linux-kernel - Re: [PATCH net-next v11 00/10] tun: Introduce virtio-net hashing feature

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]

Message-ID: <CAPpAL=yfgiuFA-SyrCe0Ud8Wm9tJMcMm9L4Q-AnnuRzN+Q9M=A@mail.gmail.com>
Date: Tue, 18 Mar 2025 10:09:50 +0800
From: Lei Yang <leiyang@...hat.com>
To: Akihiko Odaki <akihiko.odaki@...nix.com>
Cc: Jonathan Corbet <corbet@....net>, Willem de Bruijn <willemdebruijn.kernel@...il.com>, 
	"David S. Miller" <davem@...emloft.net>, Eric Dumazet <edumazet@...gle.com>, 
	Jakub Kicinski <kuba@...nel.org>, Paolo Abeni <pabeni@...hat.com>, 
	"Michael S. Tsirkin" <mst@...hat.com>, Xuan Zhuo <xuanzhuo@...ux.alibaba.com>, 
	Shuah Khan <shuah@...nel.org>, linux-doc@...r.kernel.org, linux-kernel@...r.kernel.org, 
	netdev@...r.kernel.org, kvm@...r.kernel.org, 
	virtualization@...ts.linux-foundation.org, linux-kselftest@...r.kernel.org, 
	Yuri Benditovich <yuri.benditovich@...nix.com>, Andrew Melnychenko <andrew@...nix.com>, 
	Stephen Hemminger <stephen@...workplumber.org>, gur.stavi@...wei.com, 
	Simon Horman <horms@...nel.org>, Jason Wang <jasowang@...hat.com>
Subject: Re: [PATCH net-next v11 00/10] tun: Introduce virtio-net hashing feature

QE tested this series of patches v11 under linux-next repo with
virtio-net regression tests, everything works fine.

Tested-by: Lei Yang <leiyang@...hat.com>

On Tue, Mar 18, 2025 at 8:29 AM Jason Wang <jasowang@...hat.com> wrote:
>
> On Mon, Mar 17, 2025 at 6:58 PM Akihiko Odaki <akihiko.odaki@...nix.com> wrote:
> >
> > virtio-net have two usage of hashes: one is RSS and another is hash
> > reporting. Conventionally the hash calculation was done by the VMM.
> > However, computing the hash after the queue was chosen defeats the
> > purpose of RSS.
> >
> > Another approach is to use eBPF steering program. This approach has
> > another downside: it cannot report the calculated hash due to the
> > restrictive nature of eBPF.
> >
> > Introduce the code to compute hashes to the kernel in order to overcome
> > thse challenges.
> >
> > An alternative solution is to extend the eBPF steering program so that it
> > will be able to report to the userspace, but it is based on context
> > rewrites, which is in feature freeze. We can adopt kfuncs, but they will
> > not be UAPIs. We opt to ioctl to align with other relevant UAPIs (KVM
> > and vhost_net).
> >
> > The patches for QEMU to use this new feature was submitted as RFC and
> > is available at:
> > https://patchew.org/QEMU/20250313-hash-v4-0-c75c494b495e@daynix.com/
> >
> > This work was presented at LPC 2024:
> > https://lpc.events/event/18/contributions/1963/
> >
> > V1 -> V2:
> >   Changed to introduce a new BPF program type.
> >
> > Signed-off-by: Akihiko Odaki <akihiko.odaki@...nix.com>
> > ---
> > Changes in v11:
> > - Added the missing code to free vnet_hash in patch
> >   "tap: Introduce virtio-net hash feature".
> > - Link to v10: https://lore.kernel.org/r/20250313-rss-v10-0-3185d73a9af0@daynix.com
> >
>
> We only have 2 or 3 points that need to be sorted out. Let's hold on
> to the iteration until we had an agreement.
>
> Thanks
>