HV: add MTRR capability check when CPU boot

- to avoid reading operations on MTRR registers if no MTRR feature support on current platform in "init_mtrr()". Signed-off-by: Yonghua Huang <yonghua.huang@intel.com>
projectacrn · Jun 28, 2018 · 9beb1b9 · 9beb1b9
1 parent f67951b
commit 9beb1b9
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Showing 2 changed files with 6 additions and 2 deletions.
diff --git a/hypervisor/arch/x86/cpu.c b/hypervisor/arch/x86/cpu.c
@@ -219,6 +219,11 @@ static int hardware_detect_support(void)
 		return -ENODEV;
 	}
 
+	if (!cpu_has_cap(X86_FEATURE_MTRR)) {
+		pr_fatal("%s, MTRR not supported\n", __func__);
+		return -ENODEV;
+	}
+
 	if (!cpu_has_cap(X86_FEATURE_VMX)) {
 		pr_fatal("%s, vmx not supported\n", __func__);
 		return -ENODEV;

diff --git a/hypervisor/arch/x86/mtrr.c b/hypervisor/arch/x86/mtrr.c
@@ -103,9 +103,8 @@ void init_mtrr(struct vcpu *vcpu)
 	vcpu->mtrr.def_type.bits.fixed_enable = 1;
 	vcpu->mtrr.def_type.bits.type = MTRR_MEM_TYPE_UC;
 
-	if (is_vm0(vcpu->vm) && cpu_has_cap(X86_FEATURE_MTRR)) {
+	if (is_vm0(vcpu->vm))
 		cap.value = msr_read(MSR_IA32_MTRR_CAP);
-	}
 
 	for (i = 0; i < FIXED_RANGE_MTRR_NUM; i++) {
 		if (cap.bits.fix) {