kvm: nVMX: Check "load IA32_PAT" VM-entry control on vmentry

According to section "Checking and Loading Guest State" in Intel SDM vol
3C, the following check is performed on vmentry:

    If the "load IA32_PAT" VM-entry control is 1, the value of the field
    for the IA32_PAT MSR must be one that could be written by WRMSR
    without fault at CPL 0. Specifically, each of the 8 bytes in the
    field must have one of the values 0 (UC), 1 (WC), 4 (WT), 5 (WP),
    6 (WB), or 7 (UC-).

Signed-off-by: Krish Sadhukhan <krish.sadhukhan@oracle.com>
Reviewed-by: Karl Heubaum <karl.heubaum@oracle.com>
Suggested-by: Sean Christopherson <sean.j.christopherson@intel.com>
Reviewed-by: Sean Christopherson <sean.j.christopherson@intel.com>
Reviewed-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
index 37cd5eb..8dc6a43 100644 (file)
--- a/arch/x86/kvm/vmx/nested.c
+++ b/arch/x86/kvm/vmx/nested.c
@@ -2696,6 +2696,10 @@ static int nested_vmx_check_vmentry_postreqs(struct kvm_vcpu *vcpu,
            !nested_guest_cr4_valid(vcpu, vmcs12->guest_cr4))
                return 1;
 
+       if ((vmcs12->vm_entry_controls & VM_ENTRY_LOAD_IA32_PAT) &&
+           !kvm_pat_valid(vmcs12->guest_ia32_pat))
+               return 1;
+
        if (nested_vmx_check_vmcs_link_ptr(vcpu, vmcs12)) {
                *exit_qual = ENTRY_FAIL_VMCS_LINK_PTR;
                return 1;