From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753388Ab1BBU5L (ORCPT ); Wed, 2 Feb 2011 15:57:11 -0500 Received: from mail.skyhub.de ([78.46.96.112]:46746 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753177Ab1BBU5K (ORCPT ); Wed, 2 Feb 2011 15:57:10 -0500 Date: Wed, 2 Feb 2011 21:57:05 +0100 From: Borislav Petkov To: "H. Peter Anvin" Cc: Jeremy Fitzhardinge , Ingo Molnar , the arch/x86 maintainers , Linux Kernel Mailing List , Xen Devel , Jeremy Fitzhardinge Subject: Re: [PATCH 0/2] x86/microcode: support for microcode update in Xen dom0 Message-ID: <20110202205704.GA14752@liondog.tnic> Mail-Followup-To: Borislav Petkov , "H. Peter Anvin" , Jeremy Fitzhardinge , Ingo Molnar , the arch/x86 maintainers , Linux Kernel Mailing List , Xen Devel , Jeremy Fitzhardinge References: <20110130113356.GA27967@liondog.tnic> <4D461FB9.5050807@goop.org> <20110131070241.GA22071@liondog.tnic> <4D46FC9F.6090309@goop.org> <20110131234131.GA16095@liondog.tnic> <4D475099.1080004@goop.org> <4D475DB5.1020300@zytor.com> <4D488EB1.9020803@goop.org> <4D49B5F6.5010606@zytor.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <4D49B5F6.5010606@zytor.com> User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Feb 02, 2011 at 11:52:22AM -0800, H. Peter Anvin wrote: > 3. Arguably on native hardware we should still load the microcode into > RAM in the boot loader, and install it on the very early CPU bringup > path. That means locking down some (currently) 400K of RAM to handle > different combinations of CPUs, or the additional complexity of > jettisoning microcode which cannot be used while still be able to deal > with hotplug. I think there is a strong case for this model, which > would mean moving the microcode into /boot anyway. /me like it, sounds very nifty. So how do we want to do that, we add a field to the real-mode kernel header that tells us where to find the microcode image and we take it and apply the ucode somewhere in do_boot_cpu() path? -- Regards/Gruss, Boris. From mboxrd@z Thu Jan 1 00:00:00 1970 From: Borislav Petkov Subject: Re: [PATCH 0/2] x86/microcode: support for microcode update in Xen dom0 Date: Wed, 2 Feb 2011 21:57:05 +0100 Message-ID: <20110202205704.GA14752@liondog.tnic> References: <20110130113356.GA27967@liondog.tnic> <4D461FB9.5050807@goop.org> <20110131070241.GA22071@liondog.tnic> <4D46FC9F.6090309@goop.org> <20110131234131.GA16095@liondog.tnic> <4D475099.1080004@goop.org> <4D475DB5.1020300@zytor.com> <4D488EB1.9020803@goop.org> <4D49B5F6.5010606@zytor.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Return-path: Content-Disposition: inline In-Reply-To: <4D49B5F6.5010606@zytor.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: "H. Peter Anvin" Cc: Jeremy Fitzhardinge , Xen Devel , the arch/x86 maintainers , Linux Kernel Mailing List , Jeremy Fitzhardinge , Ingo Molnar List-Id: xen-devel@lists.xenproject.org On Wed, Feb 02, 2011 at 11:52:22AM -0800, H. Peter Anvin wrote: > 3. Arguably on native hardware we should still load the microcode into > RAM in the boot loader, and install it on the very early CPU bringup > path. That means locking down some (currently) 400K of RAM to handle > different combinations of CPUs, or the additional complexity of > jettisoning microcode which cannot be used while still be able to deal > with hotplug. I think there is a strong case for this model, which > would mean moving the microcode into /boot anyway. /me like it, sounds very nifty. So how do we want to do that, we add a field to the real-mode kernel header that tells us where to find the microcode image and we take it and apply the ucode somewhere in do_boot_cpu() path? -- Regards/Gruss, Boris.