From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755767Ab2GaEzt (ORCPT ); Tue, 31 Jul 2012 00:55:49 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:48821 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755673Ab2GaEu7 (ORCPT ); Tue, 31 Jul 2012 00:50:59 -0400 Message-Id: <20120731044317.351797099@decadent.org.uk> User-Agent: quilt/0.60-1 Date: Tue, 31 Jul 2012 05:43:48 +0100 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Tiejun Chen , Benjamin Herrenschmidt Subject: [ 38/73] powerpc: Add "memory" attribute for mfmsr() In-Reply-To: <20120731044310.013763753@decadent.org.uk> X-SA-Exim-Connect-IP: 2001:470:1f08:1539:21c:bfff:fe03:f805 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.2-stable review patch. If anyone has any objections, please let me know. ------------------ From: Tiejun Chen commit b416c9a10baae6a177b4f9ee858b8d309542fbef upstream. Add "memory" attribute in inline assembly language as a compiler barrier to make sure 4.6.x GCC don't reorder mfmsr(). Signed-off-by: Tiejun Chen Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Ben Hutchings --- arch/powerpc/include/asm/reg.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/include/asm/reg.h b/arch/powerpc/include/asm/reg.h index 2baeb7c..6386086 100644 --- a/arch/powerpc/include/asm/reg.h +++ b/arch/powerpc/include/asm/reg.h @@ -1025,7 +1025,8 @@ /* Macros for setting and retrieving special purpose registers */ #ifndef __ASSEMBLY__ #define mfmsr() ({unsigned long rval; \ - asm volatile("mfmsr %0" : "=r" (rval)); rval;}) + asm volatile("mfmsr %0" : "=r" (rval) : \ + : "memory"); rval;}) #ifdef CONFIG_PPC_BOOK3S_64 #define __mtmsrd(v, l) asm volatile("mtmsrd %0," __stringify(l) \ : : "r" (v) : "memory")