From: Stanislav Fomichev <sdf.kernel@gmail.com>
To: Jakub Kicinski <kuba@kernel.org>
Cc: davem@davemloft.net, netdev@vger.kernel.org, edumazet@google.com,
pabeni@redhat.com, andrew+netdev@lunn.ch, horms@kernel.org,
daniel@iogearbox.net, hawk@kernel.org, john.fastabend@gmail.com,
sdf@fomichev.me, ap420073@gmail.com, bpf@vger.kernel.org
Subject: Re: [PATCH net] net: make dev_xdp_sb_prog_count() see programs attached through a link
Date: Thu, 1 Oct 2026 10:04:53 -0700 [thread overview]
Message-ID: <ar6SryEPDgA25zKA@devvm7509.cco0.facebook.com> (raw)
In-Reply-To: <20261001012559.297751-1-kuba@kernel.org>
On 09/30, Jakub Kicinski wrote:
> ethtool refuses to enable tcp-data-split on a device running
> a single-buffer XDP program (which can't deal with the payload
> landing in a separate buffer). dev_xdp_sb_prog_count() only looks
> at xdp_state[].prog though, ignoring bpf_link integration.
> Get the prog pointer from dev_xdp_prog(), which will consult both.
>
> bpf_xdp_link_update() needs a bit of a touch-up, too, since
> ethtool calls dev_xdp_sb_prog_count() with just the instance
> lock (for ops-locked devices) - we now have to make sure the
> link updates happen under that lock.
>
> Spotted by AI while reviewing the XDP propagation series,
> verified and tested on netdevsim with a C test along these lines:
>
> link = bpf_program__attach_xdp(prog, ifindex);
> system("ethtool -G eth0 tcp-data-split on")
>
> Fixes: 197258f0ef68 ("net: ethtool: add hds_config member in ethtool_netdev_state")
> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
next prev parent reply other threads:[~2026-10-01 17:05 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-10-01 1:25 [PATCH net] net: make dev_xdp_sb_prog_count() see programs attached through a link Jakub Kicinski
2026-10-01 17:04 ` Stanislav Fomichev [this message]
2026-10-05 22:10 ` patchwork-bot+netdevbpf
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=ar6SryEPDgA25zKA@devvm7509.cco0.facebook.com \
--to=sdf.kernel@gmail.com \
--cc=andrew+netdev@lunn.ch \
--cc=ap420073@gmail.com \
--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=john.fastabend@gmail.com \
--cc=kuba@kernel.org \
--cc=netdev@vger.kernel.org \
--cc=pabeni@redhat.com \
--cc=sdf@fomichev.me \
/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