From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752841AbdF0NTv (ORCPT ); Tue, 27 Jun 2017 09:19:51 -0400 Received: from mail-wr0-f196.google.com ([209.85.128.196]:33582 "EHLO mail-wr0-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751659AbdF0NTp (ORCPT ); Tue, 27 Jun 2017 09:19:45 -0400 Subject: Re: [PATCH v5 4/4] KVM: async_pf: Let host know whether the guest support delivery async_pf as #PF vmexit To: Wanpeng Li , linux-kernel@vger.kernel.org, kvm@vger.kernel.org Cc: =?UTF-8?B?UmFkaW0gS3LEjW3DocWZ?= , Wanpeng Li References: <1498528021-5115-1-git-send-email-wanpeng.li@hotmail.com> <1498528021-5115-5-git-send-email-wanpeng.li@hotmail.com> From: Paolo Bonzini Message-ID: Date: Tue, 27 Jun 2017 15:19:41 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.2.0 MIME-Version: 1.0 In-Reply-To: <1498528021-5115-5-git-send-email-wanpeng.li@hotmail.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 27/06/2017 03:47, Wanpeng Li wrote: > - wrmsrl(MSR_KVM_ASYNC_PF_EN, pa | KVM_ASYNC_PF_ENABLED); > + pa |= KVM_ASYNC_PF_DELIVERY_AS_PF_VMEXIT | KVM_ASYNC_PF_ENABLED; > + wrmsr_safe(MSR_KVM_ASYNC_PF_EN, pa & 0xffffffff, pa >> 32); > __this_cpu_write(apf_reason.enabled, 1); Better: pa |= KVM_ASYNC_PF_ENABLED; /* Async page fault support for L1 hypervisor is optional. */ if (wrmsr_safe(MSR_KVM_ASYNC_PF_EN, pa | KVM_ASYNC_PF_DELIVERY_AS_PF_VMEXIT) < 0) wrmsrl(MSR_KVM_ASYNC_PF_EN, pa); Thanks, Paolo