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 X-Spam-Level: X-Spam-Status: No, score=-9.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,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 76F81C2D0DB for ; Wed, 29 Jan 2020 23:48:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4B377206F0 for ; Wed, 29 Jan 2020 23:48:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727238AbgA2XsI (ORCPT ); Wed, 29 Jan 2020 18:48:08 -0500 Received: from mga06.intel.com ([134.134.136.31]:46688 "EHLO mga06.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727124AbgA2Xqr (ORCPT ); Wed, 29 Jan 2020 18:46:47 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga001.jf.intel.com ([10.7.209.18]) by orsmga104.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 29 Jan 2020 15:46:43 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.70,379,1574150400"; d="scan'208";a="309551719" Received: from sjchrist-coffee.jf.intel.com ([10.54.74.202]) by orsmga001.jf.intel.com with ESMTP; 29 Jan 2020 15:46:43 -0800 From: Sean Christopherson To: Paolo Bonzini Cc: Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , kvm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 09/26] KVM: x86: Calculate the supported xcr0 mask at load time Date: Wed, 29 Jan 2020 15:46:23 -0800 Message-Id: <20200129234640.8147-10-sean.j.christopherson@intel.com> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20200129234640.8147-1-sean.j.christopherson@intel.com> References: <20200129234640.8147-1-sean.j.christopherson@intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Add a new global variable, supported_xcr0, to track which xcr0 bits can be exposed to the guest instead of calculating the mask on every call. The supported bits are constant for a given instance of KVM. This paves the way toward eliminating the ->mpx_supported() call in kvm_mpx_supported(), e.g. eliminates multiple retpolines in VMX's nested VM-Enter path, and eventually toward eliminating ->mpx_supported() altogether. No functional change intended. Signed-off-by: Sean Christopherson --- arch/x86/kvm/cpuid.c | 15 ++------------- arch/x86/kvm/svm.c | 2 ++ arch/x86/kvm/vmx/vmx.c | 4 ++++ arch/x86/kvm/x86.c | 14 +++++++++++--- arch/x86/kvm/x86.h | 7 +------ 5 files changed, 20 insertions(+), 22 deletions(-) diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index b1c469446b07..51b604c9a3f5 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -52,16 +52,6 @@ bool kvm_mpx_supported(void) } EXPORT_SYMBOL_GPL(kvm_mpx_supported); -u64 kvm_supported_xcr0(void) -{ - u64 xcr0 = KVM_SUPPORTED_XCR0 & host_xcr0; - - if (!kvm_mpx_supported()) - xcr0 &= ~(XFEATURE_MASK_BNDREGS | XFEATURE_MASK_BNDCSR); - - return xcr0; -} - #define F feature_bit int kvm_update_cpuid(struct kvm_vcpu *vcpu) @@ -107,8 +97,7 @@ int kvm_update_cpuid(struct kvm_vcpu *vcpu) vcpu->arch.guest_xstate_size = XSAVE_HDR_SIZE + XSAVE_HDR_OFFSET; } else { vcpu->arch.guest_supported_xcr0 = - (best->eax | ((u64)best->edx << 32)) & - kvm_supported_xcr0(); + (best->eax | ((u64)best->edx << 32)) & supported_xcr0; vcpu->arch.guest_xstate_size = best->ebx = xstate_required_size(vcpu->arch.xcr0, false); } @@ -644,7 +633,7 @@ static inline int __do_cpuid_func(struct kvm_cpuid_entry2 *entry, u32 function, } case 0xd: { int idx, i; - u64 supported = kvm_supported_xcr0(); + u64 supported = supported_xcr0; entry->eax &= supported; entry->ebx = xstate_required_size(supported, false); diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index df4d0b6f31c8..f3e6dcefc094 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -1368,6 +1368,8 @@ static __init int svm_hardware_setup(void) init_msrpm_offsets(); + supported_xcr0 &= ~(XFEATURE_MASK_BNDREGS | XFEATURE_MASK_BNDCSR); + if (boot_cpu_has(X86_FEATURE_NX)) kvm_enable_efer_bits(EFER_NX); diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index ed63219ca52e..f16c1faf6ced 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -7620,6 +7620,10 @@ static __init int hardware_setup(void) WARN_ONCE(host_bndcfgs, "KVM: BNDCFGS in host will be lost"); } + if (!kvm_mpx_supported()) + supported_xcr0 &= ~(XFEATURE_MASK_BNDREGS | + XFEATURE_MASK_BNDCSR); + if (!cpu_has_vmx_vpid() || !cpu_has_vmx_invvpid() || !(cpu_has_vmx_invvpid_single() || cpu_has_vmx_invvpid_global())) enable_vpid = 0; diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index adbdbe785f05..03e656d05c15 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -180,6 +180,11 @@ struct kvm_shared_msrs { static struct kvm_shared_msrs_global __read_mostly shared_msrs_global; static struct kvm_shared_msrs __percpu *shared_msrs; +#define KVM_SUPPORTED_XCR0 (XFEATURE_MASK_FP | XFEATURE_MASK_SSE \ + | XFEATURE_MASK_YMM | XFEATURE_MASK_BNDREGS \ + | XFEATURE_MASK_BNDCSR | XFEATURE_MASK_AVX512 \ + | XFEATURE_MASK_PKRU) + static u64 __read_mostly host_xss; struct kvm_stats_debugfs_item debugfs_entries[] = { @@ -226,6 +231,8 @@ struct kvm_stats_debugfs_item debugfs_entries[] = { }; u64 __read_mostly host_xcr0; +u64 __read_mostly supported_xcr0; +EXPORT_SYMBOL_GPL(supported_xcr0); struct kmem_cache *x86_fpu_cache; EXPORT_SYMBOL_GPL(x86_fpu_cache); @@ -4081,8 +4088,7 @@ static int kvm_vcpu_ioctl_x86_set_xsave(struct kvm_vcpu *vcpu, * CPUID leaf 0xD, index 0, EDX:EAX. This is for compatibility * with old userspace. */ - if (xstate_bv & ~kvm_supported_xcr0() || - mxcsr & ~mxcsr_feature_mask) + if (xstate_bv & ~supported_xcr0 || mxcsr & ~mxcsr_feature_mask) return -EINVAL; load_xsave(vcpu, (u8 *)guest_xsave->region); } else { @@ -7310,8 +7316,10 @@ int kvm_arch_init(void *opaque) perf_register_guest_info_callbacks(&kvm_guest_cbs); - if (boot_cpu_has(X86_FEATURE_XSAVE)) + if (boot_cpu_has(X86_FEATURE_XSAVE)) { host_xcr0 = xgetbv(XCR_XFEATURE_ENABLED_MASK); + supported_xcr0 = host_xcr0 & KVM_SUPPORTED_XCR0; + } kvm_lapic_init(); if (pi_inject_timer == -1) diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h index 3624665acee4..02b49ee49e24 100644 --- a/arch/x86/kvm/x86.h +++ b/arch/x86/kvm/x86.h @@ -280,13 +280,8 @@ int x86_emulate_instruction(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, int emulation_type, void *insn, int insn_len); enum exit_fastpath_completion handle_fastpath_set_msr_irqoff(struct kvm_vcpu *vcpu); -#define KVM_SUPPORTED_XCR0 (XFEATURE_MASK_FP | XFEATURE_MASK_SSE \ - | XFEATURE_MASK_YMM | XFEATURE_MASK_BNDREGS \ - | XFEATURE_MASK_BNDCSR | XFEATURE_MASK_AVX512 \ - | XFEATURE_MASK_PKRU) extern u64 host_xcr0; - -extern u64 kvm_supported_xcr0(void); +extern u64 supported_xcr0; extern unsigned int min_timer_period_us; -- 2.24.1