linux-kernel - Re: [ckrm-tech] RFC: Memory Controller

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]

Message-ID: <45485357.6050403@openvz.org>
Date:	Wed, 01 Nov 2006 10:57:11 +0300
From:	Pavel Emelianov <xemul@...nvz.org>
To:	Dave Hansen <haveblue@...ibm.com>
CC:	Pavel Emelianov <xemul@...nvz.org>, balbir@...ibm.com,
	vatsa@...ibm.com, dev@...nvz.org, sekharan@...ibm.com,
	ckrm-tech@...ts.sourceforge.net, linux-kernel@...r.kernel.org,
	pj@....com, matthltc@...ibm.com, dipankar@...ibm.com,
	rohitseth@...gle.com, menage@...gle.com
Subject: Re: [ckrm-tech] RFC: Memory Controller

Dave Hansen wrote:
> On Tue, 2006-10-31 at 11:48 +0300, Pavel Emelianov wrote:
>> If memory is considered to be unreclaimable then actions should be
>> taken at mmap() time, not later! Rejecting mmap() is the only way to
>> limit user in unreclaimable memory consumption.
> 
> I don't think this is necessarily true.  Today, if a kernel exceeds its
> allocation limits (runs out of memory) it gets killed.  Doing the
> limiting at mmap() time instead of fault time will keep a sparse memory
> applications from even being able to run.

If limiting _every_ mapping it will, but when limiting only
"private" mappings - no problems at all. BC code lives for
more than 3 years already and no claims from users on this
question yet.

> Now, failing an mmap() is a wee bit more graceful than a SIGBUS, but it
> certainly introduces its own set of problems.
> 
> -- Dave
> 
> 

-
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/