From patchwork Thu Dec 21 14:02:21 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Yang, Weijiang" X-Patchwork-Id: 13501440 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.24]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A918F4E1D0; Thu, 21 Dec 2023 09:03:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="Q/RqZ4sd" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1703149430; x=1734685430; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=80A9OCb5g70NX77dvI1N49bHlokeM5y3fENbkVjwY90=; b=Q/RqZ4sdjzCVUPB5rZDSHECI4rY5M4j9NxHdqiv5MZU+ebfdkUL67O3P mUfDT/0kzBxggI5pEe93vR1uOY1T3JSDX9V44q1IoqwpWjRHKe4IC5iCU k4y2rtGQxagK25RkQhTswXpWKOQX2Ue7t19KOrMhZoRRonT7dDP+uvjVY cTTKY+TcRXKvsnJuutZCC8aKPa44l7IohbpOyzVcsEF+lRP4jYRDkxGnA 6DCZzVAvQ8dABhCbLsJHkZtq92u6BA6AAWGRGS6AHjYB061dhlnkvzVNO XMWvKZr1KQzZKqXLw2KvzPFvAzbkGk0wRhQkAFTfB57S+6RfVgPUOj5RC w==; X-IronPort-AV: E=McAfee;i="6600,9927,10930"; a="398729648" X-IronPort-AV: E=Sophos;i="6.04,293,1695711600"; d="scan'208";a="398729648" Received: from orsmga004.jf.intel.com ([10.7.209.38]) by orsmga102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 21 Dec 2023 01:03:44 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10930"; a="900028584" X-IronPort-AV: E=Sophos;i="6.04,293,1695711600"; d="scan'208";a="900028584" Received: from 984fee00a5ca.jf.intel.com (HELO embargo.jf.intel.com) ([10.165.9.183]) by orsmga004-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 21 Dec 2023 01:03:10 -0800 From: Yang Weijiang To: seanjc@google.com, pbonzini@redhat.com, dave.hansen@intel.com, kvm@vger.kernel.org, linux-kernel@vger.kernel.org Cc: peterz@infradead.org, chao.gao@intel.com, rick.p.edgecombe@intel.com, mlevitsk@redhat.com, john.allen@amd.com, weijiang.yang@intel.com Subject: [PATCH v8 08/26] KVM: x86: Rework cpuid_get_supported_xcr0() to operate on vCPU data Date: Thu, 21 Dec 2023 09:02:21 -0500 Message-Id: <20231221140239.4349-9-weijiang.yang@intel.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20231221140239.4349-1-weijiang.yang@intel.com> References: <20231221140239.4349-1-weijiang.yang@intel.com> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Sean Christopherson Rework and rename cpuid_get_supported_xcr0() to explicitly operate on vCPU state, i.e. on a vCPU's CPUID state, now that the only usage of the helper is to retrieve a vCPU's already-set CPUID. Prior to commit 275a87244ec8 ("KVM: x86: Don't adjust guest's CPUID.0x12.1 (allowed SGX enclave XFRM)"), KVM incorrectly fudged guest CPUID at runtime, which in turn necessitated massaging the incoming CPUID state for KVM_SET_CPUID{2} so as not to run afoul of kvm_cpuid_check_equal(). I.e. KVM also invoked cpuid_get_supported_xcr0() with the incoming CPUID state, and thus without an explicit vCPU object. Opportunistically move the helper below kvm_update_cpuid_runtime() to make it harder to repeat the mistake of querying supported XCR0 for runtime updates. No functional change intended. Signed-off-by: Sean Christopherson Signed-off-by: Yang Weijiang Reviewed-by: Maxim Levitsky --- arch/x86/kvm/cpuid.c | 33 ++++++++++++++++----------------- 1 file changed, 16 insertions(+), 17 deletions(-) diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index 294e5bd5f8a0..624954203b40 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -247,21 +247,6 @@ void kvm_update_pv_runtime(struct kvm_vcpu *vcpu) vcpu->arch.pv_cpuid.features = best->eax; } -/* - * Calculate guest's supported XCR0 taking into account guest CPUID data and - * KVM's supported XCR0 (comprised of host's XCR0 and KVM_SUPPORTED_XCR0). - */ -static u64 cpuid_get_supported_xcr0(struct kvm_cpuid_entry2 *entries, int nent) -{ - struct kvm_cpuid_entry2 *best; - - best = cpuid_entry2_find(entries, nent, 0xd, 0); - if (!best) - return 0; - - return (best->eax | ((u64)best->edx << 32)) & kvm_caps.supported_xcr0; -} - static void __kvm_update_cpuid_runtime(struct kvm_vcpu *vcpu, struct kvm_cpuid_entry2 *entries, int nent) { @@ -312,6 +297,21 @@ void kvm_update_cpuid_runtime(struct kvm_vcpu *vcpu) } EXPORT_SYMBOL_GPL(kvm_update_cpuid_runtime); +/* + * Calculate guest's supported XCR0 taking into account guest CPUID data and + * KVM's supported XCR0 (comprised of host's XCR0 and KVM_SUPPORTED_XCR0). + */ +static u64 vcpu_get_supported_xcr0(struct kvm_vcpu *vcpu) +{ + struct kvm_cpuid_entry2 *best; + + best = kvm_find_cpuid_entry_index(vcpu, 0xd, 0); + if (!best) + return 0; + + return (best->eax | ((u64)best->edx << 32)) & kvm_caps.supported_xcr0; +} + static bool kvm_cpuid_has_hyperv(struct kvm_cpuid_entry2 *entries, int nent) { #ifdef CONFIG_KVM_HYPERV @@ -361,8 +361,7 @@ static void kvm_vcpu_after_set_cpuid(struct kvm_vcpu *vcpu) kvm_apic_set_version(vcpu); } - vcpu->arch.guest_supported_xcr0 = - cpuid_get_supported_xcr0(vcpu->arch.cpuid_entries, vcpu->arch.cpuid_nent); + vcpu->arch.guest_supported_xcr0 = vcpu_get_supported_xcr0(vcpu); kvm_update_pv_runtime(vcpu);