Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755447AbdGSTqq (ORCPT ); Wed, 19 Jul 2017 15:46:46 -0400 Received: from mail-oi0-f41.google.com ([209.85.218.41]:32946 "EHLO mail-oi0-f41.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753848AbdGSTqo (ORCPT ); Wed, 19 Jul 2017 15:46:44 -0400 MIME-Version: 1.0 In-Reply-To: <20170719125310.2487451-5-arnd@arndb.de> References: <20170719125310.2487451-1-arnd@arndb.de> <20170719125310.2487451-5-arnd@arndb.de> From: Linus Torvalds Date: Wed, 19 Jul 2017 12:46:43 -0700 X-Google-Sender-Auth: ITD9TrxR7vWHkCl11D6jXZHAGIs Message-ID: Subject: Re: [PATCH 4/8] x86: io: add "memory" clobber to insb/insw/insl/outsb/outsw/outsl To: Arnd Bergmann Cc: "the arch/x86 maintainers" , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , Linux Kernel Mailing List , Borislav Petkov , Tom Lendacky Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 522 Lines: 12 On Wed, Jul 19, 2017 at 5:53 AM, Arnd Bergmann wrote: > > I tried to mark the exact input buffer as an output here, but couldn't > figure it out. As suggested by Linus, marking all memory as clobbered > however is good enough too. For the outs operations, I also add the > memory clobber, to force the input to be written to local variables. > This is probably already guaranteed by the "asm volatile", but it can't > hurt to do this for symmetry. Ack, obviously looks fine to me. Linus