diff --git a/sys/compat/linuxkpi/common/include/linux/io.h b/sys/compat/linuxkpi/common/include/linux/io.h
index f89c150e7a3..4dfc04b3f3f 100644
--- a/sys/compat/linuxkpi/common/include/linux/io.h
+++ b/sys/compat/linuxkpi/common/include/linux/io.h
@@ -544,6 +544,9 @@ arch_io_reserve_memtype_wc(resource_size_t start, resource_size_t size)
 #if defined(__amd64__)
 	void *va;
 
+	if (!PHYS_IN_DMAP(start) || !PHYS_IN_DMAP(start + size))
+		return (-EINVAL);
+
 	va = PHYS_TO_DMAP(start);
 	return (-pmap_change_attr(va, size, VM_MEMATTR_WRITE_COMBINING));
 #else
@@ -557,8 +560,10 @@ arch_io_free_memtype_wc(resource_size_t start, resource_size_t size)
 #if defined(__amd64__)
 	void *va;
 
-	va = PHYS_TO_DMAP(start);
+	if (!PHYS_IN_DMAP(start) || !PHYS_IN_DMAP(start + size))
+		return;
 
+	va = PHYS_TO_DMAP(start);
 	pmap_change_attr(va, size, VM_MEMATTR_WRITE_BACK);
 #endif
 }