From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755471Ab1G0Vs2 (ORCPT ); Wed, 27 Jul 2011 17:48:28 -0400 Received: from mga09.intel.com ([134.134.136.24]:28839 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755454Ab1G0VsY (ORCPT ); Wed, 27 Jul 2011 17:48:24 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.67,279,1309762800"; d="scan'208";a="32826295" From: Andi Kleen References: <20110727247.325703029@firstfloor.org> In-Reply-To: <20110727247.325703029@firstfloor.org> To: kronos.it@gmail.com, jrickman@myamigos.us, w5pny@arrl.net, dz@debian.org, khali@linux-fr.org, gregkh@suse.de, ak@linux.intel.com, linux-kernel@vger.kernel.org, stable@kernel.org, tim.bird@am.sony.com Subject: [PATCH] [25/99] i8k: Avoid lahf in 64-bit code Message-Id: <20110727214823.BF1732403FF@tassilo.jf.intel.com> Date: Wed, 27 Jul 2011 14:48:23 -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: Luca Tettamanti commit bc1f419c76a2d6450413ce4349f4e4a07be011d5 upstream. i8k uses lahf to read the flag register in 64-bit code; early x86-64 CPUs, however, lack this instruction and we get an invalid opcode exception at runtime. Use pushf to load the flag register into the stack instead. Signed-off-by: Luca Tettamanti Reported-by: Jeff Rickman Tested-by: Jeff Rickman Tested-by: Harry G McGavran Jr Cc: Massimo Dal Zotto Signed-off-by: Jean Delvare Signed-off-by: Greg Kroah-Hartman Signed-off-by: Andi Kleen --- drivers/char/i8k.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) 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 @@ -138,8 +138,8 @@ static int i8k_smm(struct smm_regs *regs "movl %%edi,20(%%rax)\n\t" "popq %%rdx\n\t" "movl %%edx,0(%%rax)\n\t" - "lahf\n\t" - "shrl $8,%%eax\n\t" + "pushfq\n\t" + "popq %%rax\n\t" "andl $1,%%eax\n" :"=a"(rc) : "a"(regs)