[PATCH v3 11/19] KVM: VMX: Check for full VMX support when verifying CPU compatibility

Sean Christopherson
2019-11-19T03:12:55Z

Explicitly check the current CPU's VMX feature flag when verifying
compatibility across physical CPUs. This effectively adds a check on
IA32_FEATURE_CONTROL to ensure that VMX is fully enabled on all CPUs.

Reviewed-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
---
arch/x86/kvm/vmx/vmx.c | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index eff28130cb54..d9bd99977464 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -6831,6 +6831,11 @@ static int __init vmx_check_processor_compat(void)
struct vmcs_config vmcs_conf;
struct vmx_capability vmx_cap;

+ if (!this_cpu_has(X86_FEATURE_VMX)) {
+ pr_err("kvm: VMX is disabled on CPU %d\n", smp_processor_id());
+ return -EIO;
+ }
+
if (setup_vmcs_config(&vmcs_conf, &vmx_cap) < 0)
return -EIO;
if (nested)
--
2.24.0