From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wg0-f51.google.com (mail-wg0-f51.google.com [74.125.82.51]) by kanga.kvack.org (Postfix) with ESMTP id 973B26B0035 for ; Wed, 2 Jul 2014 22:23:36 -0400 (EDT) Received: by mail-wg0-f51.google.com with SMTP id x12so11881334wgg.22 for ; Wed, 02 Jul 2014 19:23:36 -0700 (PDT) Received: from e28smtp04.in.ibm.com (e28smtp04.in.ibm.com. [122.248.162.4]) by mx.google.com with ESMTPS id y20si17418700wie.93.2014.07.02.19.23.34 for (version=TLSv1 cipher=RC4-SHA bits=128/128); Wed, 02 Jul 2014 19:23:35 -0700 (PDT) Received: from /spool/local by e28smtp04.in.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Thu, 3 Jul 2014 07:53:31 +0530 Received: from d28relay03.in.ibm.com (d28relay03.in.ibm.com [9.184.220.60]) by d28dlp02.in.ibm.com (Postfix) with ESMTP id 34EED394003E for ; Thu, 3 Jul 2014 07:53:29 +0530 (IST) Received: from d28av05.in.ibm.com (d28av05.in.ibm.com [9.184.220.67]) by d28relay03.in.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id s632Opp111010550 for ; Thu, 3 Jul 2014 07:54:51 +0530 Received: from d28av05.in.ibm.com (localhost [127.0.0.1]) by d28av05.in.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id s632NSff001279 for ; Thu, 3 Jul 2014 07:53:28 +0530 Date: Thu, 3 Jul 2014 10:23:26 +0800 From: Wei Yang Subject: Re: mm: slub: invalid memory access in setup_object Message-ID: <20140703022326.GA5174@richard> Reply-To: Wei Yang References: <53AAFDF7.2010607@oracle.com> <20140701144947.5ce3f93729759d8f38d7813a@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20140701144947.5ce3f93729759d8f38d7813a@linux-foundation.org> Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: Christoph Lameter , David Rientjes , Sasha Levin , Wei Yang , Pekka Enberg , Matt Mackall , "linux-mm@kvack.org" , LKML , Dave Jones On Tue, Jul 01, 2014 at 02:49:47PM -0700, Andrew Morton wrote: >On Tue, 1 Jul 2014 09:58:52 -0500 (CDT) Christoph Lameter wrote: > >> On Mon, 30 Jun 2014, David Rientjes wrote: >> >> > It's not at all clear to me that that patch is correct. Wei? >> >> Looks ok to me. But I do not like the convoluted code in new_slab() which >> Wei's patch does not make easier to read. Makes it difficult for the >> reader to see whats going on. >> >> Lets drop the use of the variable named "last". >> >> >> Subject: slub: Only call setup_object once for each object >> >> Modify the logic for object initialization to be less convoluted >> and initialize an object only once. >> > >Well, um. Wei's changelog was much better: > >: When a kmem_cache is created with ctor, each object in the kmem_cache will >: be initialized before use. In the slub implementation, the first object >: will be initialized twice. >: >: This patch avoids the duplication of initialization of the first object. >: >: Fixes commit 7656c72b5a63: ("SLUB: add macros for scanning objects in a >: slab"). > >I can copy that text over and add the reported-by etc (ho hum) but I >have a tiny feeling that this patch hasn't been rigorously tested? >Perhaps someone (Wei?) can do that? The result of the simple test is the same. And my laptop works a whole day with this patch. Thanks > >And we still don't know why Sasha's kernel went oops. -- Richard Yang Help you, Help me -- 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