From: Simon Horman <horms@kernel.org>
To: Dimitri Daskalakis <dimitri.daskalakis1@gmail.com>
Cc: "David S . Miller" <davem@davemloft.net>,
Alexander Duyck <alexanderduyck@fb.com>,
Jakub Kicinski <kuba@kernel.org>,
Eric Dumazet <edumazet@google.com>,
Paolo Abeni <pabeni@redhat.com>,
Andrew Lunn <andrew+netdev@lunn.ch>,
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>,
Mohsin Bashir <mohsin.bashr@gmail.com>,
netdev@vger.kernel.org, bpf@vger.kernel.org,
linux-kselftest@vger.kernel.org
Subject: Re: [PATCH net] eth: fbnic: Add validation for MTU changes
Date: Mon, 16 Feb 2026 12:18:51 +0000 [thread overview]
Message-ID: <aZMLK7CVV6hSbUOg@horms.kernel.org> (raw)
In-Reply-To: <20260214171949.772493-1-dimitri.daskalakis1@gmail.com>
On Sat, Feb 14, 2026 at 09:19:49AM -0800, Dimitri Daskalakis wrote:
> Increasing the MTU beyond the HDS threshold causes the hardware to
> fragment packets across multiple buffers. If a single-buffer XDP program
> is attached, the driver will drop all multi-frag frames. While we can't
> prevent a remote sender from sending non-TCP packets larger than the MTU,
> this will prevent users from inadvertently breaking new TCP streams.
>
> Traditionally, drivers supported XDP with MTU less than 4Kb
> (packet per page). Fbnic currently prevents attaching XDP when MTU is too high.
> But it does not prevent increasing MTU after XDP is attached.
>
> Fixes: 1b0a3950dbd4 ("eth: fbnic: Add XDP pass, drop, abort support")
> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
> Signed-off-by: Dimitri Daskalakis <dimitri.daskalakis1@gmail.com>
Reviewed-by: Simon Horman <horms@kernel.org>
next prev parent reply other threads:[~2026-02-16 12:18 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-02-14 17:19 [PATCH net] eth: fbnic: Add validation for MTU changes Dimitri Daskalakis
2026-02-16 12:18 ` Simon Horman [this message]
2026-02-18 6:33 ` 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=aZMLK7CVV6hSbUOg@horms.kernel.org \
--to=horms@kernel.org \
--cc=alexanderduyck@fb.com \
--cc=andrew+netdev@lunn.ch \
--cc=ast@kernel.org \
--cc=bpf@vger.kernel.org \
--cc=daniel@iogearbox.net \
--cc=davem@davemloft.net \
--cc=dimitri.daskalakis1@gmail.com \
--cc=edumazet@google.com \
--cc=hawk@kernel.org \
--cc=john.fastabend@gmail.com \
--cc=kuba@kernel.org \
--cc=linux-kselftest@vger.kernel.org \
--cc=mohsin.bashr@gmail.com \
--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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.