From 7f5581f592984901620d34aa86a730092ae65092 Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Mon, 2 Mar 2020 15:56:24 -0800 Subject: [PATCH] KVM: x86: Use supported_xcr0 to detect MPX support Query supported_xcr0 when checking for MPX support instead of invoking ->mpx_supported() and drop ->mpx_supported() as kvm_mpx_supported() was its last user. Rename vmx_mpx_supported() to cpu_has_vmx_mpx() to better align with VMX/VMCS nomenclature. Modify VMX's adjustment of xcr0 to call cpus_has_vmx_mpx() (renamed from vmx_mpx_supported()) directly to avoid reading supported_xcr0 before it's fully configured. No functional change intended. Reviewed-by: Xiaoyao Li Reviewed-by: Vitaly Kuznetsov Signed-off-by: Sean Christopherson [Test that *all* bits are set. - Paolo] Signed-off-by: Paolo Bonzini --- arch/x86/include/asm/kvm_host.h | 2 +- arch/x86/kvm/cpuid.c | 4 ++-- arch/x86/kvm/svm.c | 6 ------ arch/x86/kvm/vmx/capabilities.h | 2 +- arch/x86/kvm/vmx/vmx.c | 3 +-- 5 files changed, 5 insertions(+), 12 deletions(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 6ac67b6d66929..f817ddf876b5a 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -1177,7 +1177,7 @@ struct kvm_x86_ops { struct x86_exception *exception); void (*handle_exit_irqoff)(struct kvm_vcpu *vcpu, enum exit_fastpath_completion *exit_fastpath); - bool (*mpx_supported)(void); + bool (*xsaves_supported)(void); bool (*umip_emulated)(void); bool (*pt_supported)(void); diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index 1eb775c33c4e1..7f3f1a683853f 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -47,8 +47,8 @@ static u32 xstate_required_size(u64 xstate_bv, bool compacted) bool kvm_mpx_supported(void) { - return ((host_xcr0 & (XFEATURE_MASK_BNDREGS | XFEATURE_MASK_BNDCSR)) - && kvm_x86_ops->mpx_supported()); + return (supported_xcr0 & (XFEATURE_MASK_BNDREGS | XFEATURE_MASK_BNDCSR)) + == (XFEATURE_MASK_BNDREGS | XFEATURE_MASK_BNDCSR); } EXPORT_SYMBOL_GPL(kvm_mpx_supported); diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index 5ba2ef1b45778..7521f72b1067a 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -6081,11 +6081,6 @@ static bool svm_invpcid_supported(void) return false; } -static bool svm_mpx_supported(void) -{ - return false; -} - static bool svm_xsaves_supported(void) { return boot_cpu_has(X86_FEATURE_XSAVES); @@ -7469,7 +7464,6 @@ static struct kvm_x86_ops svm_x86_ops __ro_after_init = { .rdtscp_supported = svm_rdtscp_supported, .invpcid_supported = svm_invpcid_supported, - .mpx_supported = svm_mpx_supported, .xsaves_supported = svm_xsaves_supported, .umip_emulated = svm_umip_emulated, .pt_supported = svm_pt_supported, diff --git a/arch/x86/kvm/vmx/capabilities.h b/arch/x86/kvm/vmx/capabilities.h index 80eec8cffbe26..c00e26570198e 100644 --- a/arch/x86/kvm/vmx/capabilities.h +++ b/arch/x86/kvm/vmx/capabilities.h @@ -101,7 +101,7 @@ static inline bool cpu_has_load_perf_global_ctrl(void) (vmcs_config.vmexit_ctrl & VM_EXIT_LOAD_IA32_PERF_GLOBAL_CTRL); } -static inline bool vmx_mpx_supported(void) +static inline bool cpu_has_vmx_mpx(void) { return (vmcs_config.vmexit_ctrl & VM_EXIT_CLEAR_BNDCFGS) && (vmcs_config.vmentry_ctrl & VM_ENTRY_LOAD_BNDCFGS); diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index e03b4d0370794..59571cdd62fd5 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -7660,7 +7660,7 @@ static __init int hardware_setup(void) WARN_ONCE(host_bndcfgs, "KVM: BNDCFGS in host will be lost"); } - if (!kvm_mpx_supported()) + if (!cpu_has_vmx_mpx()) supported_xcr0 &= ~(XFEATURE_MASK_BNDREGS | XFEATURE_MASK_BNDCSR); @@ -7927,7 +7927,6 @@ static struct kvm_x86_ops vmx_x86_ops __ro_after_init = { .check_intercept = vmx_check_intercept, .handle_exit_irqoff = vmx_handle_exit_irqoff, - .mpx_supported = vmx_mpx_supported, .xsaves_supported = vmx_xsaves_supported, .umip_emulated = vmx_umip_emulated, .pt_supported = vmx_pt_supported, -- 2.30.2