linux-kernel - Re: [PATCH repost] sched: export sched

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]

Date:	Thu, 01 Jul 2010 13:43:23 +0200
From:	Peter Zijlstra <peterz@...radead.org>
To:	"Michael S. Tsirkin" <mst@...hat.com>
Cc:	Ingo Molnar <mingo@...e.hu>, Sridhar Samudrala <sri@...ibm.com>,
	Tejun Heo <tj@...nel.org>, Oleg Nesterov <oleg@...hat.com>,
	netdev <netdev@...r.kernel.org>,
	lkml <linux-kernel@...r.kernel.org>,
	"kvm@...r.kernel.org" <kvm@...r.kernel.org>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Dmitri Vorobiev <dmitri.vorobiev@...ial.com>,
	Jiri Kosina <jkosina@...e.cz>,
	Thomas Gleixner <tglx@...utronix.de>,
	Andi Kleen <ak@...ux.intel.com>
Subject: Re: [PATCH repost] sched: export sched_set/getaffinity to modules

On Thu, 2010-07-01 at 13:19 +0200, Peter Zijlstra wrote:
> On Thu, 2010-07-01 at 14:07 +0300, Michael S. Tsirkin wrote:
> > Author: Sridhar Samudrala <sri@...ibm.com>
> > 
> > sched: export sched_set/getaffinity to modules
> > 
> > vhost-net driver wants to copy the affinity from the
> > owner thread to thread it creates. Export
> > sched_set/get affinity to modules to make this possible
> > when vhost is built as a module.

> Urgh,.. so why again is that a good idea?

In particular:
 - who sets the affinity of the task? 
 - why can't it set the kernel thread's affinity too?
 - what happens if someone changes the tasks' affinity?

So no, I don't think this is a sensible thing to do at all.
--
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/