From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758175Ab3BKRPs (ORCPT ); Mon, 11 Feb 2013 12:15:48 -0500 Received: from mail.skyhub.de ([78.46.96.112]:57872 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757740Ab3BKRPq (ORCPT ); Mon, 11 Feb 2013 12:15:46 -0500 Date: Mon, 11 Feb 2013 18:15:41 +0100 From: Borislav Petkov To: "H. Peter Anvin" Cc: X86 ML , LKML , Borislav Petkov Subject: Re: [PATCH 3/4] x86, head_32: Remove second CPUID detection from default_entry Message-ID: <20130211171541.GD2683@pd.tnic> Mail-Followup-To: Borislav Petkov , "H. Peter Anvin" , X86 ML , LKML , Borislav Petkov References: <1360592538-10643-1-git-send-email-bp@alien8.de> <1360592538-10643-4-git-send-email-bp@alien8.de> <18557aed-383a-4454-8222-3d2c0f0a78be@email.android.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <18557aed-383a-4454-8222-3d2c0f0a78be@email.android.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Feb 11, 2013 at 07:49:14AM -0800, H. Peter Anvin wrote: > What about CPUs with inconsistent cpuid levels? Yes, they can and do > happen, as we discussed on IRC. Yes, this should still work. We're doing the EFLAGS.ID dance right at the beginning of default_entry on each cpu and cache cpuld level in new_cpu_data for the time we're in this code. What this particular patch removes is the yet-another EFLAGS.ID dance which we IMHO unnecessarily did after enabling paging. So basically nothing changes wrt handling inconsistent cpuid levels and MSR mis-programming - we still should be taking care of those cases. Thanks. -- Regards/Gruss, Boris. Sent from a fat crate under my desk. Formatting is fine. --