diff --git a/drivers/char/drm/drm_vm.c b/drivers/char/drm/drm_vm.c
index 9e3f25946590622587cdbb08c76c3ef16b808b0c..239ac33a6e1040ba760a49f6c37a0701cddf45ec 100644
--- a/drivers/char/drm/drm_vm.c
+++ b/drivers/char/drm/drm_vm.c
@@ -41,7 +41,7 @@
 static void drm_vm_open(struct vm_area_struct *vma);
 static void drm_vm_close(struct vm_area_struct *vma);
 
-pgprot_t drm_io_prot(uint32_t map_type, struct vm_area_struct *vma)
+static pgprot_t drm_io_prot(uint32_t map_type, struct vm_area_struct *vma)
 {
 	pgprot_t tmp = vm_get_page_prot(vma->vm_flags);