From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on archive.lwn.net X-Spam-Level: X-Spam-Status: No, score=-6.0 required=5.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI,SPF_HELO_NONE,SPF_NONE autolearn=ham autolearn_force=no version=3.4.2 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by archive.lwn.net (Postfix) with ESMTP id 495577D2EF for ; Wed, 29 May 2019 03:12:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726304AbfE2DMR (ORCPT ); Tue, 28 May 2019 23:12:17 -0400 Received: from mga17.intel.com ([192.55.52.151]:41169 "EHLO mga17.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725816AbfE2DMQ (ORCPT ); Tue, 28 May 2019 23:12:16 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga003.jf.intel.com ([10.7.209.27]) by fmsmga107.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 28 May 2019 20:12:16 -0700 X-ExtLoop1: 1 Received: from txu2-mobl.ccr.corp.intel.com (HELO [10.239.196.245]) ([10.239.196.245]) by orsmga003.jf.intel.com with ESMTP; 28 May 2019 20:12:13 -0700 Subject: Re: [PATCH v2 1/3] KVM: x86: add support for user wait instructions To: Paolo Bonzini Cc: rkrcmar@redhat.com, corbet@lwn.net, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, hpa@zytor.com, sean.j.christopherson@intel.com, x86@kernel.org, kvm@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, jingqi.liu@intel.com References: <20190524075637.29496-1-tao3.xu@intel.com> <20190524075637.29496-2-tao3.xu@intel.com> <419f62f3-69a8-7ec0-5eeb-20bed69925f2@redhat.com> From: Tao Xu Message-ID: Date: Wed, 29 May 2019 11:12:12 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.7.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-doc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org On 5/29/2019 10:38 AM, Paolo Bonzini wrote: > On 29/05/19 04:05, Tao Xu wrote: >>> >> >> Thank you Paolo, but I have another question. I was wondering if it is >> appropriate to enable X86_FEATURE_WAITPKG when QEMU uses "-overcommit >> cpu-pm=on"? > > "-overcommit" only establishes the behavior of KVM, it doesn't change > the cpuid bits. So you'd need "-cpu" as well. > > Paolo > OK I got it. Thank you for your review.