diff options
| author | Sean Christopherson <[email protected]> | 2019-12-20 20:45:09 -0800 |
|---|---|---|
| committer | Borislav Petkov <[email protected]> | 2020-01-13 19:19:32 +0100 |
| commit | a4d0b2fdbcf75ef6654713c83c316ea3a661ddc3 (patch) | |
| tree | 3fe066e0bc85f112fcbfd6bcb31026acc5e5c10d | |
| parent | 21bd3467a58ea51ccc0b1d9bcb86dadf1640a002 (diff) | |
KVM: VMX: Use VMX feature flag to query BIOS enabling
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 <[email protected]>
Signed-off-by: Borislav Petkov <[email protected]>
Link: https://lkml.kernel.org/r/[email protected]
| -rw-r--r-- | arch/x86/kvm/vmx/vmx.c | 27 |
1 files 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) |