Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758549AbcLAJWe (ORCPT ); Thu, 1 Dec 2016 04:22:34 -0500 Received: from mail.skyhub.de ([78.46.96.112]:41427 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750873AbcLAJWc (ORCPT ); Thu, 1 Dec 2016 04:22:32 -0500 Date: Thu, 1 Dec 2016 10:22:28 +0100 From: Borislav Petkov To: Andy Lutomirski Cc: x86@kernel.org, One Thousand Gnomes , "linux-kernel@vger.kernel.org" , Brian Gerst , Matthew Whitehead , Henrique de Moraes Holschuh Subject: Re: [PATCH 4/4] x86/asm: Change sync_core() to use MOV to CR2 to serialize Message-ID: <20161201092228.calajwwv4k4k4l6f@pd.tnic> References: <46816abe4f68ac3eb9b80231bf64ba8edcebc2f7.1480536936.git.luto@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <46816abe4f68ac3eb9b80231bf64ba8edcebc2f7.1480536936.git.luto@kernel.org> User-Agent: NeoMutt/20161014 (1.7.1) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 734 Lines: 21 On Wed, Nov 30, 2016 at 12:34:55PM -0800, Andy Lutomirski wrote: > Aside from being excessively slow, CPUID is problematic: Linux runs > on a handful of CPUs that don't have CPUID. MOV to CR2 is always > available, so use it instead. > > Signed-off-by: Andy Lutomirski > --- > arch/x86/include/asm/processor.h | 31 ++++++++----------------------- > 1 file changed, 8 insertions(+), 23 deletions(-) Looks nice. I'm wondering if we should leave this one in tip for an additional cycle to have it tested on more hw. I know, it is architectural and so on but who knows what every implementation actually does... -- Regards/Gruss, Boris. Good mailing practices for 400: avoid top-posting and trim the reply.