linux-kernel - Re: [PATCH] copy over oom

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, 23 Jul 2009 16:29:01 -0700 (PDT)
From:	David Rientjes <rientjes@...gle.com>
To:	KOSAKI Motohiro <kosaki.motohiro@...fujitsu.com>
cc:	Paul Menage <menage@...gle.com>, Rik van Riel <riel@...hat.com>,
	linux-kernel@...r.kernel.org, akpm@...ux-foundation.org,
	mel@....ul.ie, npiggin@...e.de
Subject: Re: [PATCH] copy over oom_adj value at fork time

On Fri, 24 Jul 2009, KOSAKI Motohiro wrote:

> > It's the API that's existed for years with no complaints, AFAICS.
> 
> I think thead and vfork() should be separeted on this discussion.
> I agree vfork() regression should be fixed. but I don't think anyone
> hope per-thread oom score. 
> 
> Of cource, if simple reverting is best way, I don't oppose this.... ;-)
> 

Simply reverting it isn't an option unless you fix the underlying livelock 
problem that my patches originally addressed and no viable alternative has 
been proposed.

On the other hand, I think adding /proc/pid/oom_adj_child would solve the 
userspace issue.  oom_adj_child would be the oom_adj value that is used by 
the newly initialized mm_struct; this would allow the vfork'd child to 
share the same oom_score with the parent and then be replaced with an 
alternate score on execve().

oom_adj_child would only be allowed to be greater (i.e. the more preferred 
victim) than oom_adj for any given thread since the oom killer tries to 
kill a child of the selected task first if it doesn't share memory.
--
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/