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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 20911C32774 for ; Mon, 22 Aug 2022 16:24:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233351AbiHVQYt (ORCPT ); Mon, 22 Aug 2022 12:24:49 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44206 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235896AbiHVQYq (ORCPT ); Mon, 22 Aug 2022 12:24:46 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1976F402E6 for ; Mon, 22 Aug 2022 09:24:44 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1661185484; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=z+8JZGtkVxOmbIeQgHkw8hE6eGekXQYn3qmLX4nEH6U=; b=V20Jqrdc7BnugIBn6lnu7DJJ4hLLqgoUJlwifJpewMZrwiMcdrhfCNBrtbV6c08lRl61q3 ki/u8D5MurtroLqft84sH8pYZuLJJMnYRdYUkeiguy5bquuSoxsMfplkEye0azQd+Etl0h /CFBqgAsBsc3/Aur5HM+N/0yuunlo7w= Received: from mail-wm1-f69.google.com (mail-wm1-f69.google.com [209.85.128.69]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_128_GCM_SHA256) id us-mta-65-XuK-KVClNGKQs71XbPHsJg-1; Mon, 22 Aug 2022 12:24:42 -0400 X-MC-Unique: XuK-KVClNGKQs71XbPHsJg-1 Received: by mail-wm1-f69.google.com with SMTP id m22-20020a7bca56000000b003a652939bd1so698800wml.9 for ; Mon, 22 Aug 2022 09:24:42 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=mime-version:message-id:date:references:in-reply-to:subject:cc:to :from:x-gm-message-state:from:to:cc; bh=z+8JZGtkVxOmbIeQgHkw8hE6eGekXQYn3qmLX4nEH6U=; b=BM49eAwQInkvyCx3wMNEdlywWaxkS1GUHTRCeiQBJ9km0HHEjbsoo+Z4dEpuep+0Gy 124py1drDO+LDmwrOekMXXap7BA0iaqdKEqzwLf7clVyWa/VRuuaUsNvUJpehevMhYSo bhWW4WwMjnu7GQc5LF7NwInUWkg5cVgcYduWxuKZkx0nZ5OjttbpBKd0Rtgi3Ob/p/Gw cdiLJadg6xfNZEs2FZr9yCtMTYXvW3/P0k+orNIhiCC0IEPH8KnMxjky524BPN6M+t2c 4sWJOY/gLQ9Z/mUmOAPTflmO0vCqQs2v9ixLudwhwsjj+dFBkDZv5peTEw92qS2pNPGO MlUw== X-Gm-Message-State: ACgBeo1UVHfgeGHbMm8NCRAAeITOYOnvktZtnLVsRGeDsfl8KYigAWpP S7LcyzLKsxrukc6WGlJlLGFRPAj/dNCHZ8R+Y3PN9uVR3nUOishXfqByLRGXr6ghXYbWPkzz7fm ZMNGuCyCkSeDC X-Received: by 2002:a05:600c:4c21:b0:3a5:3c02:5f83 with SMTP id d33-20020a05600c4c2100b003a53c025f83mr12938078wmp.7.1661185481842; Mon, 22 Aug 2022 09:24:41 -0700 (PDT) X-Google-Smtp-Source: AA6agR4JktIIM3YnkZ0hZg4t+vSbZRizc51oECyEp4vgtwebh5kaTgN4SZT2vRicR3YFSKegjL7eRQ== X-Received: by 2002:a05:600c:4c21:b0:3a5:3c02:5f83 with SMTP id d33-20020a05600c4c2100b003a53c025f83mr12938064wmp.7.1661185481675; Mon, 22 Aug 2022 09:24:41 -0700 (PDT) Received: from fedora (nat-2.ign.cz. [91.219.240.2]) by smtp.gmail.com with ESMTPSA id b18-20020a5d6352000000b002252751629dsm11907400wrw.24.2022.08.22.09.24.40 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 22 Aug 2022 09:24:41 -0700 (PDT) From: Vitaly Kuznetsov To: Sean Christopherson Cc: kvm@vger.kernel.org, Paolo Bonzini , Anirudh Rayabharam , Wanpeng Li , Jim Mattson , Maxim Levitsky , Nathan Chancellor , Michael Kelley , linux-hyperv@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v5 03/26] x86/hyperv: Update 'struct hv_enlightened_vmcs' definition In-Reply-To: References: <20220802160756.339464-1-vkuznets@redhat.com> <20220802160756.339464-4-vkuznets@redhat.com> <875yiptvsc.fsf@redhat.com> <87czcsskkj.fsf@redhat.com> Date: Mon, 22 Aug 2022 18:24:40 +0200 Message-ID: <87bkscxn3r.fsf@redhat.com> MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Sean Christopherson writes: > On Mon, Aug 22, 2022, Vitaly Kuznetsov wrote: >> So I reached out to Microsoft and their answer was that for all these new >> eVMCS fields (including *PerfGlobalCtrl) observing architectural VMX >> MSRs should be enough. *PerfGlobalCtrl case is special because of Win11 >> bug (if we expose the feature in VMX feature MSRs but don't set >> CPUID.0x4000000A.EBX BIT(0) it just doesn't boot). > > Does this mean that KVM-on-HyperV needs to avoid using the PERF_GLOBAL_CTRL fields > when the bit is not set? It doesn't have to, based on the reply I got from Microsoft, if PERF_GLOBAL_CTRL is exposed in architectural VMX feature MSRs than eVMCS fields are guaranteed to be present. The PV bit is 'extra'. -- Vitaly