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 96784EDE99C for ; Thu, 14 Sep 2023 09:39:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237505AbjINJjS (ORCPT ); Thu, 14 Sep 2023 05:39:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49848 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237398AbjINJi2 (ORCPT ); Thu, 14 Sep 2023 05:38:28 -0400 Received: from mgamail.intel.com (mgamail.intel.com [192.55.52.88]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C14EE1FCA; Thu, 14 Sep 2023 02:38:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1694684301; x=1726220301; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=VPJQf4U39E7DZwum/HGUJ0vCeET4v76K5tsmsMkVRMg=; b=lGwzX0Qb5ZuZQ70Fj6+m3l6vg6oZMquG+OQbxq5MMbRRGUzekiD1FVOU OGrUVh4BflXRTYbhMmYw/dNZQVf2VjBboDzpJoAPxrKXBqTSyxK/o1wIU FCd1J+wNKsxPxSRqmewM+Bykz/66eXoTjZk/sluMQyWbCVI0JzAdsyWnB ZLDy5SJa2MShWJii4+u+DbhT+C6RR9JxnnYzyceaigz1jPH81Qnk5o5w5 LiJ5/sauFu7PspVGFFlyh4KP4mM6G87N8j5nao87OfonYy1GfpJDfRo4q HC4TiHs1cfaEUlbVXmiBR8I6pYuL0uFgrQEAUNiNnnIUuXKYPWRqVfQ7Y w==; X-IronPort-AV: E=McAfee;i="6600,9927,10832"; a="409857396" X-IronPort-AV: E=Sophos;i="6.02,145,1688454000"; d="scan'208";a="409857396" Received: from fmsmga007.fm.intel.com ([10.253.24.52]) by fmsmga101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Sep 2023 02:38:21 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10832"; a="747656270" X-IronPort-AV: E=Sophos;i="6.02,145,1688454000"; d="scan'208";a="747656270" Received: from embargo.jf.intel.com ([10.165.9.183]) by fmsmga007-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Sep 2023 02:38:21 -0700 From: Yang Weijiang To: seanjc@google.com, pbonzini@redhat.com, kvm@vger.kernel.org, linux-kernel@vger.kernel.org Cc: dave.hansen@intel.com, peterz@infradead.org, chao.gao@intel.com, rick.p.edgecombe@intel.com, weijiang.yang@intel.com, john.allen@amd.com Subject: [PATCH v6 16/25] KVM: x86: Report KVM supported CET MSRs as to-be-saved Date: Thu, 14 Sep 2023 02:33:16 -0400 Message-Id: <20230914063325.85503-17-weijiang.yang@intel.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20230914063325.85503-1-weijiang.yang@intel.com> References: <20230914063325.85503-1-weijiang.yang@intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Add CET MSRs to the list of MSRs reported to userspace if the feature, i.e. IBT or SHSTK, associated with the MSRs is supported by KVM. SSP can only be read via RDSSP. Writing even requires destructive and potentially faulting operations such as SAVEPREVSSP/RSTORSSP or SETSSBSY/CLRSSBSY. Let the host use a pseudo-MSR that is just a wrapper for the GUEST_SSP field of the VMCS. Suggested-by: Chao Gao Signed-off-by: Yang Weijiang --- arch/x86/include/uapi/asm/kvm_para.h | 1 + arch/x86/kvm/vmx/vmx.c | 2 ++ arch/x86/kvm/x86.c | 18 ++++++++++++++++++ 3 files changed, 21 insertions(+) diff --git a/arch/x86/include/uapi/asm/kvm_para.h b/arch/x86/include/uapi/asm/kvm_para.h index 6e64b27b2c1e..9864bbcf2470 100644 --- a/arch/x86/include/uapi/asm/kvm_para.h +++ b/arch/x86/include/uapi/asm/kvm_para.h @@ -58,6 +58,7 @@ #define MSR_KVM_ASYNC_PF_INT 0x4b564d06 #define MSR_KVM_ASYNC_PF_ACK 0x4b564d07 #define MSR_KVM_MIGRATION_CONTROL 0x4b564d08 +#define MSR_KVM_SSP 0x4b564d09 struct kvm_steal_time { __u64 steal; diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index 72e3943f3693..9409753f45b0 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -7009,6 +7009,8 @@ static bool vmx_has_emulated_msr(struct kvm *kvm, u32 index) case MSR_AMD64_TSC_RATIO: /* This is AMD only. */ return false; + case MSR_KVM_SSP: + return kvm_cpu_cap_has(X86_FEATURE_SHSTK); default: return true; } diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index dda9c7141ea1..73b45351c0fc 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -1476,6 +1476,9 @@ static const u32 msrs_to_save_base[] = { MSR_IA32_XFD, MSR_IA32_XFD_ERR, MSR_IA32_XSS, + MSR_IA32_U_CET, MSR_IA32_S_CET, + MSR_IA32_PL0_SSP, MSR_IA32_PL1_SSP, MSR_IA32_PL2_SSP, + MSR_IA32_PL3_SSP, MSR_IA32_INT_SSP_TAB, }; static const u32 msrs_to_save_pmu[] = { @@ -1576,6 +1579,7 @@ static const u32 emulated_msrs_all[] = { MSR_K7_HWCR, MSR_KVM_POLL_CONTROL, + MSR_KVM_SSP, }; static u32 emulated_msrs[ARRAY_SIZE(emulated_msrs_all)]; @@ -7241,6 +7245,20 @@ static void kvm_probe_msr_to_save(u32 msr_index) if (!kvm_caps.supported_xss) return; break; + case MSR_IA32_U_CET: + case MSR_IA32_S_CET: + if (!kvm_cpu_cap_has(X86_FEATURE_SHSTK) && + !kvm_cpu_cap_has(X86_FEATURE_IBT)) + return; + break; + case MSR_IA32_INT_SSP_TAB: + if (!kvm_cpu_cap_has(X86_FEATURE_LM)) + return; + fallthrough; + case MSR_IA32_PL0_SSP ... MSR_IA32_PL3_SSP: + if (!kvm_cpu_cap_has(X86_FEATURE_SHSTK)) + return; + break; default: break; } -- 2.27.0