From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S966475Ab3DQOIs (ORCPT ); Wed, 17 Apr 2013 10:08:48 -0400 Received: from nat28.tlf.novell.com ([130.57.49.28]:33311 "EHLO nat28.tlf.novell.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S966393Ab3DQOIr convert rfc822-to-8bit (ORCPT ); Wed, 17 Apr 2013 10:08:47 -0400 Message-Id: <516EC93D02000078000CE30A@nat28.tlf.novell.com> X-Mailer: Novell GroupWise Internet Agent 12.0.2 Date: Wed, 17 Apr 2013 15:09:33 +0100 From: "Jan Beulich" To: "Michael S. Tsirkin" Cc: "olaf@aepfle.de" , "bp@alien8.de" , "apw@canonical.com" , "x86@kernel.org" , "tglx@linutronix.de" , "devel@linuxdriverproject.org" , "gregkh@linuxfoundation.org" , "KY Srinivasan" , "jasowang@redhat.com" , "linux-kernel@vger.kernel.org" , "hpa@zytor.com" Subject: Re: [PATCH 2/3] X86: Add a check to catch Xen emulation of Hyper-V References: <1359940910-32114-1-git-send-email-kys@microsoft.com> <1359940959-32168-1-git-send-email-kys@microsoft.com> <1359940959-32168-2-git-send-email-kys@microsoft.com> <20130417070616.GA4487@redhat.com> <423ae84de75f4b3587eb2d1a365cbd95@SN2PR03MB061.namprd03.prod.outlook.com> <516EC54A02000078000CE2AE@nat28.tlf.novell.com> <20130417130102.GE6801@redhat.com> In-Reply-To: <20130417130102.GE6801@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 8BIT Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org >>> On 17.04.13 at 15:01, "Michael S. Tsirkin" wrote: > On Wed, Apr 17, 2013 at 02:52:42PM +0100, Jan Beulich wrote: >> >>> On 17.04.13 at 15:20, KY Srinivasan wrote: >> > If I recall correctly, the issue here was that Xen was enabling Hyper-V >> > emulation un-conditionally even for Linux guests. >> >> To make this a little more precise - Xen is doing so only when the >> guest config tells it to. > > So it's something explicitly requested for this guest? Then I don't > understand why does not make sense to override it in guest. Iirc it was/is XenServer which enable Hyper-V emulation for all HVM guests, which clearly is the wrong thing. I was personally also not really in agreement with the override in the kernel, but it was decided to do it that way at that point in time. As a consequence, I don't object this to be reverted. Jan