From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-f45.google.com (mail-pa0-f45.google.com [209.85.220.45]) by kanga.kvack.org (Postfix) with ESMTP id 3D6606B0038 for ; Sun, 22 Mar 2015 19:54:06 -0400 (EDT) Received: by pacwe9 with SMTP id we9so172796302pac.1 for ; Sun, 22 Mar 2015 16:54:06 -0700 (PDT) Received: from shards.monkeyblade.net (shards.monkeyblade.net. [2001:4f8:3:36:211:85ff:fe63:a549]) by mx.google.com with ESMTP id pt7si19328964pdb.96.2015.03.22.16.54.05 for ; Sun, 22 Mar 2015 16:54:05 -0700 (PDT) Date: Sun, 22 Mar 2015 19:54:03 -0400 (EDT) Message-Id: <20150322.195403.1653355516554747742.davem@davemloft.net> Subject: Re: 4.0.0-rc4: panic in free_block From: David Miller In-Reply-To: <550F51D5.2010804@oracle.com> References: <20150322.182311.109269221031797359.davem@davemloft.net> <550F51D5.2010804@oracle.com> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: david.ahern@oracle.com Cc: torvalds@linux-foundation.org, sparclinux@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, bpicco@meloft.net From: David Ahern Date: Sun, 22 Mar 2015 17:35:49 -0600 > I don't know if you caught Bob's message; he has a hack to bypass > memcpy and memmove in mm/slab.c use a for loop to move entries. With > the hack he is not seeing the problem. > > This is the hack: > > +static void move_entries(void *dest, void *src, int nr) > +{ > + unsigned long *dp = dest; > + unsigned long *sp = src; > + > + for (; nr; nr--, dp++, sp++) > + *dp = *sp; > +} > + > > and then replace the mempy and memmove calls in transfer_objects, > cache_flusharray and drain_array to use move_entries. > > I just put it on 4.0.0-rc4 and ditto -- problem goes away, so it > clearly suggests the memcpy or memmove are the root cause. Thanks, didn't notice that. So, something is amuck. -- 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