netdev - Re: [net-next,RFC PATCH] net: Extend TC limit beyond 16 to 255

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, 23 Apr 2021 14:19:37 -0700
From:   Stephen Hemminger <stephen@...workplumber.org>
To:     Amritha Nambiar <amritha.nambiar@...el.com>
Cc:     netdev@...r.kernel.org, davem@...emloft.net, kuba@...nel.org,
        jhs@...atatu.com, jiri@...nulli.us, xiyou.wangcong@...il.com,
        john.fastabend@...il.com, alexander.duyck@...il.com,
        vinicius.gomes@...el.com, vedang.patel@...el.com,
        sridhar.samudrala@...el.com
Subject: Re: [net-next,RFC PATCH] net: Extend TC limit beyond 16 to 255

On Fri, 23 Apr 2021 14:12:20 -0700
Amritha Nambiar <amritha.nambiar@...el.com> wrote:

> Extend the max limit of TCs to 255 (max value of 8-bit num_tc)
> from current max of 16. This would allow creating more than 16
> queue-sets and offloading them on devices with large number of
> queues using the mqprio scheduler.
> Also, changed the static allocation of struct
> tc_mqprio_qopt_offload mqprio to dynamic allocation on heap to
> fit within frame size as the size of attributes increases
> proportionally with the max number of TCs.
> 
> Signed-off-by: Amritha Nambiar <amritha.nambiar@...el.com>

This breaks the userspace API, similar things have been proposed
before and rejected.