From: Jakub Kicinski <kuba@kernel.org>
To: Jiayuan Chen <jiayuan.chen@linux.dev>
Cc: netdev@vger.kernel.org, "Kenneth Lee" <kennethbwlee@snu.ac.kr>,
"David S. Miller" <davem@davemloft.net>,
"Eric Dumazet" <edumazet@google.com>,
"Paolo Abeni" <pabeni@redhat.com>,
"Simon Horman" <horms@kernel.org>,
"Alexei Starovoitov" <ast@kernel.org>,
"Daniel Borkmann" <daniel@iogearbox.net>,
"Jesper Dangaard Brouer" <hawk@kernel.org>,
"John Fastabend" <john.fastabend@gmail.com>,
"Stanislav Fomichev" <sdf@fomichev.me>,
"Kuniyuki Iwashima" <kuniyu@google.com>,
"Hangbin Liu" <liuhangbin@gmail.com>,
"Krishna Kumar" <krikku@gmail.com>,
"Martin Karsten" <mkarsten@uwaterloo.ca>,
"Toke Høiland-Jørgensen" <toke@redhat.com>,
"Martin Willi" <martin@strongswan.org>,
linux-kernel@vger.kernel.org, bpf@vger.kernel.org
Subject: Re: [PATCH net-next] net: xdp: don't assume an Ethernet header in generic XDP
Date: Fri, 14 Aug 2026 14:09:52 -0700 [thread overview]
Message-ID: <20260814140952.12d3f43f@kernel.org> (raw)
In-Reply-To: <20260813113229.381136-1-jiayuan.chen@linux.dev>
On Thu, 13 Aug 2026 19:32:24 +0800 Jiayuan Chen wrote:
> Refusing to attach XDP to L3 devices instead would not help: mac_len is a
> property of the skb, not of the netdev, so an ARPHRD_ETHER device can see
> mac_len == 0 too.
Let's try. There is no native XDP on any non-ether device, making
generic xdp work on those is silly. Just attach the BPF in TC.
AI says that one example for mac_len=0 packet on ether device is IP
mcast loopback, which should not go via generic XDP in the first place.
> Fixes: 22b6034323fd ("net, xdp: Update pkt_type if generic XDP changes unicast MAC")
Please don't send fixes to net-next :|
--
pw-bot: cr
prev parent reply other threads:[~2026-08-14 21:09 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-08-13 11:32 [PATCH net-next] net: xdp: don't assume an Ethernet header in generic XDP Jiayuan Chen
2026-08-14 21:09 ` Jakub Kicinski [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20260814140952.12d3f43f@kernel.org \
--to=kuba@kernel.org \
--cc=ast@kernel.org \
--cc=bpf@vger.kernel.org \
--cc=daniel@iogearbox.net \
--cc=davem@davemloft.net \
--cc=edumazet@google.com \
--cc=hawk@kernel.org \
--cc=horms@kernel.org \
--cc=jiayuan.chen@linux.dev \
--cc=john.fastabend@gmail.com \
--cc=kennethbwlee@snu.ac.kr \
--cc=krikku@gmail.com \
--cc=kuniyu@google.com \
--cc=linux-kernel@vger.kernel.org \
--cc=liuhangbin@gmail.com \
--cc=martin@strongswan.org \
--cc=mkarsten@uwaterloo.ca \
--cc=netdev@vger.kernel.org \
--cc=pabeni@redhat.com \
--cc=sdf@fomichev.me \
--cc=toke@redhat.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox