netdev - Re: [RFC] implicit per-namespace devlink instance to set kernel resource limitations

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 for Android: free password hash cracker in your pocket

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

Date:   Wed, 7 Aug 2019 14:55:14 -0600
From:   David Ahern <dsahern@...il.com>
To:     Jakub Kicinski <jakub.kicinski@...ronome.com>
Cc:     Andrew Lunn <andrew@...n.ch>, Jiri Pirko <jiri@...nulli.us>,
        netdev@...r.kernel.org, davem@...emloft.net, mlxsw@...lanox.com,
        f.fainelli@...il.com, vivien.didelot@...il.com, mkubecek@...e.cz,
        stephen@...workplumber.org, daniel@...earbox.net,
        brouer@...hat.com, eric.dumazet@...il.com
Subject: Re: [RFC] implicit per-namespace devlink instance to set kernel
 resource limitations

On 8/7/19 12:49 PM, Jakub Kicinski wrote:
> Perhaps I'm misinterpreting your point there.

yes, this thread is getting out of hand.

I am not pushing for an in-kernel, fib resource controller. Jiri wants
to remove the existing devlink resource code from netdevsim into a
standalone driver, code that was added for testing and as the commit log
shows as a demonstration of how one could create a controller using the
devlink API. I added some color commentary as to why a devlink
controller makes sense for the use case and how it should work, but I am
not asking for such a controller to be added to the kernel.

The netdevsim resource controller is counter based; the absolute
simplest form of limits. If I wanted basic counting for a fib resource
controller, I would add an option to limit the number of fib rules and
routes using sysctl similar to what exists for neighbors. Consistency. I
don't need the overhead and unrelated messiness of cgroups. I don't need
the overhead of handling fib notifiers. fib (rule) add -- check counter,
increment counter; fib (rule) delete -- decrement counter. Simple, per
namespace, done.