linux-kernel - Re: [RFC -v2 PATCH 2/3] sched: add yield

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: <1292699629.1181.58.camel@marge.simson.net>
Date:	Sat, 18 Dec 2010 20:13:49 +0100
From:	Mike Galbraith <mgalbraith@...e.de>
To:	Avi Kivity <avi@...hat.com>
Cc:	Rik van Riel <riel@...hat.com>, kvm@...r.kernel.org,
	linux-kernel@...r.kernel.org,
	Srivatsa Vaddagiri <vatsa@...ux.vnet.ibm.com>,
	Peter Zijlstra <a.p.zijlstra@...llo.nl>,
	Chris Wright <chrisw@...s-sol.org>
Subject: Re: [RFC -v2 PATCH 2/3] sched: add yield_to function

On Sat, 2010-12-18 at 19:08 +0200, Avi Kivity wrote:
> On 12/17/2010 09:15 AM, Mike Galbraith wrote:
> > BTW, with this vruntime donation thingy, what prevents a task from
> > forking off accomplices who do nothing but wait for a wakeup and
> > yield_to(exploit)?
> >
> 
> What's the difference between that and forking off accomplices who 
> run(exploit) directly?

The clock still advances.  What I described is a clock stopper.

> Many threads dominating the scheduler has been solved by group 
> scheduling.  We need to make sure directed yield doesn't violate that, 
> but I don't see new problems.

Let it become possible to stop clocks, and you surely will :)

	-Mike


--
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/