[coreboot-gerrit] Change in ...coreboot[master]: cpu/intel/common: Fix generated exception if VMX is not supported

[HAOUAS Elyes (Code Review)]

HAOUAS Elyes has uploaded this change for review. ( https://review.coreboot.org/c/coreboot/+/30713

Change subject: cpu/intel/common: Fix generated exception if VMX is not supported
......................................................................

cpu/intel/common: Fix generated exception if VMX is not supported

Reading rdmsr(IA32_FEATURE_CONTROL) in function et_feature_ctrl_lock()
will generate an exception if the CPU do not support this MSR.
Tested on pentium4 (CPUID F65).

Change-Id: I72e138e3bcffe1dcd4e20739a8d07c9abfab4f80
Signed-off-by: Elyes HAOUAS 
---
M src/cpu/intel/common/common_init.c
1 file changed, 9 insertions(+), 8 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/13/30713/1

diff --git a/src/cpu/intel/common/common_init.c b/src/cpu/intel/common/common_init.c
index 4f3bcac..882db3e 100644
--- a/src/cpu/intel/common/common_init.c
+++ b/src/cpu/intel/common/common_init.c
@@ -23,6 +23,14 @@

void set_vmx_and_lock(void)
 {
+	uint32_t feature_flag = cpu_get_feature_flags_ecx();
+
+	/* Check that the VMX is supported before reading or writing the MSR. */
+	if (!((feature_flag & CPUID_VMX) || (feature_flag & CPUID_SMX))) {
+		printk(BIOS_DEBUG, "CPU doesn't support VMX; exiting\n");
+		return;
+	}
+
    set_feature_ctrl_vmx();
    set_feature_ctrl_lock();
 }
@@ -30,16 +38,9 @@
 void set_feature_ctrl_vmx(void)
 {
    msr_t msr;
-	uint32_t feature_flag;
+	uint32_t feature_flag = cpu_get_feature_flags_ecx();
    int enable = IS_ENABLED(CONFIG_ENABLE_VMX);

-	feature_flag = cpu_get_feature_flags_ecx();
-	/* Check that the VMX is supported before reading or writing the MSR. */
-	if (!((feature_flag & CPUID_VMX) || (feature_flag & CPUID_SMX))) {
-		printk(BIOS_DEBUG, "CPU doesn't support VMX; exiting\n");
-		return;
-	}
-
    msr = rdmsr(IA32_FEATURE_CONTROL);

if (msr.lo & (1 << 0)) {