From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, HK_RANDOM_FROM,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7419FC3A59E for ; Thu, 5 Sep 2019 01:11:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5400420870 for ; Thu, 5 Sep 2019 01:11:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730074AbfIEBL6 (ORCPT ); Wed, 4 Sep 2019 21:11:58 -0400 Received: from mga04.intel.com ([192.55.52.120]:56241 "EHLO mga04.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727162AbfIEBL5 (ORCPT ); Wed, 4 Sep 2019 21:11:57 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga007.jf.intel.com ([10.7.209.58]) by fmsmga104.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 04 Sep 2019 18:11:57 -0700 X-IronPort-AV: E=Sophos;i="5.64,468,1559545200"; d="scan'208";a="173767401" Received: from xiaoyaol-mobl.ccr.corp.intel.com (HELO [10.239.13.123]) ([10.239.13.123]) by orsmga007-auth.jf.intel.com with ESMTP/TLS/AES256-SHA; 04 Sep 2019 18:11:55 -0700 Subject: Re: [PATCH v2] doc: kvm: Fix return description of KVM_SET_MSRS To: Sean Christopherson Cc: Paolo Bonzini , =?UTF-8?B?UmFkaW0gS3LEjW3DocWZ?= , Jonathan Corbet , kvm@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org References: <20190904060118.43851-1-xiaoyao.li@intel.com> <20190904174122.GK24079@linux.intel.com> From: Xiaoyao Li Message-ID: <5e61463e-b389-4393-81f9-a154ee4688be@intel.com> Date: Thu, 5 Sep 2019 09:11:53 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: <20190904174122.GK24079@linux.intel.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 9/5/2019 1:41 AM, Sean Christopherson wrote: > On Wed, Sep 04, 2019 at 02:01:18PM +0800, Xiaoyao Li wrote: >> Userspace can use ioctl KVM_SET_MSRS to update a set of MSRs of guest. >> This ioctl sets specified MSRs one by one. Once it fails to set an MSR >> due to setting reserved bits, the MSR is not supported/emulated by kvm, >> or violating other restrictions, it stops further processing and returns >> the number of MSRs have been set successfully. >> >> Signed-off-by: Xiaoyao Li >> --- >> v2: >> elaborate the changelog and description of ioctl KVM_SET_MSRS based on >> Sean's comments. >> >> --- >> Documentation/virt/kvm/api.txt | 7 ++++++- >> 1 file changed, 6 insertions(+), 1 deletion(-) >> >> diff --git a/Documentation/virt/kvm/api.txt b/Documentation/virt/kvm/api.txt >> index 2d067767b617..4638e893dec0 100644 >> --- a/Documentation/virt/kvm/api.txt >> +++ b/Documentation/virt/kvm/api.txt >> @@ -586,7 +586,7 @@ Capability: basic >> Architectures: x86 >> Type: vcpu ioctl >> Parameters: struct kvm_msrs (in) >> -Returns: 0 on success, -1 on error >> +Returns: number of msrs successfully set (see below), -1 on error >> >> Writes model-specific registers to the vcpu. See KVM_GET_MSRS for the >> data structures. >> @@ -595,6 +595,11 @@ Application code should set the 'nmsrs' member (which indicates the >> size of the entries array), and the 'index' and 'data' members of each >> array entry. >> >> +It tries to set the MSRs in array entries[] one by one. Once failing to > > Probably better to say 'If' as opposed to 'Once', don't want to imply that > userspace is incompetent :) > >> +set an MSR (due to setting reserved bits, the MSR is not supported/emulated >> +by kvm, or violating other restrctions), > > Make it clear the list is not exhaustive, e.g.: > > It tries to set the MSRs in array entries[] one by one. If setting an MSR > fails, e.g. due to setting reserved bits, the MSR isn't supported/emulated by > KVM, etc..., it stops processing the MSR list and returns the number of MSRs > that have been set successfully. > Refine it as you commented and send out v3, thanks. >> it stops setting following MSRs >> +and returns the number of MSRs have been set successfully. >> + >> >> 4.20 KVM_SET_CPUID >> >> -- >> 2.19.1 >>