Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754974AbZI3WmK (ORCPT ); Wed, 30 Sep 2009 18:42:10 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754530AbZI3WmI (ORCPT ); Wed, 30 Sep 2009 18:42:08 -0400 Received: from smtp1.linux-foundation.org ([140.211.169.13]:37946 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754258AbZI3WmH (ORCPT ); Wed, 30 Sep 2009 18:42:07 -0400 Date: Wed, 30 Sep 2009 15:40:44 -0700 From: Andrew Morton To: Samuel Thibault Cc: linux-kernel@vger.kernel.org, Ingo Molnar , Thomas Gleixner , "H. Peter Anvin" , "David S. Miller" , Andi Kleen Subject: Re: [PATCH,TRIVIAL] Fix csum_ipv6_magic asm memory clobber Message-Id: <20090930154044.0c7ace16.akpm@linux-foundation.org> In-Reply-To: <20090926192748.GX7681@const.famille.thibault.fr> References: <20090926192748.GX7681@const.famille.thibault.fr> X-Mailer: Sylpheed version 2.2.4 (GTK+ 2.8.20; i486-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1353 Lines: 36 On Sat, 26 Sep 2009 21:27:48 +0200 Samuel Thibault wrote: > Just like ip_fast_csum, the assembly snippet in csum_ipv6_magic needs a > memory clobber, as it is only passed the address of the buffer, not a > memory reference to the buffer itself. > > Signed-Off-By: Samuel Thibault > Cc: stable@kernel.org > > diff --git a/arch/x86/include/asm/checksum_32.h b/arch/x86/include/asm/checksum_32.h > index 7c5ef8b..46fc474 100644 > --- a/arch/x86/include/asm/checksum_32.h > +++ b/arch/x86/include/asm/checksum_32.h > @@ -161,7 +161,8 @@ static inline __sum16 csum_ipv6_magic(const struct in6_addr *saddr, > "adcl $0, %0 ;\n" > : "=&r" (sum) > : "r" (saddr), "r" (daddr), > - "r" (htonl(len)), "r" (htonl(proto)), "0" (sum)); > + "r" (htonl(len)), "r" (htonl(proto)), "0" (sum) > + : "memory"); > > return csum_fold(sum); > } You describe it as "trivial" and also cc stable@kernel.org. These things are contradictory! Maybe backporting it is a good idea from a sleep-soundly-at-night POV. I don't know.. -- 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/