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=-14.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1,USER_IN_DEF_DKIM_WL autolearn=no 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 0B55BC433B4 for ; Wed, 21 Apr 2021 11:16:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D37F961424 for ; Wed, 21 Apr 2021 11:16:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238681AbhDULQf (ORCPT ); Wed, 21 Apr 2021 07:16:35 -0400 Received: from linux.microsoft.com ([13.77.154.182]:42908 "EHLO linux.microsoft.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235951AbhDULQa (ORCPT ); Wed, 21 Apr 2021 07:16:30 -0400 Received: from [192.168.86.31] (c-73-38-52-84.hsd1.vt.comcast.net [73.38.52.84]) by linux.microsoft.com (Postfix) with ESMTPSA id DC78B20B8001; Wed, 21 Apr 2021 04:15:55 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com DC78B20B8001 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1619003757; bh=0lGPWgCWxMY7QAIfAJHFkFTAYipH0FMtf/PdmxPyrUw=; h=Subject:To:Cc:References:From:Date:In-Reply-To:From; b=gudX5C8+viqc/m58ZbDfBIGMK5DF+vGWywf/UQuUq+w1S+fUI8PZmcpVYd9Zhl71G 7V5SefAQZ34ieq6v2Vd8FjSDLntWCzHUMWa3sIdlqQpijXqElS6Ied6EMj3YoGLLjf JG9H08F28TC64nZMQQiYrs63e9IN3gNQlH1Xp1o0= Subject: Re: [PATCH v2 2/7] hyperv: SVM enlightened TLB flush support flag To: Wei Liu Cc: Lan Tianyu , Michael Kelley , Paolo Bonzini , Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , Stephen Hemminger , Haiyang Zhang , "H. Peter Anvin" , Thomas Gleixner , Ingo Molnar , Borislav Petkov , "K. Y. Srinivasan" , x86@kernel.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-hyperv@vger.kernel.org, viremana@linux.microsoft.com References: <3fd0cdfb9a4164a3fb90351db4dc10f52a7c4819.1618492553.git.viremana@linux.microsoft.com> <20210421100026.4hcgrxeri444if45@liuwe-devbox-debian-v2> From: Vineeth Pillai Message-ID: <4a57cd2b-43b5-2625-3663-449ffa715b51@linux.microsoft.com> Date: Wed, 21 Apr 2021 07:15:54 -0400 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.7.1 MIME-Version: 1.0 In-Reply-To: <20210421100026.4hcgrxeri444if45@liuwe-devbox-debian-v2> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 4/21/21 6:00 AM, Wei Liu wrote: > On Thu, Apr 15, 2021 at 01:43:37PM +0000, Vineeth Pillai wrote: >> >> +/* >> + * This is specific to AMD and specifies that enlightened TLB flush is >> + * supported. If guest opts in to this feature, ASID invalidations only >> + * flushes gva -> hpa mapping entries. To flush the TLB entries derived >> + * from NPT, hypercalls should be used (HvFlushGuestPhysicalAddressSpace >> + * or HvFlushGuestPhysicalAddressList). >> + */ >> +#define HV_X64_NESTED_ENLIGHTENED_TLB BIT(22) >> + > c > This is not yet documented in TLFS, right? I can't find this bit in the > latest edition (6.0b). This would be documented in the TLFS update which is soon to be released. > > My first thought is the comment says this is AMD specific but the name > is rather generic. That looks a bit odd to begin with. I thought of of keeping the name generic to avoid renaming Intel specific ones also. If I understand correctly, the TLFS would also be having generic name for this and just translated the generic name here in this header. Thanks, Vineeth