From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marcelo Tosatti Subject: Re: [RFC] allow userspace to set MSR no-ops Date: Tue, 3 Nov 2009 13:12:03 -0200 Message-ID: <20091103151203.GA10990@amt.cnet> References: <25a1d91b0910281023u5a44576bh682ae4c59cfa7be9@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: kvm@vger.kernel.org To: David Windsor Return-path: Received: from mx1.redhat.com ([209.132.183.28]:54547 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751013AbZKCPvz (ORCPT ); Tue, 3 Nov 2009 10:51:55 -0500 Content-Disposition: inline In-Reply-To: <25a1d91b0910281023u5a44576bh682ae4c59cfa7be9@mail.gmail.com> Sender: kvm-owner@vger.kernel.org List-ID: On Wed, Oct 28, 2009 at 01:23:07PM -0400, David Windsor wrote: > Hi, > > I've encountered a situation in which I would like to allow userspace > to set the MSRs which KVM should not emulate and instead implement > these as no-ops. > > I have not seen any work in this space, furthermore there is an item > on the KVM TODO that is very similar to what I'm trying to do. > > The userspace interface is an extension of kvm_vcpu_ioctl, adding the > KVM_SET_MSRS_NOOP flag. It takes a struct kvm_msrs as a list of which > MSRs should be no-ops and adds the field noop to struct kvm_msr_entry. > This patch only affects vmx, but if the approach is sane, I can > extend it to support svm as well. Does the ignore_msrs kvm.ko parameter achieve what you want?