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Date: Tue, 8 Jun 2010 17:06:30 -0700
From: Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [patch -mm 01/18] oom: filter tasks not sharing the same cpuset
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To: David Rientjes <rientjes@google.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>, Rik van Riel <riel@redhat.com>, Nick Piggin <npiggin@suse.de>, Oleg Nesterov <oleg@redhat.com>, KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>, Balbir Singh <balbir@linux.vnet.ibm.com>, linux-mm@kvack.org
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On Tue, 8 Jun 2010 16:54:31 -0700 (PDT)
David Rientjes <rientjes@google.com> wrote:

> On Tue, 8 Jun 2010, Andrew Morton wrote:
> 
> > And I wonder if David has observed some problem which the 2010 change
> > fixes!
> > 
> 
> Yes, as explained in my changelog.  I'll paste it:
> 
> Tasks that do not share the same set of allowed nodes with the task that
> triggered the oom should not be considered as candidates for oom kill.
> 
> Tasks in other cpusets with a disjoint set of mems would be unfairly
> penalized otherwise because of oom conditions elsewhere; an extreme
> example could unfairly kill all other applications on the system if a
> single task in a user's cpuset sets itself to OOM_DISABLE and then uses
> more memory than allowed.

OK, so Nick's change didn't anticipate things being set to OOM_DISABLE?

OOM_DISABLE seems pretty dangerous really - allows malicious
unprivileged users to go homicidal?

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