linux-kernel - Re: [RFC PATCH net-next 0/2] net: Use SMP threads for backlog NAPI.

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

Message-ID: <20230814112421.5a2fa4f6@kernel.org>
Date:   Mon, 14 Aug 2023 11:24:21 -0700
From:   Jakub Kicinski <kuba@...nel.org>
To:     Sebastian Andrzej Siewior <bigeasy@...utronix.de>
Cc:     linux-kernel@...r.kernel.org, netdev@...r.kernel.org,
        "David S. Miller" <davem@...emloft.net>,
        Eric Dumazet <edumazet@...gle.com>,
        Paolo Abeni <pabeni@...hat.com>,
        Peter Zijlstra <peterz@...radead.org>,
        Thomas Gleixner <tglx@...utronix.de>,
        Wander Lairson Costa <wander@...hat.com>
Subject: Re: [RFC PATCH net-next 0/2] net: Use SMP threads for backlog NAPI.

On Mon, 14 Aug 2023 11:35:26 +0200 Sebastian Andrzej Siewior wrote:
> The RPS code and "deferred skb free" both send IPI/ function call
> to a remote CPU in which a softirq is raised. This leads to a warning on
> PREEMPT_RT because raising softiqrs from function call led to undesired
> behaviour in the past. I had duct tape in RT for the "deferred skb free"
> and Wander Lairson Costa reported the RPS case.

Could you find a less invasive solution?
backlog is used by veth == most containerized environments.
This change has a very high risk of regression for a lot of people.