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 520E4C00528 for ; Fri, 4 Aug 2023 21:44:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229633AbjHDVoJ (ORCPT ); Fri, 4 Aug 2023 17:44:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53420 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229638AbjHDVoG (ORCPT ); Fri, 4 Aug 2023 17:44:06 -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 ESMTPS id 77683F7 for ; Fri, 4 Aug 2023 14:43:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1691185400; 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: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=WRmxLYIrCgq02IXbbQhHjflMDPccTOFGrJky+eGE/k8=; b=Kz2HubX5PRxVoxh5u5QQfLfAbWez7Rlioe70pGpvUypui8JPSEfO+KAIw3DOIUwYj9A9NO uJ6Z3500X26RVWEuM7BAUc9J/YpD3M5VmKtgMlB1LuP/8wxc11GCAKeGugKTvAsCRRYLTk yK/fPRqC7Ne39dkwVl0SIVVSf8C0yvY= Received: from mail-ej1-f72.google.com (mail-ej1-f72.google.com [209.85.218.72]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-150-4cQ1ftqCPsyUSAVWywxP8Q-1; Fri, 04 Aug 2023 17:43:19 -0400 X-MC-Unique: 4cQ1ftqCPsyUSAVWywxP8Q-1 Received: by mail-ej1-f72.google.com with SMTP id a640c23a62f3a-99cb1b83eacso100093566b.1 for ; Fri, 04 Aug 2023 14:43:19 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1691185398; x=1691790198; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=WRmxLYIrCgq02IXbbQhHjflMDPccTOFGrJky+eGE/k8=; b=glKO+Dj0XxjHn/GW2vyRoBaBK/FbT2oe02L2bwsxt0iHWhY9teBziI2ZYbC+Fwc0vP Nk5XN/OUFRN15MkBgpwDnA3FoEbfI9uRJWuLQvY3Fuy5wftl7fbXrTOVFMfeUb9LJWuo IAt8BpbGi3V0wZyaupr8TmiQP9oWQR4BhqGlmtLJlIv7EiJk6pkQNpl3XcQHT9y6+5jj XVj2Bt1bwaZTJ2yAFSWR26Jput3dohiC+lkj2hGnBEly+O7KWw1cSszxkAQAD4yYTN2K 6d8FZwLUBIoZpv2FzCS+PJKz43FlABQiIarlLiWggQgeYgWGGafOcreTRIX2p0jf/byt JG+w== X-Gm-Message-State: AOJu0Yzfhg8wBT1Shq6FwImTikGEz0F65snInN50n0pur4UjlKwNnfRJ GFV7cY6J66ZHN1D1ghCx7YX0o0jDlpYF647ZbNYT9fsPjBFC6JKo4l6MrK8OkXq+lVDTjvU+zJP E1SuyTAspJ/NlYy1ZC3/64zEe X-Received: by 2002:a17:906:8a44:b0:99b:cdfd:fb44 with SMTP id gx4-20020a1709068a4400b0099bcdfdfb44mr913701ejc.9.1691185398326; Fri, 04 Aug 2023 14:43:18 -0700 (PDT) X-Google-Smtp-Source: AGHT+IEklM3VILACDcACrvQk+qwlMw4FzbNi8o+s75zI78aYnVIs33rmzbnT6NaghC2ulWxNTYj5zA== X-Received: by 2002:a17:906:8a44:b0:99b:cdfd:fb44 with SMTP id gx4-20020a1709068a4400b0099bcdfdfb44mr913686ejc.9.1691185397983; Fri, 04 Aug 2023 14:43:17 -0700 (PDT) Received: from ?IPV6:2001:b07:6468:f312:63a7:c72e:ea0e:6045? ([2001:b07:6468:f312:63a7:c72e:ea0e:6045]) by smtp.googlemail.com with ESMTPSA id x14-20020a1709064bce00b0098f33157e7dsm1826649ejv.82.2023.08.04.14.43.16 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 04 Aug 2023 14:43:17 -0700 (PDT) Message-ID: <8066f19d-68e9-711b-acdb-7554475602e6@redhat.com> Date: Fri, 4 Aug 2023 23:43:15 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.13.0 Subject: Re: [PATCH v5 04/19] KVM:x86: Refresh CPUID on write to guest MSR_IA32_XSS Content-Language: en-US To: Sean Christopherson , Yang Weijiang Cc: peterz@infradead.org, john.allen@amd.com, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, rick.p.edgecombe@intel.com, chao.gao@intel.com, binbin.wu@linux.intel.com, Zhang Yi Z References: <20230803042732.88515-1-weijiang.yang@intel.com> <20230803042732.88515-5-weijiang.yang@intel.com> From: Paolo Bonzini In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 8/4/23 18:02, Sean Christopherson wrote: >> Update CPUID(EAX=0DH,ECX=1) when the guest's XSS is modified. >> CPUID(EAX=0DH,ECX=1).EBX reports required storage size of >> all enabled xstate features in XCR0 | XSS. Guest can allocate >> sufficient xsave buffer based on the info. > > Please wrap changelogs closer to ~75 chars. I'm pretty sure this isn't the first > time I've made this request... I suspect this is because of the long "word" CPUID(EAX=0DH,ECX=1).EBX. It would make the lengths less homogeneous if lines 1 stayed the same but lines 2-4 became longer. Paolo