netdev - Re: [PATCH bpf-next v3 3/4] xdp: recycle Page Pool backed skbs built from XDP frames

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date:   Fri, 17 Mar 2023 14:36:23 +0100
From:   Alexander Lobakin <aleksander.lobakin@...el.com>
To:     Jesper Dangaard Brouer <jbrouer@...hat.com>
CC:     <brouer@...hat.com>, Alexei Starovoitov <ast@...nel.org>,
        Daniel Borkmann <daniel@...earbox.net>,
        Andrii Nakryiko <andrii@...nel.org>,
        Martin KaFai Lau <martin.lau@...ux.dev>,
        Maciej Fijalkowski <maciej.fijalkowski@...el.com>,
        Larysa Zaremba <larysa.zaremba@...el.com>,
        Toke Høiland-Jørgensen <toke@...hat.com>,
        Song Liu <song@...nel.org>,
        Jesper Dangaard Brouer <hawk@...nel.org>,
        John Fastabend <john.fastabend@...il.com>,
        Menglong Dong <imagedong@...cent.com>,
        "Mykola Lysenko" <mykolal@...com>,
        "David S. Miller" <davem@...emloft.net>,
        "Jakub Kicinski" <kuba@...nel.org>,
        Eric Dumazet <edumazet@...gle.com>,
        Paolo Abeni <pabeni@...hat.com>, <bpf@...r.kernel.org>,
        <netdev@...r.kernel.org>, <linux-kernel@...r.kernel.org>,
        Freysteinn Alfredsson <Freysteinn.Alfredsson@....se>
Subject: Re: [PATCH bpf-next v3 3/4] xdp: recycle Page Pool backed skbs built
 from XDP frames

From: Jesper Dangaard Brouer <jbrouer@...hat.com>
Date: Thu, 16 Mar 2023 18:10:26 +0100

> 
> On 15/03/2023 15.58, Alexander Lobakin wrote:
>> From: Jesper Dangaard Brouer <jbrouer@...hat.com>
>> Date: Wed, 15 Mar 2023 15:55:44 +0100

[...]

> Thanks for signing up for fixing these issues down-the-road :-)

At some point, I wasn't sure which commit tags to put to Fixes:. Like,
from one PoV, it's not my patch which introduced them. From the other
side, there was no chance to have 0x42 overwritten in the metadata
during the selftest before that switch and no one could even predict it
(I didn't expect XDP_PASS frames from the test_run to reach neigh xmit
at all), so the original code is not buggy itself as well ._.

> 
> For what is it worth, I've rebased to include this patchset on my
> testlab.
> 
> For now, I've tested mlx5 with cpumap redirect and net stack processing,
> everything seems to be working nicely. When disabling GRO/GRO, then the
> cpumap get same and sometimes better TCP throughput performance,
> even-though checksum have to be done in software. (Hopefully we can soon
> close the missing HW checksum gap with XDP-hints).

Yeah I'm also looking forward to having some hints being passed to
cpumap/veth, so that __xdp_build_skb_from_frame() could consume it. So
that I could pick a bunch of patches from my RFC back to switch cpumap
to GRO finally :D

> 
> --Jesper
> 

Thanks,
Olek