From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932617Ab2AEP2u (ORCPT ); Thu, 5 Jan 2012 10:28:50 -0500 Received: from terminus.zytor.com ([198.137.202.10]:45962 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755559Ab2AEP2t (ORCPT ); Thu, 5 Jan 2012 10:28:49 -0500 References: <4F05BBFE020000780006A983@nat28.tlf.novell.com> User-Agent: K-9 Mail for Android In-Reply-To: <4F05BBFE020000780006A983@nat28.tlf.novell.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Subject: Re: x86-64: memset()/memcpy() not fully standards compliant From: "hpanvin@gmail.com" Date: Thu, 05 Jan 2012 07:27:34 -0800 To: Jan Beulich , mingo@elte.hu, tglx@linutronix.de CC: Andi Kleen , linux-kernel@vger.kernel.org Message-ID: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Yes, I think it is probably Just A Bug. Unless it can be shown it makes it much slower, let's fix. Jan Beulich wrote: >Forever these two functions have been limited to deal with at most 4G >at a time. While I cannot point out an in-tree user that would require >larger sizes, it is now the second time that within our Xen kernel we >got >bitten by that limitation. Would you nevertheless accept a patch to >eliminate those shortcomings (iirc there may need to be workarounds >for CPU bugs when it comes to using string instructions on such large >blocks, albeit memmove() doesn't seem to care)? > >Otherwise, is there any rationale for this sort of lurking bug? > >Thanks, Jan -- Sent from my Android phone with K-9 Mail. Please excuse my brevity.