linux-kernel - Re: [patch 0/2] cpusets, cpu_cgroup: disallow attaching kthreadd

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]

Message-ID: <1334403322.2528.73.camel@twins>
Date:	Sat, 14 Apr 2012 13:35:22 +0200
From:	Peter Zijlstra <a.p.zijlstra@...llo.nl>
To:	David Rientjes <rientjes@...gle.com>
Cc:	Hiroyuki Kamezawa <kamezawa.hiroyuki@...il.com>,
	Tejun Heo <tj@...nel.org>, Mike Galbraith <mgalbraith@...e.de>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Ingo Molnar <mingo@...hat.com>,
	Paul Menage <paul@...lmenage.org>,
	LKML <linux-kernel@...r.kernel.org>,
	Li Zefan <lizefan@...wei.com>
Subject: Re: [patch 0/2] cpusets, cpu_cgroup: disallow attaching kthreadd

On Mon, 2012-04-09 at 17:52 -0700, David Rientjes wrote:
> On Sun, 8 Apr 2012, Hiroyuki Kamezawa wrote:
> 
> > I'm sorry if I didn't read e-mails while a trip....let me understand...
> > 
> >  - Tejun at el, tries to disallow to move kthreadd into cgroups other than root.
> >  - You wants to account kthreadd's activity under memg at el.
> > 
> 
> memcg isn't the only use case, you can also use it for cpuacct and any 
> other future cgroup that wants to do so.

fwiw, it would be ever so nice to get rid of cpuacct -- its a horrendous
piece of crap.

Anyway, memcg is more than an bean counter, it can do actual
enforcement, so by allowing it outside the root group you allow it into
an enforced group, making it so that you cannot spawn more threads at
some point, which might mean making your kernel not work properly.

Just fix memcg already to account whatever you want for the root group.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/