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 375E0C04E69 for ; Fri, 4 Aug 2023 22:03:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230265AbjHDWD0 (ORCPT ); Fri, 4 Aug 2023 18:03:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58928 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229887AbjHDWDX (ORCPT ); Fri, 4 Aug 2023 18:03:23 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3FCC110E6 for ; Fri, 4 Aug 2023 15:02:37 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1691186556; 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=7XeJdVl8/EwMUOdjx3edZoXx1Zn1CMa9oW0ZCIdFrDM=; b=TeoY2YZpBF7YdrwFMyO1Zq6G86TeWDEUNNKiTdLibhBGb4nj0IJdm5P8Qy8wuRjNnJwtJz F50bHrMTZE6mVvu6g+6T8Ej87aifH3OWXLvDUIynuX66M/3H/nlQdEeYq6ClSm/L0g8wEp 2UHKFVgG40wxqe0E+VxV6h2+NTCYCAo= Received: from mail-ed1-f69.google.com (mail-ed1-f69.google.com [209.85.208.69]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-617-UweH5cW7PIWwMjd0sOoEAA-1; Fri, 04 Aug 2023 18:02:34 -0400 X-MC-Unique: UweH5cW7PIWwMjd0sOoEAA-1 Received: by mail-ed1-f69.google.com with SMTP id 4fb4d7f45d1cf-5223854ef71so1660046a12.1 for ; Fri, 04 Aug 2023 15:02:34 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1691186554; x=1691791354; 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=7XeJdVl8/EwMUOdjx3edZoXx1Zn1CMa9oW0ZCIdFrDM=; b=Pwfn/YE612iNdnm7KBDnrhj0SueZUkUs9O3F3vRA+cDZEHRzp6xNPMx0qtw8SRa40x H33JysIr7RC8m2otscq0SI+23IRVaZa1vilcWPZRTLF1Z7roM54vyYVMBdJM24tkb6Kt yIIy0b75wv1sUXp9YHjgXGW8yx1u5QJHRNLpkC2Snt3Fz34VTuNTBn73D7BITh8E4QxC dfOPLlJtbk2p7qsmyLQutMnmzVYzgR3v+voCQffWCmNXNievxOWfqaE5bGn79IXLRP26 HnhsXXUnkK7fG8ZvXY4hSrL5HToAEXQuEFYiurnBjygVA0fO4YyEGtutBaF8HGcTG2+N HbKQ== X-Gm-Message-State: AOJu0YwwaLcChJKCGYjKub87UFjr2bbpWFuVll+op9oFWgtXXzEsd2a+ UE8/2+1dwoRXAA9f02KmRNl6q+LthOQST9Tmot6435bX9a5omwi+17V/iTyyKe3Cz8ci606o6qO rVmHAc5NOdzqdv9vSgDyP2qUz X-Received: by 2002:aa7:c6cb:0:b0:51e:309:2e11 with SMTP id b11-20020aa7c6cb000000b0051e03092e11mr2389835eds.36.1691186553785; Fri, 04 Aug 2023 15:02:33 -0700 (PDT) X-Google-Smtp-Source: AGHT+IE0tj1V215ZmqouMVSJ2M+alZff9GBiz+Yk8qF5u4t9uMgWOORSyfJG5ZAuBVk+SWA9STrj2A== X-Received: by 2002:aa7:c6cb:0:b0:51e:309:2e11 with SMTP id b11-20020aa7c6cb000000b0051e03092e11mr2389825eds.36.1691186553557; Fri, 04 Aug 2023 15:02:33 -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 e26-20020a50ec9a000000b0051873c201a0sm1780958edr.26.2023.08.04.15.02.32 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 04 Aug 2023 15:02:32 -0700 (PDT) Message-ID: <3075190f-d8a5-0d7d-56e9-671a2052d20f@redhat.com> Date: Sat, 5 Aug 2023 00:02:28 +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 17/19] KVM:x86: Enable guest CET supervisor xstate bit support Content-Language: en-US To: Yang Weijiang , seanjc@google.com, peterz@infradead.org, john.allen@amd.com, kvm@vger.kernel.org, linux-kernel@vger.kernel.org Cc: rick.p.edgecombe@intel.com, chao.gao@intel.com, binbin.wu@linux.intel.com References: <20230803042732.88515-1-weijiang.yang@intel.com> <20230803042732.88515-18-weijiang.yang@intel.com> From: Paolo Bonzini In-Reply-To: <20230803042732.88515-18-weijiang.yang@intel.com> 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 8/3/23 06:27, Yang Weijiang wrote: > if (boot_cpu_has(X86_FEATURE_XSAVES)) { > + u32 eax, ebx, ecx, edx; > + > + cpuid_count(0xd, 1, &eax, &ebx, &ecx, &edx); > rdmsrl(MSR_IA32_XSS, host_xss); > kvm_caps.supported_xss = host_xss & KVM_SUPPORTED_XSS; > + if (ecx & XFEATURE_MASK_CET_KERNEL) > + kvm_caps.supported_xss |= XFEATURE_MASK_CET_KERNEL; > } This is a bit hackish and makes me lean more towards adding support for XFEATURE_MASK_CET_KERNEL in host MSR_IA32_XSS (and then possibly hide it in the actual calls to XSAVE/XRSTORS for non-guest FPU). Paolo