fbcon: clear the logo bitmap from the margin area

Explicitly clear_margins when clearing the logo, in case the font dimensions
are non-integral to the framebuffer dimensions.

Signed-off-by: Kamal Mostafa <kamal@whence.com>
Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/video/console/fbcon.c

@@ -1242,8 +1242,16 @@ static void fbcon_clear(struct vc_data *vc, int sy, int sx, int height,
 	if (!height || !width)
 		return;
 
-	if (sy < vc->vc_top && vc->vc_top == logo_lines)
+	if (sy < vc->vc_top && vc->vc_top == logo_lines) {
 		vc->vc_top = 0;
+		/*
+		 * If the font dimensions are not an integral of the display
+		 * dimensions then the ops->clear below won't end up clearing
+		 * the margins.  Call clear_margins here in case the logo
+		 * bitmap stretched into the margin area.
+		 */
+		fbcon_clear_margins(vc, 0);
+	}
 
 	/* Split blits that cross physical y_wrap boundary */