From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mx2.redhat.com ([66.187.237.31]) by bombadil.infradead.org with esmtp (Exim 4.68 #1 (Red Hat Linux)) id 1Ky29S-0000Bi-Mr for kexec@lists.infradead.org; Thu, 06 Nov 2008 10:31:47 +0000 Message-ID: <4912C75B.8050508@redhat.com> Date: Thu, 06 Nov 2008 12:30:51 +0200 From: Avi Kivity MIME-Version: 1.0 Subject: Re: [PATCH 08/16] x86: Emergency virtualization disable function References: <1225810364-8990-1-git-send-email-ehabkost@redhat.com> <1225810364-8990-9-git-send-email-ehabkost@redhat.com> <20081105175235.GJ5247@blackpad> <4912BD67.8000704@redhat.com> In-Reply-To: List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: kexec-bounces@lists.infradead.org Errors-To: kexec-bounces+dwmw2=infradead.org@lists.infradead.org To: "Eric W. Biederman" Cc: Andrew Morton , Eduardo Habkost , kvm@vger.kernel.org, kexec@lists.infradead.org, linux-kernel@vger.kernel.org, "Rafael J. Wysocki" , Haren Myneni , Simon Horman , Ingo Molnar , Andrey Borzenkov , mingo@redhat.com, Vivek Goyal Eric W. Biederman wrote: > >> If you want to be extra simple and safe, remove kvm from the equation. Make the >> disabling code part of kdump/emergency_restart and only rely on the convention >> that cr3.vmxe == vmxon. >> > Convention? > There is a de-facto convention supported by at least vmware and kvm. If cr4.vmxe is 1, then we are in vmx operation. If cr4.vmxe is 0, then we are not in vmx operation. This allows us to determine whether we need to execute vmxoff without any APIs. -- error compiling committee.c: too many arguments to function _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754924AbYKFKc1 (ORCPT ); Thu, 6 Nov 2008 05:32:27 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753553AbYKFKcO (ORCPT ); Thu, 6 Nov 2008 05:32:14 -0500 Received: from mx2.redhat.com ([66.187.237.31]:33016 "EHLO mx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752589AbYKFKcN (ORCPT ); Thu, 6 Nov 2008 05:32:13 -0500 Message-ID: <4912C75B.8050508@redhat.com> Date: Thu, 06 Nov 2008 12:30:51 +0200 From: Avi Kivity User-Agent: Thunderbird 2.0.0.16 (X11/20080723) MIME-Version: 1.0 To: "Eric W. Biederman" CC: Eduardo Habkost , Ingo Molnar , Simon Horman , Andrew Morton , Vivek Goyal , Haren Myneni , Andrey Borzenkov , mingo@redhat.com, "Rafael J. Wysocki" , kexec@lists.infradead.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 08/16] x86: Emergency virtualization disable function References: <1225810364-8990-1-git-send-email-ehabkost@redhat.com> <1225810364-8990-9-git-send-email-ehabkost@redhat.com> <20081105175235.GJ5247@blackpad> <4912BD67.8000704@redhat.com> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Eric W. Biederman wrote: > >> If you want to be extra simple and safe, remove kvm from the equation. Make the >> disabling code part of kdump/emergency_restart and only rely on the convention >> that cr3.vmxe == vmxon. >> > Convention? > There is a de-facto convention supported by at least vmware and kvm. If cr4.vmxe is 1, then we are in vmx operation. If cr4.vmxe is 0, then we are not in vmx operation. This allows us to determine whether we need to execute vmxoff without any APIs. -- error compiling committee.c: too many arguments to function From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: [PATCH 08/16] x86: Emergency virtualization disable function Date: Thu, 06 Nov 2008 12:30:51 +0200 Message-ID: <4912C75B.8050508@redhat.com> References: <1225810364-8990-1-git-send-email-ehabkost@redhat.com> <1225810364-8990-9-git-send-email-ehabkost@redhat.com> <20081105175235.GJ5247@blackpad> <4912BD67.8000704@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: Andrew Morton , Eduardo Habkost , kvm-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, kexec-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, "Rafael J. Wysocki" , Haren Myneni , Simon Horman , Ingo Molnar , Andrey Borzenkov , mingo-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, Vivek Goyal To: "Eric W. Biederman" Return-path: In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: kexec-bounces-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org Errors-To: kexec-bounces+glkk-kexec=m.gmane.org-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org List-Id: kvm.vger.kernel.org Eric W. Biederman wrote: > >> If you want to be extra simple and safe, remove kvm from the equation. Make the >> disabling code part of kdump/emergency_restart and only rely on the convention >> that cr3.vmxe == vmxon. >> > Convention? > There is a de-facto convention supported by at least vmware and kvm. If cr4.vmxe is 1, then we are in vmx operation. If cr4.vmxe is 0, then we are not in vmx operation. This allows us to determine whether we need to execute vmxoff without any APIs. -- error compiling committee.c: too many arguments to function