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=-10.4 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,FSL_HELO_FAKE, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_IN_DEF_DKIM_WL 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 AA4DDC4338F for ; Fri, 6 Aug 2021 22:09:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 85D0D611EF for ; Fri, 6 Aug 2021 22:09:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S245471AbhHFWJ5 (ORCPT ); Fri, 6 Aug 2021 18:09:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49196 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239019AbhHFWJ4 (ORCPT ); Fri, 6 Aug 2021 18:09:56 -0400 Received: from mail-pj1-x102e.google.com (mail-pj1-x102e.google.com [IPv6:2607:f8b0:4864:20::102e]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0B1BEC061798 for ; Fri, 6 Aug 2021 15:09:40 -0700 (PDT) Received: by mail-pj1-x102e.google.com with SMTP id e2-20020a17090a4a02b029016f3020d867so19986899pjh.3 for ; Fri, 06 Aug 2021 15:09:40 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=yXtLp5mFbNs2K0XuuKSxUcF4dNWpNzn+5MPoGaJAJtU=; b=aSgDj0Y/r/a3naWQ65dmyylrY/CsJ6633DvELHg1r0k6vPieJelzG/b2jAcM3dDthJ wN8V8lFRUQH19JnK1STNdvVn92fIbgD3Uf+H613h2nNkFz6vWO6X660DRp1ypAU1EKWX v4k9UfqP641eCpZomgsyJ9w/L33qXNsr5WQAN5BX7BYOmzzyTN9nqBVkmUU69dl5dss9 3/3C4R6LtKQGcZxU9nApBIdgwB+LWSz4BlTlQKa+lIMmytzEYpTu5qlW2MRGkbfq/Sxr ioZr10k9Ogkzi+1Wv6dMdS0enZJAEVpIcI1FfS7QXw+XBwmQOYXJ0WfGZOUrFxcwRr2Y cK8Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=yXtLp5mFbNs2K0XuuKSxUcF4dNWpNzn+5MPoGaJAJtU=; b=CITs5j343q/TErI2PyTteDsF2buSYBzwqm+C7I95pLppEEZ1+Va1jc3X7qlEqI3lp+ kZSFyZm5A7ZXi8zWIkIzX+N4hLPw6yMgo6HNDmKGRTbhhIbDwqqLDkA7z1u8wJ2ttNrW ln5pNP6FDW2yldNr7feYSqOVsR+6jicUIWcvyZWpOzKnZRoUtnRFuawj74AO/58STacf 9ooudG8YQr/wSNJZDI/GGJ9AZ1Obl0xXb1pFhChQXiLgXWm+sOoXMA96svcsL81gbgoZ EMWXSXlW2RQiXRRQfumZW8x+Ox9fqnLLq5o+ExoCnrtDygnv5pgUZITPaNnScXU3dlGg iivg== X-Gm-Message-State: AOAM531/ooe/E9n6ULNcKpk68q7/77rO3DmC7n4+AcL9VRlcoKFZoqG8 VEXinpKKNP9De+4ckzLshIUmUQ== X-Google-Smtp-Source: ABdhPJyhhVa3xTLuiQI9QTy9DGbWO9kLU8eJ91KOYmDq8h019tDOaczTDzNrzWk9rEiBQKJeFV83AQ== X-Received: by 2002:a17:90b:4ac8:: with SMTP id mh8mr12080592pjb.5.1628287779379; Fri, 06 Aug 2021 15:09:39 -0700 (PDT) Received: from google.com (157.214.185.35.bc.googleusercontent.com. [35.185.214.157]) by smtp.gmail.com with ESMTPSA id qe3sm13080347pjb.21.2021.08.06.15.09.38 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 06 Aug 2021 15:09:38 -0700 (PDT) Date: Fri, 6 Aug 2021 22:09:35 +0000 From: Sean Christopherson To: Kai Huang Cc: isaku.yamahata@intel.com, Thomas Gleixner , Ingo Molnar , Borislav Petkov , "H . Peter Anvin" , Paolo Bonzini , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , erdemaktas@google.com, Connor Kuehl , x86@kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, isaku.yamahata@gmail.com, Rick Edgecombe Subject: Re: [RFC PATCH v2 41/69] KVM: x86: Add infrastructure for stolen GPA bits Message-ID: References: <20210805234424.d14386b79413845b990a18ac@intel.com> <20210806095922.6e2ca6587dc6f5b4fe8d52e7@intel.com> <20210807100006.3518bf9fbdecf13006030c22@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210807100006.3518bf9fbdecf13006030c22@intel.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Aug 07, 2021, Kai Huang wrote: > So could we have your final suggestion? :) Try the kvm_mmu_page_role.private approach. So long as it doesn't end up splattering code everywhere, I think that's more aligned with how KVM generally wants to treat the shared bit. In the changelog for this patch, make it very clear that ensuring different aliases get different shadow page (if necessary) is the responsiblity of each individual feature that leverages stolen gfn bits.