From mboxrd@z Thu Jan 1 00:00:00 1970 From: Paolo Bonzini Subject: Re: [PATCH] KVM: add KVM_CAP_VMX_APICV to advertise hardware apic-v support Date: Thu, 18 Dec 2014 09:30:15 +0100 Message-ID: <54929097.4000806@redhat.com> References: <1418285221-14256-1-git-send-email-zhang.zhanghailiang@huawei.com> <548993D8.6010004@huawei.com> <5489D13B.3000703@redhat.com> <5914325.jABlNffIti@k> <54924BE2.7070806@huawei.com> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Cc: hangaohuai@huawei.com, kvm@vger.kernel.org, gleb@kernel.org, peter.huangpeng@huawei.com To: zhanghailiang , Stefan Fritsch Return-path: Received: from mail-wg0-f50.google.com ([74.125.82.50]:60707 "EHLO mail-wg0-f50.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752077AbaLRIaU (ORCPT ); Thu, 18 Dec 2014 03:30:20 -0500 Received: by mail-wg0-f50.google.com with SMTP id a1so940436wgh.9 for ; Thu, 18 Dec 2014 00:30:19 -0800 (PST) In-Reply-To: <54924BE2.7070806@huawei.com> Sender: kvm-owner@vger.kernel.org List-ID: On 18/12/2014 04:37, zhanghailiang wrote: >> set this bit. But the HV_X64_APIC_ACCESS_RECOMMENDED bit should >> probably not be set if the host supports apic-v. I havn't done any > > That is what this patch want to do ;) This would cause a guest ABI change upon migration from APICv to non-APICv hosts, so it is not possible. Perhaps we need to set bit 8 but not bit 3. Paolo