Replace KVM's manual checks on IA32_FEAT_CTL with a query on the boot CPU's MSR_IA32_FEAT_CTL and VMX feature flags. The MSR_IA32_FEAT_CTL indicates that IA32_FEAT_CTL has been configured and that dependent features are accurately reflected in cpufeatures, e.g. the VMX flag is now cleared during boot if VMX isn't fully enabled via IA32_FEAT_CTL, including the case where the MSR isn't supported.
Signed-off-by: Sean Christopherson sean.j.christopherson@intel.com --- arch/x86/kvm/vmx/vmx.c | 27 ++------------------------- 1 file changed, 2 insertions(+), 25 deletions(-)
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index a026334ffc58..06e0e5262704 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -2204,31 +2204,8 @@ static __init int cpu_has_kvm_support(void)
static __init int vmx_disabled_by_bios(void) { - u64 msr; - - rdmsrl(MSR_IA32_FEAT_CTL, msr); - - if (unlikely(!(msr & FEAT_CTL_LOCKED))) - return 1; - - /* launched w/ TXT and VMX disabled */ - if (!(msr & FEAT_CTL_VMX_ENABLED_INSIDE_SMX) && - tboot_enabled()) - return 1; - /* launched w/o TXT and VMX only enabled w/ TXT */ - if (!(msr & FEAT_CTL_VMX_ENABLED_OUTSIDE_SMX) && - (msr & FEAT_CTL_VMX_ENABLED_INSIDE_SMX) && - !tboot_enabled()) { - pr_warn("kvm: disable TXT in the BIOS or " - "activate TXT before enabling KVM\n"); - return 1; - } - /* launched w/o TXT and VMX disabled */ - if (!(msr & FEAT_CTL_VMX_ENABLED_OUTSIDE_SMX) && - !tboot_enabled()) - return 1; - - return 0; + return !boot_cpu_has(X86_FEATURE_MSR_IA32_FEAT_CTL) || + !boot_cpu_has(X86_FEATURE_VMX); }
static void kvm_cpu_vmxon(u64 addr)