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 17BD1C433F5 for ; Wed, 5 Jan 2022 10:10:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239249AbiAEKKF (ORCPT ); Wed, 5 Jan 2022 05:10:05 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]:52115 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239230AbiAEKKD (ORCPT ); Wed, 5 Jan 2022 05:10:03 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1641377402; 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=EYIR7J8q3TIsA84CjFhzw4cuwyQF/1ednNVnYGVZmik=; b=TRaxEw6jixPKdtJdxBDXtv+oHGee18f2BMho8y1tOJrN0sOX/5AlUzZSK6svp0xvc6E9+4 5VxEKtxzoZ28CIsFNgMw7e6tn3R+2fu+kkte3jY1DUfqif22/DqFFM6oZ1lwgEFKCdOEdX MQ1I7B4B4+s2PmMWe8D5r69WPTIyQK8= Received: from mail-wm1-f72.google.com (mail-wm1-f72.google.com [209.85.128.72]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-581-d7osVy-ANqaEG-D3u-m7tQ-1; Wed, 05 Jan 2022 05:10:01 -0500 X-MC-Unique: d7osVy-ANqaEG-D3u-m7tQ-1 Received: by mail-wm1-f72.google.com with SMTP id az9-20020a05600c600900b0034692565ca8so420604wmb.9 for ; Wed, 05 Jan 2022 02:10:00 -0800 (PST) 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=EYIR7J8q3TIsA84CjFhzw4cuwyQF/1ednNVnYGVZmik=; b=AaIePMDaL05h1uL5DqaAO7MFB5f9dUB9jLHlQlZGliu63cUIAyBq09l3+ZWQatZPiW nxbrBOxC22wzH1eTvBnIvWY0tvEdcfi86EtDRAJK3i5WD6U+GcyWnCUQk1iPXwsAQcpz npNxtjNbnMwdpbPT3pXvqCagQlSTAEtjnvz1EwoMZ1hGyYAZ0467f64XYyrxi/YE1qZa 4xwBGEV7+U6xFpMF14U4IVMzDno+sFXYMrWQikFGqgdaCrQDkSI4aRqOjE8wEyNRSQOt YIzG+7l3bFhHkkhBRoUAW0RrKApva+S7ApJTVmVCQc+HiJLR3O5N0RIccbjtTevEZNru bVYA== X-Gm-Message-State: AOAM531o6exH+D/FDNAYQcR6uGgvz59Rn5OXUQ7tvW6MJP5LX/oYJWcn 01pPUDyDz+NqAl877YAIVFFLPH8xhv7m1wqmfDaXSdQk8yAGCcs96xtrX9YsVHgieLSzhaI1JSF Zmmx/ZpI+CYxzqDT8DhhzeBxAQ3ScpNuZvPuu1zAYgkd/5oLeHWLEc2gQPa9MS7OkRGWMdMr1nc OF X-Received: by 2002:adf:e88a:: with SMTP id d10mr45695175wrm.114.1641377400050; Wed, 05 Jan 2022 02:10:00 -0800 (PST) X-Google-Smtp-Source: ABdhPJzoVBTcoWqt1ECD+LSMEnDyPI0xZ67s0U9dh842SryfHZy6fU5K7FRHxyT9LDZAuN/0IuqVnA== X-Received: by 2002:adf:e88a:: with SMTP id d10mr45695160wrm.114.1641377399867; Wed, 05 Jan 2022 02:09:59 -0800 (PST) Received: from fedora (nat-2.ign.cz. [91.219.240.2]) by smtp.gmail.com with ESMTPSA id q3sm4505633wrr.55.2022.01.05.02.09.59 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 05 Jan 2022 02:09:59 -0800 (PST) From: Vitaly Kuznetsov To: Paolo Bonzini , Igor Mammedov Cc: kvm@vger.kernel.org, Sean Christopherson , Wanpeng Li , Jim Mattson , linux-kernel@vger.kernel.org Subject: Re: [PATCH 2/2] KVM: x86: Forbid KVM_SET_CPUID{,2} after KVM_RUN In-Reply-To: References: <20211122175818.608220-1-vkuznets@redhat.com> <20211122175818.608220-3-vkuznets@redhat.com> <16368a89-99ea-e52c-47b6-bd006933ec1f@redhat.com> <20211227183253.45a03ca2@redhat.com> <61325b2b-dc93-5db2-2d0a-dd0900d947f2@redhat.com> <87mtkdqm7m.fsf@redhat.com> <20220103104057.4dcf7948@redhat.com> <875yr1q8oa.fsf@redhat.com> Date: Wed, 05 Jan 2022 11:09:58 +0100 Message-ID: <87o84qpk7d.fsf@redhat.com> MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Paolo Bonzini writes: > On 1/3/22 13:56, Vitaly Kuznetsov wrote: >> 'allowlist' of things which can change (and put >> *APICids there) and only fail KVM_SET_CPUID{,2} when we see something >> else changing. > > We could also go the other way and only deny changes that result in > changed CPU caps. That should be easier to implement since we have > already a mapping from CPU capability words to CPUID leaves and registers. > Good idea, I'll look into it (if noone beats me to it). -- Vitaly