From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753571Ab1G0AfG (ORCPT ); Tue, 26 Jul 2011 20:35:06 -0400 Received: from mga01.intel.com ([192.55.52.88]:6474 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753482Ab1G0Ae7 (ORCPT ); Tue, 26 Jul 2011 20:34:59 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.67,272,1309762800"; d="scan'208";a="32659161" From: Andi Kleen References: <20110726534.972201586@firstfloor.org> In-Reply-To: <20110726534.972201586@firstfloor.org> To: jim876@xs4all.nl, andi@firstfloor.org, schwab@linux-m68k.org, torvalds@linux-foundation.org, ak@linux.intel.com, linux-kernel@vger.kernel.org, stable@kernel.org, tim.bird@am.sony.com, linux-kernel@vger.kernel.org, stable@vger.kernel.org Subject: [PATCH] [7/98] i8k: Tell gcc that *regs gets clobbered Message-Id: <20110727003459.1BD952403FF@tassilo.jf.intel.com> Date: Tue, 26 Jul 2011 17:34:59 -0700 (PDT) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.35-longterm review patch. If anyone has any objections, please let me know. ------------------ From: Jim Bos [ upstream commit 6b4e81db2552bad04100e7d5ddeed7e848f53b48 ] More recent GCC caused the i8k driver to stop working, on Slackware compiler was upgraded from gcc-4.4.4 to gcc-4.5.1 after which it didn't work anymore, meaning the driver didn't load or gave total nonsensical output. As it turned out the asm(..) statement forgot to mention it modifies the *regs variable. Credits to Andi Kleen and Andreas Schwab for providing the fix. Signed-off-by: Jim Bos Cc: Andi Kleen Cc: Andreas Schwab Signed-off-by: Linus Torvalds Signed-off-by: Andi Kleen Index: linux-2.6.35.y/drivers/char/i8k.c =================================================================== --- linux-2.6.35.y.orig/drivers/char/i8k.c +++ linux-2.6.35.y/drivers/char/i8k.c @@ -141,7 +141,7 @@ static int i8k_smm(struct smm_regs *regs "lahf\n\t" "shrl $8,%%eax\n\t" "andl $1,%%eax\n" - :"=a"(rc) + :"=a"(rc), "+m" (*regs) : "a"(regs) : "%ebx", "%ecx", "%edx", "%esi", "%edi", "memory"); #else @@ -166,7 +166,8 @@ static int i8k_smm(struct smm_regs *regs "movl %%edx,0(%%eax)\n\t" "lahf\n\t" "shrl $8,%%eax\n\t" - "andl $1,%%eax\n":"=a"(rc) + "andl $1,%%eax\n" + :"=a"(rc), "+m" (*regs) : "a"(regs) : "%ebx", "%ecx", "%edx", "%esi", "%edi", "memory"); #endif