Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935526AbZDCUjG (ORCPT ); Fri, 3 Apr 2009 16:39:06 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1759201AbZDCUiw (ORCPT ); Fri, 3 Apr 2009 16:38:52 -0400 Received: from ogre.sisk.pl ([217.79.144.158]:35923 "EHLO ogre.sisk.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759249AbZDCUiv (ORCPT ); Fri, 3 Apr 2009 16:38:51 -0400 From: "Rafael J. Wysocki" To: Ingo Molnar Subject: Re: [PATCH] build fix for generic debug pagealloc Date: Fri, 3 Apr 2009 22:38:53 +0200 User-Agent: KMail/1.11.1 (Linux/2.6.29-rjw; KDE/4.2.1; x86_64; ; ) 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" References: <20090402094522.b29004c8.akpm@linux-foundation.org> <20090403164450.GC3047@elte.hu> In-Reply-To: <20090403164450.GC3047@elte.hu> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200904032238.55438.rjw@sisk.pl> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1249 Lines: 35 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. Thanks, Rafael -- 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/