From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755228Ab0IOTIy (ORCPT ); Wed, 15 Sep 2010 15:08:54 -0400 Received: from terminus.zytor.com ([198.137.202.10]:43298 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755126Ab0IOTIx (ORCPT ); Wed, 15 Sep 2010 15:08:53 -0400 Message-ID: <4C9119B1.7020808@zytor.com> Date: Wed, 15 Sep 2010 12:08:33 -0700 From: "H. Peter Anvin" User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.8) Gecko/20100806 Fedora/3.1.2-1.fc13 Thunderbird/3.1.2 MIME-Version: 1.0 To: ling.ma@intel.com CC: mingo@elte.hu, tglx@linutronix.de, linux-kernel@vger.kernel.org Subject: Re: [PATCH V3] [X86] Fix potential issue on memmove References: <1284515426-7417-1-git-send-email-ling.ma@intel.com> In-Reply-To: <1284515426-7417-1-git-send-email-ling.ma@intel.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 09/14/2010 06:50 PM, ling.ma@intel.com wrote: > From: Ma Ling > > memmove allow source and destination address to be overlap, > but no limitation for memcpy. So memmove use forward or > backward copy mode to handle src > dest and dest > src cases respectively. > However memcpy has not address overlap, it may use any copy mode > theoretically. Our original memmove will call memcpy and assume > it must use forward copy mode, otherwise the system will crash, > it is potential issue. The patch based on tip/x86/mem avoids > this assumption. > > Signed-off-by: Ma Ling This patch is certainly not based on the current tip:x86/mem. Could you check out the current tip:x86/mem (which has a previous patch of yours in it) and submit an incremental patch with a description about what updates the previous patch and why? -hpa