From patchwork Fri Aug 6 07:42:17 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Yang, Weijiang" X-Patchwork-Id: 12422813 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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 AAC77C4338F for ; Fri, 6 Aug 2021 07:29:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 942C2611CC for ; Fri, 6 Aug 2021 07:29:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243765AbhHFHaA (ORCPT ); Fri, 6 Aug 2021 03:30:00 -0400 Received: from mga05.intel.com ([192.55.52.43]:16368 "EHLO mga05.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243720AbhHFH3t (ORCPT ); Fri, 6 Aug 2021 03:29:49 -0400 X-IronPort-AV: E=McAfee;i="6200,9189,10067"; a="299913778" X-IronPort-AV: E=Sophos;i="5.84,299,1620716400"; d="scan'208";a="299913778" Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga105.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 06 Aug 2021 00:29:33 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.84,299,1620716400"; d="scan'208";a="513102418" Received: from michael-optiplex-9020.sh.intel.com ([10.239.159.182]) by FMSMGA003.fm.intel.com with ESMTP; 06 Aug 2021 00:29:31 -0700 From: Yang Weijiang To: pbonzini@redhat.com, jmattson@google.com, seanjc@google.com, vkuznets@redhat.com, wei.w.wang@intel.com, like.xu.linux@gmail.com, kvm@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Yang Weijiang Subject: [PATCH v7 07/15] KVM: x86: Refresh CPUID on writes to MSR_IA32_XSS Date: Fri, 6 Aug 2021 15:42:17 +0800 Message-Id: <1628235745-26566-8-git-send-email-weijiang.yang@intel.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1628235745-26566-1-git-send-email-weijiang.yang@intel.com> References: <1628235745-26566-1-git-send-email-weijiang.yang@intel.com> Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Updated CPUID.0xD.0x1, which reports the current required storage size of all features enabled via XCR0 | XSS, when the guest's XSS is modified. Note, KVM does not yet support any XSS based features, i.e. supported_xss is guaranteed to be zero at this time. Co-developed-by: Zhang Yi Z Signed-off-by: Zhang Yi Z Signed-off-by: Yang Weijiang Message-Id: <20210203113421.5759-3-weijiang.yang@intel.com> Signed-off-by: Paolo Bonzini --- arch/x86/include/asm/kvm_host.h | 1 + arch/x86/kvm/cpuid.c | 21 ++++++++++++++++++--- arch/x86/kvm/x86.c | 7 +++++-- 3 files changed, 24 insertions(+), 5 deletions(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 974cbfb1eefe..4a4fb99e8a99 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -692,6 +692,7 @@ struct kvm_vcpu_arch { u64 xcr0; u64 guest_supported_xcr0; + u64 guest_supported_xss; struct kvm_pio_request pio; void *pio_data; diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index 739be5da3bca..03025eea1524 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -131,9 +131,24 @@ void kvm_update_cpuid_runtime(struct kvm_vcpu *vcpu) best->ebx = xstate_required_size(vcpu->arch.xcr0, false); best = kvm_find_cpuid_entry(vcpu, 0xD, 1); - if (best && (cpuid_entry_has(best, X86_FEATURE_XSAVES) || - cpuid_entry_has(best, X86_FEATURE_XSAVEC))) - best->ebx = xstate_required_size(vcpu->arch.xcr0, true); + if (best) { + if (cpuid_entry_has(best, X86_FEATURE_XSAVES) || + cpuid_entry_has(best, X86_FEATURE_XSAVEC)) { + u64 xstate = vcpu->arch.xcr0 | vcpu->arch.ia32_xss; + + best->ebx = xstate_required_size(xstate, true); + } + + if (!cpuid_entry_has(best, X86_FEATURE_XSAVES)) { + best->ecx = 0; + best->edx = 0; + } + vcpu->arch.guest_supported_xss = + (((u64)best->edx << 32) | best->ecx) & supported_xss; + + } else { + vcpu->arch.guest_supported_xss = 0; + } best = kvm_find_cpuid_entry(vcpu, KVM_CPUID_FEATURES, 0); if (kvm_hlt_in_guest(vcpu->kvm) && best && diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 4ae173ab2208..08a58ef8bec2 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -3358,9 +3358,12 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info) * IA32_XSS[bit 8]. Guests have to use RDMSR/WRMSR rather than * XSAVES/XRSTORS to save/restore PT MSRs. */ - if (data & ~supported_xss) + if (data & ~vcpu->arch.guest_supported_xss) return 1; - vcpu->arch.ia32_xss = data; + if (vcpu->arch.ia32_xss != data) { + vcpu->arch.ia32_xss = data; + kvm_update_cpuid_runtime(vcpu); + } break; case MSR_SMI_COUNT: if (!msr_info->host_initiated)