_TYPE_L4_IPV6_SCTP_EX =3D XDP_RSS_TYPE_L4_IPV6_SCTP | XDP_RSS_= L3_DYNHDR, > > }; > > =20 > > +enum xdp_checksum { > > + XDP_CHECKSUM_NONE =3D CHECKSUM_NONE, > > + XDP_CHECKSUM_UNNECESSARY =3D CHECKSUM_UNNECESSARY, > > + XDP_CHECKSUM_COMPLETE =3D CHECKSUM_COMPLETE, > > + XDP_CHECKSUM_PARTIAL =3D CHECKSUM_PARTIAL, > > +}; > > + > > struct xdp_metadata_ops { > > int (*xmo_rx_timestamp)(const struct xdp_md *ctx, u64 *timestamp); > > int (*xmo_rx_hash)(const struct xdp_md *ctx, u32 *hash, > > enum xdp_rss_hash_type *rss_type); > > int (*xmo_rx_vlan_tag)(const struct xdp_md *ctx, __be16 *vlan_proto, > > u16 *vlan_tci); > > + int (*xmo_rx_checksum)(const struct xdp_md *ctx, > > + enum xdp_checksum *ip_summed, > > + u32 *cksum_meta); > > }; > > =20 > > #ifdef CONFIG_NET > > diff --git a/include/uapi/linux/netdev.h b/include/uapi/linux/netdev.h > > index e0b579a1df4f2126acec6c44c299e97bbbefe640..d20da430cfd57bc26b5ea2f= 406c27b48d8a81693 100644 > > --- a/include/uapi/linux/netdev.h > > +++ b/include/uapi/linux/netdev.h > > @@ -47,11 +47,14 @@ enum netdev_xdp_act { > > * hash via bpf_xdp_metadata_rx_hash(). > > * @NETDEV_XDP_RX_METADATA_VLAN_TAG: Device is capable of exposing rec= eive > > * packet VLAN tag via bpf_xdp_metadata_rx_vlan_tag(). > > + * @NETDEV_XDP_RX_METADATA_CHECKSUM: Device is capable of exposing rec= eive > > + * checksum result via bpf_xdp_metadata_rx_checksum(). > > */ > > enum netdev_xdp_rx_metadata { > > NETDEV_XDP_RX_METADATA_TIMESTAMP =3D 1, > > NETDEV_XDP_RX_METADATA_HASH =3D 2, > > NETDEV_XDP_RX_METADATA_VLAN_TAG =3D 4, > > + NETDEV_XDP_RX_METADATA_CHECKSUM =3D 8, > > }; > > =20 > > /** > > diff --git a/net/core/xdp.c b/net/core/xdp.c > > index fee6d080ee85fc2d278bfdddfd1365633058ec06..e51346ad3031f28d11c11f8= 205da6cd954da82de 100644 > > --- a/net/core/xdp.c > > +++ b/net/core/xdp.c > > @@ -961,6 +961,35 @@ __bpf_kfunc int bpf_xdp_metadata_rx_vlan_tag(const= struct xdp_md *ctx, > > return -EOPNOTSUPP; > > } > > =20 > > +/** > > + * bpf_xdp_metadata_rx_checksum - Read XDP frame RX checksum. > > + * @ctx: XDP context pointer. > > + * @ip_summed: Return value pointer indicating checksum result. > > + * @cksum_meta: Return value pointer indicating checksum result metada= ta. > > + * > > + * 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`` > > + * ``XDP_CHECKSUM_PARTIAL`` > > + * > > + * In case of success, ``cksum_meta`` contains the hw computed checksu= m value > > + * for ``XDP_CHECKSUM_COMPLETE`` or the ``csum_level`` for > > + * ``XDP_CHECKSUM_UNNECESSARY``. It is set to 0 for ``XDP_CHECKSUM_NON= E`` and > > + * ``XDP_CHECKSUM_PARTIAL``. > > + * > > + * Return: > > + * * Returns 0 on success or ``-errno`` on error. > > + * * ``-EOPNOTSUPP`` : means device driver does not implement kfunc > > + * * ``-ENODATA`` : means no RX-timestamp available for this frame > > + */ > > +__bpf_kfunc int bpf_xdp_metadata_rx_checksum(const struct xdp_md *ctx, > > + u8 *ip_summed, u32 *cksum_meta) > > +{ >=20 > Any reason not to do enum xdp_checksum *ip_summed here as well? ack, I will fix it in v2. Regards, Lorenzo --qwJIGiRKX8fs1N5o Content-Type: application/pgp-signature; name=signature.asc -----BEGIN PGP SIGNATURE----- iHUEABYKAB0WIQTquNwa3Txd3rGGn7Y6cBh0uS2trAUCaY7/mwAKCRA6cBh0uS2t rPcoAQCb7m6pbv19sIu76bYil26EtBbnmmstPmm4RPxwfLKneAEA63LE9ex6Lo4S bBOpGzrQF7VzBTabcYLSnAVzI5jkiQI= =YHsg -----END PGP SIGNATURE----- --qwJIGiRKX8fs1N5o--