From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756177Ab2AJMmI (ORCPT ); Tue, 10 Jan 2012 07:42:08 -0500 Received: from mx1.redhat.com ([209.132.183.28]:32217 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752503Ab2AJMmE (ORCPT ); Tue, 10 Jan 2012 07:42:04 -0500 Date: Tue, 10 Jan 2012 10:40:52 -0200 From: Marcelo Tosatti To: Boris Ostrovsky Cc: avi@redhat.com, Joerg.Roedel@amd.com, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, boris.ostrovsky@amd.com Subject: Re: [PATCH v2.2] KVM: SVM: Add support for AMD's OSVW feature in guests Message-ID: <20120110124052.GB31611@amt.cnet> References: <1326135635-10756-1-git-send-email-ostr@amd64.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1326135635-10756-1-git-send-email-ostr@amd64.org> 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, Jan 09, 2012 at 02:00:35PM -0500, Boris Ostrovsky wrote: > From: Boris Ostrovsky > > In some cases guests should not provide workarounds for errata even when the > physical processor is affected. For example, because of erratum 400 on family > 10h processors a Linux guest will read an MSR (resulting in VMEXIT) before > going to idle in order to avoid getting stuck in a non-C0 state. This is not > necessary: HLT and IO instructions are intercepted and therefore there is no > reason for erratum 400 workaround in the guest. > > This patch allows us to present a guest with certain errata as fixed, > regardless of the state of actual hardware. > > Signed-off-by: Boris Ostrovsky Applied, thanks.