From mboxrd@z Thu Jan 1 00:00:00 1970 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754937AbeAMSuy (ORCPT + 1 other); Sat, 13 Jan 2018 13:50:54 -0500 Received: from mail-wm0-f68.google.com ([74.125.82.68]:46575 "EHLO mail-wm0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753953AbeAMSuw (ORCPT ); Sat, 13 Jan 2018 13:50:52 -0500 X-Google-Smtp-Source: ACJfBotsBf5Y/I+sIWoTRywgGlT2dlCTmHOaoOqoF+Im586b6YJQ86/2O4SK9IZT7J7nGpjqu4n0Rw== Date: Sat, 13 Jan 2018 21:50:48 +0300 From: Alexey Dobriyan To: tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com Cc: x86@kernel.org, linux-kernel@vger.kernel.org, bp@suse.de Subject: [PATCH] x86_64: clobber flags in clear_page() Message-ID: <20180113185048.GA23111@avx2> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.7.2 (2016-11-26) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Return-Path: All clear_page() implementations use XOR which resets flags. Judging by allyesconfig disassembly no code is affected. Signed-off-by: Alexey Dobriyan --- arch/x86/include/asm/page_64.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/arch/x86/include/asm/page_64.h +++ b/arch/x86/include/asm/page_64.h @@ -47,7 +47,7 @@ static inline void clear_page(void *page) clear_page_erms, X86_FEATURE_ERMS, "=D" (page), "0" (page) - : "memory", "rax", "rcx"); + : "cc", "memory", "rax", "rcx"); } void copy_page(void *to, void *from);