Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754091Ab3DSTLl (ORCPT ); Fri, 19 Apr 2013 15:11:41 -0400 Received: from mail.skyhub.de ([78.46.96.112]:51648 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753655Ab3DSTLj (ORCPT ); Fri, 19 Apr 2013 15:11:39 -0400 Date: Fri, 19 Apr 2013 21:11:28 +0200 From: Borislav Petkov To: "Bryan O'Donoghue" Cc: hpa@zytor.com, linux-kernel@vger.kernel.org, x86@kernel.org, fenghua.yu@intel.com Subject: Re: [PATCH] x86: Add check for P5 to microcode_intel_early Message-ID: <20130419191128.GA21991@pd.tnic> References: <1366392183-4149-1-git-send-email-bryan.odonoghue.lkml@nexus-software.ie> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <1366392183-4149-1-git-send-email-bryan.odonoghue.lkml@nexus-software.ie> 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 Content-Length: 970 Lines: 26 On Fri, Apr 19, 2013 at 06:23:03PM +0100, Bryan O'Donoghue wrote: > Architectural MSRs associated with microcode are for P6 or higher. > Add a check to early microcode to detect < P6. > > Without a check for < P6 - we end up reading from unimplemented MSRs > on Pentium. Is this something you're actually seeing on some box or just found by staring at the code? In any case, the family checks should go into the ucode driver entry points in arch/x86/kernel/microcode_core_early.c. AFAICT, x86_vendor() is a good candidate to be taught to read out the family too and return X86_VENDOR_UNKNOWN if < P6. Or something to that effect. -- Regards/Gruss, Boris. Sent from a fat crate under my desk. Formatting is fine. -- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/