diff --git a/arch/x86/pci/i386.c b/arch/x86/pci/i386.c
index a70a85de5e84e91a7124484625d16e0208048fc3..52e656f1778133bdbc5628e21f25842dd23d8dce 100644
--- a/arch/x86/pci/i386.c
+++ b/arch/x86/pci/i386.c
@@ -280,6 +280,15 @@ int pci_mmap_page_range(struct pci_dev *dev, struct vm_area_struct *vma,
 		return -EINVAL;
 
 	prot = pgprot_val(vma->vm_page_prot);
+
+	/*
+ 	 * Return error if pat is not enabled and write_combine is requested.
+ 	 * Caller can followup with UC MINUS request and add a WC mtrr if there
+ 	 * is a free mtrr slot.
+ 	 */
+	if (!pat_enabled && write_combine)
+		return -EINVAL;
+
 	if (pat_enabled && write_combine)
 		prot |= _PAGE_CACHE_WC;
 	else if (pat_enabled || boot_cpu_data.x86 > 3)