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=-6.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 93855C433EF for ; Thu, 9 Sep 2021 07:03:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 760DC60F92 for ; Thu, 9 Sep 2021 07:03:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235970AbhIIHEi (ORCPT ); Thu, 9 Sep 2021 03:04:38 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:27984 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1349701AbhIIHEX (ORCPT ); Thu, 9 Sep 2021 03:04:23 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1631170994; 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=HUBvw8j4TFsIarEE3fvS4je6Jlh+kiHU2Hz8uuU8quY=; b=OMHBICrXOX3Wd5IKXUVlPp9xsXdieMxv9xiTrqDnKWdJQ6yo69nG61tE+NGOUzgzHTAHXt PktDFLZ0DXX9AZT9YRETBnwSdF0ssgYt1fQEZWJIv91vWBrHUpctqbbjOrW47hKkiVq1BH NH7OU8yDPOOeETnOisouxY0WncUq+Y4= Received: from mail-wm1-f71.google.com (mail-wm1-f71.google.com [209.85.128.71]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-439-rq9zq7qsM---_pI0Kw8_xQ-1; Thu, 09 Sep 2021 03:03:13 -0400 X-MC-Unique: rq9zq7qsM---_pI0Kw8_xQ-1 Received: by mail-wm1-f71.google.com with SMTP id c2-20020a7bc8420000b0290238db573ab7so462134wml.5 for ; Thu, 09 Sep 2021 00:03:12 -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=HUBvw8j4TFsIarEE3fvS4je6Jlh+kiHU2Hz8uuU8quY=; b=PqA0xFDVfiqSRQhW1GTLp0nnp6fqIDVFRn8fLLjh4s9Bep4O6aKX5xJMXUiyWVG/sP enfubnwbu2kT2CbZWvfEeNgSDsfO4uxs6ZK0kD46hyI5lhC7nb387pUKtE545j8OhE+v pFwMCCTwZucGubWBGADUHUm1y3z2PlWnIcvYvoL1zoydsFVBIHBJDIw3rD+F3aMQge0K nUtyPQa/l0AUnM4nxrQFMaT2vU0ZRb6cEtLHNL8o4PeLPGHT5XqWxmaNeJBgwf8CPGyJ /3KIdHlYYBVAIX+PLVBHD9xDLNqh/LMRJdtzcuiNO1fC9O29gLWLrkQRcWEW+2fxBHFp SQHw== X-Gm-Message-State: AOAM5314Vd6bUm0C//Cet4Uv3qSC4fwvQ+2hPTO9qLQt/AVHr+5crALJ K1WrqT9DeFrW1O50FmdyK3/8NRnd45lgJHKbu2skTnxGz8HURDs23hHo2fBUJvKFJj+o5KVSYBX uCWU2GVwucHEauPa0tyrLJj+mOyhywEJZpgdZ0LIBn+XiPOZ1/DjryOqRj555qabinEugRmzucx En X-Received: by 2002:a7b:c5d8:: with SMTP id n24mr1273454wmk.51.1631170992002; Thu, 09 Sep 2021 00:03:12 -0700 (PDT) X-Google-Smtp-Source: ABdhPJw5z30hb9JghYpVAxn6JQxbFF6EQTeK8au3fTsIagXnuaKAVmndHuei2cK1lD1nFMAodiZ0bg== X-Received: by 2002:a7b:c5d8:: with SMTP id n24mr1273436wmk.51.1631170991804; Thu, 09 Sep 2021 00:03:11 -0700 (PDT) Received: from vitty.brq.redhat.com (g-server-2.ign.cz. [91.219.240.2]) by smtp.gmail.com with ESMTPSA id l1sm266046wmq.8.2021.09.09.00.03.10 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 09 Sep 2021 00:03:11 -0700 (PDT) From: Vitaly Kuznetsov To: Sean Christopherson Cc: kvm@vger.kernel.org, Paolo Bonzini , Wanpeng Li , Jim Mattson , linux-kernel@vger.kernel.org Subject: Re: [PATCH] KVM: nVMX: Filter out all unsupported controls when eVMCS was activated In-Reply-To: References: <20210907163530.110066-1-vkuznets@redhat.com> Date: Thu, 09 Sep 2021 09:03:10 +0200 Message-ID: <87v93a2pu9.fsf@vitty.brq.redhat.com> MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Sean Christopherson writes: > On Tue, Sep 07, 2021, Vitaly Kuznetsov wrote: >> Let's be bold this time and instead of playing whack-a-mole just filter out >> all unsupported controls from VMX MSRs. > > Out of curiosity, why didn't we do this from the get-go? We actually did, the initial implementation (57b119da3594f) was filtering out everything but then things changed in "only clear controls which are known to cause issues" (31de3d2500e4). I forgot everything already but was able to google this suggestion from Paolo: https://www.lkml.org/lkml/2020/1/22/1108 so finally we've settled on a shortened list. Now as new Windows version is out, we have new problems to solve) -- Vitaly