From: Lorenzo Bianconi <lorenzo@kernel.org>
To: Jakub Kicinski <kuba@kernel.org>
Cc: bpf@vger.kernel.org, netdev@vger.kernel.org, davem@davemloft.net,
ast@kernel.org, daniel@iogearbox.net, brouer@redhat.com,
toke@redhat.com, pabeni@redhat.com, echaudro@redhat.com,
lorenzo.bianconi@redhat.com, toshiaki.makita1@gmail.com,
andrii@kernel.org
Subject: Re: [PATCH bpf-next 2/3] veth: rework veth_xdp_rcv_skb in order to accept non-linear skb
Date: Sat, 12 Feb 2022 12:03:49 +0100 [thread overview]
Message-ID: <YgeUFb4LIP7VfeL9@lore-desk> (raw)
In-Reply-To: <20220211170414.7223ff09@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com>
[-- Attachment #1: Type: text/plain, Size: 516 bytes --]
On Feb 11, Jakub Kicinski wrote:
> On Fri, 11 Feb 2022 02:20:31 +0100 Lorenzo Bianconi wrote:
> > + if (skb_shared(skb) || skb_head_is_locked(skb)) {
>
> Is this sufficient to guarantee that the frags can be written?
> skb_cow_data() tells a different story.
Do you mean to consider paged part of the skb always not writable, right?
In other words, we should check something like:
if (skb_shared(skb) || skb_head_is_locked(skb) ||
skb_shinfo(skb)->nr_frags) {
...
}
Regards,
Lorenzo
[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 228 bytes --]
next prev parent reply other threads:[~2022-02-12 11:03 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-02-11 1:20 [PATCH bpf-next 0/3] introduce xdp frags support to veth driver Lorenzo Bianconi
2022-02-11 1:20 ` [PATCH bpf-next 1/3] net: veth: account total xdp_frame len running ndo_xdp_xmit Lorenzo Bianconi
2022-02-11 1:20 ` [PATCH bpf-next 2/3] veth: rework veth_xdp_rcv_skb in order to accept non-linear skb Lorenzo Bianconi
2022-02-12 1:04 ` Jakub Kicinski
2022-02-12 11:03 ` Lorenzo Bianconi [this message]
2022-02-14 15:48 ` Jakub Kicinski
2022-02-14 21:03 ` Lorenzo Bianconi
2022-02-11 1:20 ` [PATCH bpf-next 3/3] veth: allow jumbo frames in xdp mode Lorenzo Bianconi
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=YgeUFb4LIP7VfeL9@lore-desk \
--to=lorenzo@kernel.org \
--cc=andrii@kernel.org \
--cc=ast@kernel.org \
--cc=bpf@vger.kernel.org \
--cc=brouer@redhat.com \
--cc=daniel@iogearbox.net \
--cc=davem@davemloft.net \
--cc=echaudro@redhat.com \
--cc=kuba@kernel.org \
--cc=lorenzo.bianconi@redhat.com \
--cc=netdev@vger.kernel.org \
--cc=pabeni@redhat.com \
--cc=toke@redhat.com \
--cc=toshiaki.makita1@gmail.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;
as well as URLs for NNTP newsgroup(s).