diff options
Diffstat (limited to 'src/cpu/intel/model_206ax/model_206ax_init.c')
| -rw-r--r-- | src/cpu/intel/model_206ax/model_206ax_init.c | 26 |
1 files changed, 14 insertions, 12 deletions
diff --git a/src/cpu/intel/model_206ax/model_206ax_init.c b/src/cpu/intel/model_206ax/model_206ax_init.c index 47c7707548..bcd68657e0 100644 --- a/src/cpu/intel/model_206ax/model_206ax_init.c +++ b/src/cpu/intel/model_206ax/model_206ax_init.c @@ -122,30 +122,32 @@ static void enable_vmx(void) msr_t msr; int enable = CONFIG_ENABLE_VMX; + regs = cpuid(1); + /* Check that the VMX is supported before reading or writing the MSR. */ + if (!((regs.ecx & CPUID_VMX) || (regs.ecx & CPUID_SMX))) + return; + msr = rdmsr(IA32_FEATURE_CONTROL); if (msr.lo & (1 << 0)) { - printk(BIOS_ERR, "VMX is locked, so enable_vmx will do nothing\n"); + printk(BIOS_ERR, "VMX is locked, so %s will do nothing\n", __func__); /* VMX locked. If we set it again we get an illegal * instruction */ return; } - regs = cpuid(1); + /* The IA32_FEATURE_CONTROL MSR may initialize with random values. + * It must be cleared regardless of VMX config setting. + */ + msr.hi = msr.lo = 0; + printk(BIOS_DEBUG, "%s VMX\n", enable ? "Enabling" : "Disabling"); - if (regs.ecx & CPUID_VMX) { - if (enable) - msr.lo |= (1 << 2); - else - msr.lo &= ~(1 << 2); - if (regs.ecx & CPUID_SMX) { - if (enable) + if (enable) { + msr.lo |= (1 << 2); + if (regs.ecx & CPUID_SMX) msr.lo |= (1 << 1); - else - msr.lo &= ~(1 << 1); - } } wrmsr(IA32_FEATURE_CONTROL, msr); |