KVM: VMX: Properly return error to userspace on vmentry failure

The vmexit handler returns KVM_EXIT_UNKNOWN since there is no handler
for vmentry failures. This intercepts vmentry failures and returns
KVM_FAIL_ENTRY to userspace instead.

Signed-off-by: Mohammed Gamal <m.gamal005@gmail.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>

1 files changed, 7 insertions, 0 deletions

diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index e71c731433ee..8c9085d44c37 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -3665,6 +3665,13 @@ static int vmx_handle_exit(struct kvm_vcpu *vcpu)
         if (enable_ept && is_paging(vcpu))
                 vcpu->arch.cr3 = vmcs_readl(GUEST_CR3);
 
+        if (exit_reason & VMX_EXIT_REASONS_FAILED_VMENTRY) {
+                vcpu->run->exit_reason = KVM_EXIT_FAIL_ENTRY;
+                vcpu->run->fail_entry.hardware_entry_failure_reason
+                        = exit_reason;
+                return 0;
+        }
+
         if (unlikely(vmx->fail)) {
                 vcpu->run->exit_reason = KVM_EXIT_FAIL_ENTRY;
                 vcpu->run->fail_entry.hardware_entry_failure_reason