Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1765406AbZDHNKx (ORCPT ); Wed, 8 Apr 2009 09:10:53 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1765436AbZDHNGR (ORCPT ); Wed, 8 Apr 2009 09:06:17 -0400 Received: from mx3.mail.elte.hu ([157.181.1.138]:34964 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1765315AbZDHNGO (ORCPT ); Wed, 8 Apr 2009 09:06:14 -0400 Date: Wed, 8 Apr 2009 15:05:10 +0200 From: Ingo Molnar To: "Rafael J. Wysocki" Cc: Andrew Morton , Akinobu Mita , Alexander Beregalov , "linux-next@vger.kernel.org" , LKML , linux-arch@vger.kernel.org, "David S. Miller" , Benjamin Herrenschmidt , Paul Mackerras , Martin Schwidefsky , Heiko Carstens , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" Subject: Re: [PATCH] build fix for generic debug pagealloc Message-ID: <20090408130510.GM18581@elte.hu> References: <20090402094522.b29004c8.akpm@linux-foundation.org> <20090403164450.GC3047@elte.hu> <200904032238.55438.rjw@sisk.pl> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <200904032238.55438.rjw@sisk.pl> User-Agent: Mutt/1.5.18 (2008-05-17) X-ELTE-VirusStatus: clean X-ELTE-SpamScore: -1.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.5 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.2.5 -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1419 Lines: 41 * Rafael J. Wysocki wrote: > On Friday 03 April 2009, Ingo Molnar wrote: > > > > * Andrew Morton wrote: > > > > > > +config DEBUG_PAGEALLOC > > > > + bool "Debug page memory allocations" > > > > + depends on DEBUG_KERNEL && ARCH_SUPPORTS_DEBUG_PAGEALLOC > > > > + depends on !HIBERNATION || !PPC && !SPARC > > > > + ---help--- > > > > + Unmap pages from the kernel linear mapping after free_pages(). > > > > + This results in a large slowdown, but helps to find certain types > > > > + of memory corruptions. > > > > + > > > > > > I guess this is why it wasn't discovered in my compile testing. > > > It's quite regrettable that `make allmodconfig' didn't enable the > > > feature. That's what allmodconfig is for. > > > > Hm, i _do_ remember some hibernation magic fix from Rafael, in the > > area of debugalloc. Many months ago. > > > > Rafael, is it supposed to work? If yes, i think we should unblock > > it. > > Yes, it is, at least on x86. > > ISTR using DEBUG_PAGEALLOC with hibernation quite some time ago > already. Could you please send a patch to Andrew then to remove the above dependency? Ingo -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/