hv:Check if VMX capability is locked with incorrect value

Check if the VMX capability is locked with incorrect value,
at the time when HV do the hardware capability detect.

Tracked-On: #861
Signed-off-by: Mingqiang Chi <mingqiang.chi@intel.com>
Reviewed-by: Junjie Mao <junjie.mao@intel.com>
Acked-by: Eddie Dong <eddie.dong@intel.com>

Author: mingqiangchi

hypervisor/arch/x86/cpu.c

@@ -252,6 +252,11 @@ static int hardware_detect_support(void)
 		return -ENODEV;
 	}
 
+	if (is_vmx_disabled()) {
+		pr_fatal("%s, VMX can not be enabled\n", __func__);
+		return -ENODEV;
+	}
+
 	ret = check_vmx_mmu_cap();
 	if (ret != 0) {
 		return ret;

hypervisor/arch/x86/vmx.c

@@ -26,6 +26,21 @@ static uint64_t cr4_host_mask;
 static uint64_t cr4_always_on_mask;
 static uint64_t cr4_always_off_mask;
 
+bool is_vmx_disabled(void)
+{
+	uint64_t msr_val;
+
+	/* Read Feature ControL MSR */
+	msr_val = msr_read(MSR_IA32_FEATURE_CONTROL);
+
+	/* Check if feature control is locked and vmx cannot be enabled */
+	if ((msr_val & MSR_IA32_FEATURE_CONTROL_LOCK) != 0U &&
+		(msr_val & MSR_IA32_FEATURE_CONTROL_VMX_NO_SMX) == 0U) {
+		return true;
+	}
+	return false;
+}
+
 static inline int exec_vmxon(void *addr)
 {
 	uint64_t rflags;
@@ -41,14 +56,7 @@ static inline int exec_vmxon(void *addr)
 	tmp64 = msr_read(MSR_IA32_FEATURE_CONTROL);
 
 	/* Determine if feature control is locked */
-	if ((tmp64 & MSR_IA32_FEATURE_CONTROL_LOCK) != 0U) {
-		/* See if VMX enabled */
-		if ((tmp64 & MSR_IA32_FEATURE_CONTROL_VMX_NO_SMX) == 0U) {
-			/* Return error - VMX can't be enabled */
-			pr_err("%s, VMX can't be enabled\n", __func__);
-			status = -EINVAL;
-		}
-	} else {
+	if ((tmp64 & MSR_IA32_FEATURE_CONTROL_LOCK) == 0U) {
 		/* Lock and enable VMX support */
 		tmp64 |= (MSR_IA32_FEATURE_CONTROL_LOCK |
 			  MSR_IA32_FEATURE_CONTROL_VMX_NO_SMX);

hypervisor/include/arch/x86/vmx.h

@@ -448,6 +448,7 @@ int vmx_wrmsr_pat(struct vcpu *vcpu, uint64_t value);
 
 void vmx_write_cr0(struct vcpu *vcpu, uint64_t cr0);
 void vmx_write_cr4(struct vcpu *vcpu, uint64_t cr4);
+bool is_vmx_disabled(void);
 
 static inline enum vm_cpu_mode get_vcpu_mode(const struct vcpu *vcpu)
 {