From patchwork Sun Aug 19 02:56:26 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andi Kleen X-Patchwork-Id: 1343731 Return-Path: X-Original-To: patchwork-linux-kbuild@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork2.kernel.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by patchwork2.kernel.org (Postfix) with ESMTP id 96838DFFCC for ; Sun, 19 Aug 2012 03:14:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754645Ab2HSC6u (ORCPT ); Sat, 18 Aug 2012 22:58:50 -0400 Received: from mga11.intel.com ([192.55.52.93]:44069 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753454Ab2HSC5h (ORCPT ); Sat, 18 Aug 2012 22:57:37 -0400 Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by fmsmga102.fm.intel.com with ESMTP; 18 Aug 2012 19:57:25 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.77,792,1336374000"; d="scan'208";a="210415449" Received: from tassilo.jf.intel.com ([10.7.201.151]) by fmsmga002.fm.intel.com with ESMTP; 18 Aug 2012 19:57:25 -0700 Received: by tassilo.jf.intel.com (Postfix, from userid 501) id 6DD502419BE; Sat, 18 Aug 2012 19:57:25 -0700 (PDT) From: Andi Kleen To: linux-kernel@vger.kernel.org Cc: x86@kernel.org, mmarek@suse.cz, linux-kbuild@vger.kernel.org, JBeulich@suse.com, akpm@linux-foundation.org, Andi Kleen Subject: [PATCH 30/74] x86, lto: Fix AMD K6 indirect call check Date: Sat, 18 Aug 2012 19:56:26 -0700 Message-Id: <1345345030-22211-31-git-send-email-andi@firstfloor.org> X-Mailer: git-send-email 1.7.7.6 In-Reply-To: <1345345030-22211-1-git-send-email-andi@firstfloor.org> References: <1345345030-22211-1-git-send-email-andi@firstfloor.org> Sender: linux-kbuild-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org From: Andi Kleen The AMD K6 errata check relies on timing a indirect call. But the way it was written it could be optimized to a direct call. Force gcc to actually do a indirect call and not just constant resolve the target address. Signed-off-by: Andi Kleen --- arch/x86/kernel/cpu/amd.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c index 2c02d92..cb72014 100644 --- a/arch/x86/kernel/cpu/amd.c +++ b/arch/x86/kernel/cpu/amd.c @@ -116,7 +116,7 @@ static void __cpuinit init_amd_k6(struct cpuinfo_x86 *c) */ n = K6_BUG_LOOP; - f_vide = vide; + asm("" : "=r" (f_vide) : "0" (vide)); rdtscl(d); while (n--) f_vide();