From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756850AbYKKOPu (ORCPT ); Tue, 11 Nov 2008 09:15:50 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755858AbYKKOPk (ORCPT ); Tue, 11 Nov 2008 09:15:40 -0500 Received: from ogre.sisk.pl ([217.79.144.158]:53523 "EHLO ogre.sisk.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755691AbYKKOPk (ORCPT ); Tue, 11 Nov 2008 09:15:40 -0500 From: "Rafael J. Wysocki" To: Pavel Machek Subject: Re: CONFIG_NUMA breaks hibernation on x86-32 with PAE Date: Tue, 11 Nov 2008 15:20:21 +0100 User-Agent: KMail/1.9.9 Cc: Andi Kleen , Ingo Molnar , kernel list , "H. Peter Anvin" References: <20081109140726.GB1786@ucw.cz> <200811101928.04565.rjw@sisk.pl> <20081111104551.GE5464@elf.ucw.cz> In-Reply-To: <20081111104551.GE5464@elf.ucw.cz> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200811111520.22386.rjw@sisk.pl> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tuesday, 11 of November 2008, Pavel Machek wrote: > On Mon 2008-11-10 19:28:03, Rafael J. Wysocki wrote: > > On Monday, 10 of November 2008, Andi Kleen wrote: > > > Ingo Molnar writes: > > > > > > > > No good ideas - the bug description gives me the impression of memory > > > > maps save/restore hickup in the hibernation code - and memory maps are > > > > pretty much the only thing that are significantly different on NUMA. > > > > > > I assume the problem happened on a single node system. > > > On single node the memory map should be actually quite similar > > > to the UMA case. > > > > It is. However, the problem is 100% reproducible on any 32-bit single-node > > system with CONFIG_NUMA set, from what I can tell. > > > > It doesn't happen if the kernel is booted with highmem=0, so it looks like > > the code that saves highmem causes the problem to happen. However, this > > same code works well for all of the !CONFIG_NUMA cases and practically only > > the only non-open-coded it uses is kmap_atomic(). > > > > > One possibility would be to bisect if it ever worked? > > > > Not sure it did, probably not. :-( > > Well, interesting point would be just before this commit: > > > commit 8357376d3df21b7d6f857931a57ac50da9c66e26 > tree daf2c369e9b79d24c1666323b3ae75189e482a4a > parent bf73bae6ba0dc4bd4f1e570feb34a06b72725af6 > author Rafael J. Wysocki Wed, 06 Dec 2006 20:34:18 -0800 > committer Linus Torvalds Thu, 07 Dec 2006 > 08:39:27 -0800 > > [PATCH] swsusp: Improve handling of highmem > > Currently swsusp saves the contents of highmem pages by copying > them to the > normal zone which is quite inefficient (eg. it requires two > normal pages > to be used for saving one highmem page). This may be improved by > using > highmem for saving the contents of saveable highmem pages. > > ...highmem handling was way simpler in those good old days ;-) Please stop kidding, this is a serious issue. The hibernation code _works_ with all kinds of highmem when CONFIG_NUMA is unset. Thanks, Rafael