diff --git a/drivers/video/fb.c b/drivers/video/fb.c
index 4263027bf..c36b9adce 100644
--- a/drivers/video/fb.c
+++ b/drivers/video/fb.c
@@ -78,6 +78,8 @@ static int fb_setup_mode(struct device_d *dev, struct param_d *param,
 
 	if (!info->line_length)
 		info->line_length = info->xres * (info->bits_per_pixel >> 3);
+	if (!info->screen_size)
+		info->screen_size = info->line_length * info->yres;
 
 	if (!ret) {
 		dev->resource[0].start = (resource_size_t)info->screen_base;
diff --git a/include/fb.h b/include/fb.h
index 98d5a0382..22fa9b130 100644
--- a/include/fb.h
+++ b/include/fb.h
@@ -86,6 +86,7 @@ struct fb_info {
 	struct device_d dev;		/* This is this fb device */
 
 	void *screen_base;
+	unsigned long screen_size;
 
 	void *priv;