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=-1.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS 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 7DB5ACA90AF for ; Wed, 13 May 2020 09:09:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 575D7206A5 for ; Wed, 13 May 2020 09:09:33 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="fBEhvVHy" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732375AbgEMJJb (ORCPT ); Wed, 13 May 2020 05:09:31 -0400 Received: from us-smtp-2.mimecast.com ([207.211.31.81]:27914 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1730334AbgEMJJa (ORCPT ); Wed, 13 May 2020 05:09:30 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1589360969; 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=LkQRKl9tLygDVkb/DJW18fHZ9G4cW+Tv9HaEWtJVlFg=; b=fBEhvVHyqHtVvtmuhkPKShNonYuhsEBwy3gL6Z3TYESuzl9BbPXKwHJfThDJLxzxdr80Is /Mw3K4sKxGLgtW9pmIWS63i5Z7Jqg8RO5HhfePiikZUquQ5wGk0M2DWOnIeA4KtBV4Nr63 STGYsiy/st9yuXor7nztEBTcUws+vc8= Received: from mail-wr1-f69.google.com (mail-wr1-f69.google.com [209.85.221.69]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-453-hF79RUdkObC-n7oyGVhRag-1; Wed, 13 May 2020 05:09:27 -0400 X-MC-Unique: hF79RUdkObC-n7oyGVhRag-1 Received: by mail-wr1-f69.google.com with SMTP id 30so8349083wrq.15 for ; Wed, 13 May 2020 02:09:27 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:in-reply-to:references:date :message-id:mime-version; bh=LkQRKl9tLygDVkb/DJW18fHZ9G4cW+Tv9HaEWtJVlFg=; b=UEP5iJmooGGY2RY1jhMTWxy4rHWedPT2YWDmCNUOVCCJOezWi9T8Ftpqksw11PuZbd A5652si88d9o2KAQlmfVR6N0R3VVM+5+1EEzKOl1EaDOYu3SberHoctvUHSg8ChFoutB D7BdKhYfcM6GT5P8U/Ril5CsPq7PEFov8NFbRrOl00uned35UA/rCKATRQG/tRKLZ+y/ +b998rTizuIZg43iruyW+4zI+OiWe4BezZmWtOj3m82hyjoC1uo7Q/4qgjm0URKYy047 iXCmhw8eZQrMX4fF1sSkP3w2nrofVbH1yHUe2ESdxp7TTHeAiSfVgI5JHgrsXEWNYtM5 d+VA== X-Gm-Message-State: AGi0PuYHPYGF1OQMWPimzlamyiU89ZlgWKfFUry8C+IiqAVTB0jprCu7 pszsDz9TbAUFfXqx591bedBGX4AZMCQ6JUe71gBfHNrfLU6TJXI/iK5pluG+tWolAaAlcbMsRrY 4eM7kob82jmu4lJpjcJSkEVkE X-Received: by 2002:a1c:99d3:: with SMTP id b202mr43420406wme.126.1589360965710; Wed, 13 May 2020 02:09:25 -0700 (PDT) X-Google-Smtp-Source: APiQypIjv23QQ+2IFmFvDYhwD6Weh2biJtnHzNX52SF/bAHYC2OofdpyPGHaYJrzuFQpZNuwDeYLdw== X-Received: by 2002:a1c:99d3:: with SMTP id b202mr43420381wme.126.1589360965486; Wed, 13 May 2020 02:09:25 -0700 (PDT) Received: from vitty.brq.redhat.com (g-server-2.ign.cz. [91.219.240.2]) by smtp.gmail.com with ESMTPSA id b145sm13059757wme.41.2020.05.13.02.09.23 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 13 May 2020 02:09:24 -0700 (PDT) From: Vitaly Kuznetsov To: Sean Christopherson , Vivek Goyal Cc: kvm@vger.kernel.org, x86@kernel.org, Paolo Bonzini , Andy Lutomirski , Thomas Gleixner , Borislav Petkov , "H. Peter Anvin" , Wanpeng Li , Jim Mattson , Gavin Shan , Peter Zijlstra , linux-kernel@vger.kernel.org Subject: Re: [PATCH 2/8] KVM: x86: extend struct kvm_vcpu_pv_apf_data with token info In-Reply-To: <20200512175017.GC12100@linux.intel.com> References: <20200511164752.2158645-1-vkuznets@redhat.com> <20200511164752.2158645-3-vkuznets@redhat.com> <20200512152709.GB138129@redhat.com> <87o8qtmaat.fsf@vitty.brq.redhat.com> <20200512155339.GD138129@redhat.com> <20200512175017.GC12100@linux.intel.com> Date: Wed, 13 May 2020 11:09:23 +0200 Message-ID: <874kskmcak.fsf@vitty.brq.redhat.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Sean Christopherson writes: > > Why bother preserving backwards compatibility? AIUI, both KVM and guest > will support async #PF iff interrupt delivery is enabled. Why not make > the interrupt delivery approach KVM_ASYNC_PF_V2 and completely redefine the > ABI? E.g. to make it compatible with reflecting !PRESENT faults without a > VM-Exit via Intel's EPT Violation #VE? > That's the plan, actually. 'page not present' becomes #VE and 'page present' becomes an interrupt (we don't need to inject them synchronously). These two parts are fairly independent but can be merged to reuse the same new capability/CPUID. -- Vitaly