From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752118AbcAUVsE (ORCPT ); Thu, 21 Jan 2016 16:48:04 -0500 Received: from mail.skyhub.de ([78.46.96.112]:32891 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751276AbcAUVsC (ORCPT ); Thu, 21 Jan 2016 16:48:02 -0500 Date: Thu, 21 Jan 2016 22:47:32 +0100 From: Borislav Petkov To: "H. Peter Anvin" Cc: Huaitong Han , tglx@linutronix.de, mingo@redhat.com, david.vrabel@citrix.com, rusty@rustcorp.com.au, x86@kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH V2] x86: use enum cpuid_leafs instead of magic numbers Message-ID: <20160121214732.GM21930@pd.tnic> References: <1453374160-4648-1-git-send-email-huaitong.han@intel.com> <20160121114250.GD21930@pd.tnic> <56A147F9.1000306@zytor.com> <20160121212109.GK21930@pd.tnic> <56A14CC2.7090607@zytor.com> <20160121213309.GL21930@pd.tnic> <56A14FA0.6090700@zytor.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <56A14FA0.6090700@zytor.com> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jan 21, 2016 at 01:37:36PM -0800, H. Peter Anvin wrote: > No, you still need to be able to find the beginning of the capability > array, but the point is that right now it is implicit in that code that > CPUID_1_EDX == 0. Ah, you wanna be able to do: --- diff --git a/arch/x86/kernel/head_32.S b/arch/x86/kernel/head_32.S index af1112980dd4..143646f0add1 100644 --- a/arch/x86/kernel/head_32.S +++ b/arch/x86/kernel/head_32.S @@ -441,7 +443,7 @@ enable_paging: movb %al,X86_MODEL andb $0x0f,%cl # mask mask revision movb %cl,X86_MASK - movl %edx,X86_CAPABILITY + movl %edx,X86_CAPABILITY + CPUID_1_EDX*4 is486: movl $0x50022,%ecx # set AM, WP, NE and MP -- Regards/Gruss, Boris. ECO tip #101: Trim your mails when you reply.