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 94CEEC433F5 for ; Tue, 3 May 2022 15:04:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237779AbiECPIS (ORCPT ); Tue, 3 May 2022 11:08:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33362 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237762AbiECPIP (ORCPT ); Tue, 3 May 2022 11:08:15 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 7FDCD3A1BD for ; Tue, 3 May 2022 08:04:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1651590282; 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=q8KRyeOIJowwgq1LjuL92i0OyzQpFO6OlQ5jrqBwiaQ=; b=GsN2aHEwmnBSqzAAnCWcw7/CJDPv9Fb4L16x/+QNOcdLl9DQOTNve0c9FT4xDsQVSfgIwr aM9cVdd3W5HKV1WkonLjRzAHci+BYJSoVIYTI+HQpiEHA8hy//YAeUNr+HrZ7XRw03fE8e jrjEEt+cw4VBBg8OqyKWAeg+XDx+JJ8= Received: from mail-wm1-f71.google.com (mail-wm1-f71.google.com [209.85.128.71]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-515-El3JyjaEMFiFqjRBhvUOMQ-1; Tue, 03 May 2022 11:01:22 -0400 X-MC-Unique: El3JyjaEMFiFqjRBhvUOMQ-1 Received: by mail-wm1-f71.google.com with SMTP id c62-20020a1c3541000000b0038ec265155fso1475155wma.6 for ; Tue, 03 May 2022 08:01:21 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:in-reply-to:references:date :message-id:mime-version; bh=q8KRyeOIJowwgq1LjuL92i0OyzQpFO6OlQ5jrqBwiaQ=; b=MPxtVmU9TXCzlfICfpo5fW0/37rd+l5l7O/mDsoAC6Jv9Y3Z/5PVgn9urVFa0yc2Al NOKAvLBXd2EVVGM/khMdDa4B4vmQDLfKlCc6an41shsbTvD0CPk6lj5bs4ImE7FnAr7/ w3uvh64g22XbA0nWegFks4D07rEZ5dc31AdLno7I1ewC7SC40/xLh1KxZ1b6oumijOMk O+BykDk1yN0G8aQi+O6acyHqEACdMcz0MR2/hwYDM6H41YKaUgu4DfOhdMctvLYmtgWR /PFMZNZF5FCtbZ2QqP8SQPifJGAR8x+wQ2UxoxnSvzsXe+YMZEFKlorD5tLpK6Gqo3bp A8uQ== X-Gm-Message-State: AOAM533I3K+67H9wyFL6p5QXHn6R43su/g9wAowd9U7xhDLTaXnQBTl2 PD52IVmtG6BIGQ7EsFwyiLiDXXYYLXvU6qJXmWzbtjpHLwXPuKYg86hWNkXR09t5+2h/mbwzWCk bNjN9BSMHKGA2ioPnnTwJRha5ugZ61nOrQYnRwcex3Z9AyH5Xwfntde0V7Vs8npnBeDqQVdcJIv j4 X-Received: by 2002:a5d:64c1:0:b0:20c:6ff9:3a61 with SMTP id f1-20020a5d64c1000000b0020c6ff93a61mr4770689wri.709.1651590080963; Tue, 03 May 2022 08:01:20 -0700 (PDT) X-Google-Smtp-Source: ABdhPJyFddadb0RhMqbED3cKhIrdL1UAliMUxLFrwK6VNOQYuEXW0q5ELPbxKJShs+8DVKmBmOBFgQ== X-Received: by 2002:a5d:64c1:0:b0:20c:6ff9:3a61 with SMTP id f1-20020a5d64c1000000b0020c6ff93a61mr4770661wri.709.1651590080743; Tue, 03 May 2022 08:01:20 -0700 (PDT) Received: from fedora (nat-2.ign.cz. [91.219.240.2]) by smtp.gmail.com with ESMTPSA id t1-20020adfba41000000b0020c6fa5a797sm3344358wrg.91.2022.05.03.08.01.19 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 03 May 2022 08:01:20 -0700 (PDT) From: Vitaly Kuznetsov To: kvm@vger.kernel.org, Paolo Bonzini Cc: Sean Christopherson , Wanpeng Li , Jim Mattson , Michael Kelley , Siddharth Chandrasekaran , linux-hyperv@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v3 00/34] KVM: x86: hyper-v: Fine-grained TLB flush + L2 TLB flush feature In-Reply-To: <20220414132013.1588929-1-vkuznets@redhat.com> References: <20220414132013.1588929-1-vkuznets@redhat.com> Date: Tue, 03 May 2022 17:01:19 +0200 Message-ID: <87bkwe3bk0.fsf@redhat.com> MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Vitaly Kuznetsov writes: > Changes since v1: This should've beed 'since v2', obviously. ... > > Currently, KVM handles HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST{,EX} requests > by flushing the whole VPID and this is sub-optimal. This series introduces > the required mechanism to make handling of these requests more > fine-grained by flushing individual GVAs only (when requested). On this > foundation, "Direct Virtual Flush" Hyper-V feature is implemented. The > feature allows L0 to handle Hyper-V TLB flush hypercalls directly at > L0 without the need to reflect the exit to L1. This has at least two > benefits: reflecting vmexit and the consequent vmenter are avoided + L0 > has precise information whether the target vCPU is actually running (and > thus requires a kick). FWIW, patches still apply cleanly to kvm/queue so probably there's no need to resend. -- Vitaly