From 190b667ac20e8175758f4a3a0f13c4d990e6af7e Mon Sep 17 00:00:00 2001 From: Yang Zhang Date: Fri, 4 Oct 2013 12:28:14 +0200 Subject: Nested VMX: check VMX capability before read VMX related MSRs VMX MSRs only available when the CPU support the VMX feature. In addition, VMX_TRUE* MSRs only available when bit 55 of VMX_BASIC MSR is set. Signed-off-by: Yang Zhang Cleanup. Signed-off-by: Jan Beulich Acked-by: Jun Nakajima --- xen/arch/x86/hvm/vmx/vmcs.c | 3 +++ xen/arch/x86/hvm/vmx/vvmx.c | 21 +++++++++++++++++++++ xen/include/asm-x86/hvm/vmx/vmcs.h | 2 ++ 3 files changed, 26 insertions(+) diff --git a/xen/arch/x86/hvm/vmx/vmcs.c b/xen/arch/x86/hvm/vmx/vmcs.c index 89a22a42b1..b64ec6fa13 100644 --- a/xen/arch/x86/hvm/vmx/vmcs.c +++ b/xen/arch/x86/hvm/vmx/vmcs.c @@ -78,6 +78,7 @@ static DEFINE_PER_CPU(struct list_head, active_vmcs_list); static DEFINE_PER_CPU(bool_t, vmxon); static u32 vmcs_revision_id __read_mostly; +u64 __read_mostly vmx_basic_msr; static void __init vmx_display_features(void) { @@ -301,6 +302,8 @@ static int vmx_init_vmcs_config(void) vmx_vmexit_control = _vmx_vmexit_control; vmx_vmentry_control = _vmx_vmentry_control; cpu_has_vmx_ins_outs_instr_info = !!(vmx_basic_msr_high & (1U<<22)); + vmx_basic_msr = ((u64)vmx_basic_msr_high << 32) | + vmx_basic_msr_low; vmx_display_features(); } else diff --git a/xen/arch/x86/hvm/vmx/vvmx.c b/xen/arch/x86/hvm/vmx/vvmx.c index d476f03dcd..b911eb1499 100644 --- a/xen/arch/x86/hvm/vmx/vvmx.c +++ b/xen/arch/x86/hvm/vmx/vvmx.c @@ -1815,12 +1815,33 @@ int nvmx_handle_invvpid(struct cpu_user_regs *regs) int nvmx_msr_read_intercept(unsigned int msr, u64 *msr_content) { struct vcpu *v = current; + unsigned int ecx, dummy; u64 data = 0, host_data = 0; int r = 1; if ( !nestedhvm_enabled(v->domain) ) return 0; + /* VMX capablity MSRs are available only when guest supports VMX. */ + hvm_cpuid(0x1, &dummy, &dummy, &ecx, &dummy); + if ( !(ecx & cpufeat_mask(X86_FEATURE_VMXE)) ) + return 0; + + /* + * Those MSRs are available only when bit 55 of + * MSR_IA32_VMX_BASIC is set. + */ + switch ( msr ) + { + case MSR_IA32_VMX_TRUE_PINBASED_CTLS: + case MSR_IA32_VMX_TRUE_PROCBASED_CTLS: + case MSR_IA32_VMX_TRUE_EXIT_CTLS: + case MSR_IA32_VMX_TRUE_ENTRY_CTLS: + if ( !(vmx_basic_msr & VMX_BASIC_DEFAULT1_ZERO) ) + return 0; + break; + } + rdmsrl(msr, host_data); /* diff --git a/xen/include/asm-x86/hvm/vmx/vmcs.h b/xen/include/asm-x86/hvm/vmx/vmcs.h index 38c24948d7..8c123c7655 100644 --- a/xen/include/asm-x86/hvm/vmx/vmcs.h +++ b/xen/include/asm-x86/hvm/vmx/vmcs.h @@ -284,6 +284,8 @@ extern bool_t cpu_has_vmx_ins_outs_instr_info; */ #define VMX_BASIC_DEFAULT1_ZERO (1ULL << 55) +extern u64 vmx_basic_msr; + /* Guest interrupt status */ #define VMX_GUEST_INTR_STATUS_SUBFIELD_BITMASK 0x0FF #define VMX_GUEST_INTR_STATUS_SVI_OFFSET 8 -- cgit v1.2.3