Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754051Ab1CZT5n (ORCPT ); Sat, 26 Mar 2011 15:57:43 -0400 Received: from mx3.mail.elte.hu ([157.181.1.138]:48417 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753745Ab1CZT5m (ORCPT ); Sat, 26 Mar 2011 15:57:42 -0400 Date: Sat, 26 Mar 2011 20:57:22 +0100 From: Ingo Molnar To: Christoph Lameter Cc: Eric Dumazet , Pekka Enberg , Thomas Gleixner , torvalds@linux-foundation.org, akpm@linux-foundation.org, tj@kernel.org, npiggin@kernel.dk, rientjes@google.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH] slub: Disable the lockless allocator Message-ID: <20110326195722.GA7748@elte.hu> References: <20110324185258.GA28370@elte.hu> <20110324192247.GA5477@elte.hu> <20110326112725.GA28612@elte.hu> <20110326114736.GA8251@elte.hu> <1301161507.2979.105.camel@edumazet-laptop> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.20 (2009-08-17) X-ELTE-SpamScore: -2.0 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-2.0 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.3.1 -2.0 BAYES_00 BODY: Bayes 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: 1160 Lines: 38 * Christoph Lameter wrote: > On Sat, 26 Mar 2011, Christoph Lameter wrote: > > > Tejun: Whats going on there? I should be getting offsets into the per cpu > > area and not kernel addresses. > > Its a UP kernel running on dual Athlon. So its okay ... Argh.... The > following patch fixes it by using the fallback code for cmpxchg_double: > > > > Subject: per_cpu: Fixup cmpxchg_double for !SMP > > cmpxchg_double should only be provided for SMP. In the UP case > the GS register is not defined and the function will fail. > > Signed-off-by: Christoph Lameter I.e. the bug got introduced by: | commit b9ec40af0e18fb7d02106be148036c2ea490fdf9 | Author: Christoph Lameter | Date: Mon Feb 28 11:02:24 2011 +0100 | | percpu, x86: Add arch-specific this_cpu_cmpxchg_double() support and then the lockless allocator made use of it, right? Thanks, 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/