From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail202.messagelabs.com (mail202.messagelabs.com [216.82.254.227]) by kanga.kvack.org (Postfix) with SMTP id B62E76B005C for ; Fri, 30 Jan 2009 08:00:30 -0500 (EST) Subject: Re: marching through all physical memory in software From: Nigel Cunningham Reply-To: ncunningham-lkml@crca.org.au In-Reply-To: <20090130091304.GA9495@atrey.karlin.mff.cuni.cz> References: <497DD8E5.1040305@nortel.com> <20090126075957.69b64a2e@infradead.org> <497F5289.404@nortel.com> <20090128193813.GD1222@ucw.cz> <1233306324.11332.11.camel@nigel-laptop> <20090130091304.GA9495@atrey.karlin.mff.cuni.cz> Content-Type: text/plain Date: Sat, 31 Jan 2009 00:00:51 +1100 Message-Id: <1233320451.11332.13.camel@nigel-laptop> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org To: Pavel Machek Cc: "Eric W. Biederman" , Chris Friesen , Arjan van de Ven , linux-kernel@vger.kernel.org, Doug Thompson , linux-mm@kvack.org, bluesmoke-devel@lists.sourceforge.net List-ID: Hi again. On Fri, 2009-01-30 at 10:13 +0100, Pavel Machek wrote: > > Hi. > > > > On Wed, 2009-01-28 at 20:38 +0100, Pavel Machek wrote: > > > You can do the scrubbing today by echo reboot > /sys/power/disk; echo > > > disk > /sys/power/state :-)... or using uswsusp APIs. > > > > That won't work. The RAM retains its contents across a reboot, and even > > for a little while after powering off. > > Yes, and the original goal was to rewrite all the memory with same > contents so that parity errors don't accumulate. SO scrubbing here != > trying to clear it. Sorry - I think I missed something. AFAICS, hibernating is going to be a noop as far as doing anything to memory that's not touched by the process of hibernating goes. It won't clear it or scrub it or anything else. Regards, Nigel -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org