diff --git a/drivers/video/fbdev/core/fbcon.c b/drivers/video/fbdev/core/fbcon.c
index 66167830fefd..f759e21ca2c8 100644
--- a/drivers/video/fbdev/core/fbcon.c
+++ b/drivers/video/fbdev/core/fbcon.c
@@ -1058,8 +1058,10 @@ static const char *fbcon_startup(void)
 		vc->vc_font.height = font->height;
 		vc->vc_font.data = (void *)(p->fontdata = font->data);
 		vc->vc_font.charcount = 256; /* FIXME  Need to support more fonts */
+		BUG_ON(p->userfont != is_dyn_font(vc->vc_font.data));
 	} else {
 		p->fontdata = vc->vc_font.data;
+		BUG_ON(p->userfont != is_dyn_font(vc->vc_font.data));
 	}
 
 	cols = FBCON_SWAP(ops->rotate, info->var.xres, info->var.yres);
@@ -1125,6 +1127,7 @@ static void fbcon_init(struct vc_data *vc, int init)
 
 			if (p->userfont)
 				REFCOUNT(p->fontdata)++;
+			BUG_ON(p->userfont != is_dyn_font(vc->vc_font.data));
 		} else {
 			const struct font_desc *font = NULL;
 
@@ -1138,6 +1141,7 @@ static void fbcon_init(struct vc_data *vc, int init)
 			vc->vc_font.data = (void *)(p->fontdata = font->data);
 			vc->vc_font.charcount = 256; /* FIXME  Need to
 							support more fonts */
+			BUG_ON(p->userfont != is_dyn_font(vc->vc_font.data));
 		}
 	}
 
@@ -1444,6 +1448,7 @@ static void fbcon_set_disp(struct fb_info *info, struct fb_var_screeninfo *var,
 		vc->vc_font.width = (*default_mode)->vc_font.width;
 		vc->vc_font.height = (*default_mode)->vc_font.height;
 		p->userfont = t->userfont;
+		BUG_ON(p->userfont != is_dyn_font(vc->vc_font.data));
 		if (p->userfont)
 			REFCOUNT(p->fontdata)++;
 	}
@@ -2613,6 +2618,7 @@ static int fbcon_do_set_font(struct vc_data *vc, int w, int h,
 	vc->vc_font.data = (void *)(p->fontdata = data);
 	if ((p->userfont = userfont))
 		REFCOUNT(data)++;
+	BUG_ON(p->userfont != is_dyn_font(vc->vc_font.data));
 	vc->vc_font.width = w;
 	vc->vc_font.height = h;
 	if (vc->vc_hi_font_mask && cnt == 256)
diff --git a/include/linux/font.h b/include/linux/font.h
index 51b91c8b69d5..9a4f6d96f75f 100644
--- a/include/linux/font.h
+++ b/include/linux/font.h
@@ -51,6 +51,10 @@ extern const struct font_desc	font_vga_8x8,
 
 extern const struct font_desc *find_font(const char *name);
 
+/* Check if font data seems to be dynamic */
+
+extern bool is_dyn_font(const void *data);
+
 /* Get the default font for a specific screen size */
 
 extern const struct font_desc *get_default_font(int xres, int yres,
diff --git a/lib/fonts/fonts.c b/lib/fonts/fonts.c
index e7258d8c252b..777c19d299bf 100644
--- a/lib/fonts/fonts.c
+++ b/lib/fonts/fonts.c
@@ -19,6 +19,7 @@
 #include <asm/setup.h>
 #endif
 #include <linux/font.h>
+#include <linux/slab.h>
 
 static const struct font_desc *fonts[] = {
 #ifdef CONFIG_FONT_8x8
@@ -88,6 +89,22 @@ const struct font_desc *find_font(const char *name)
 }
 EXPORT_SYMBOL(find_font);
 
+/**
+ *	is_dyn_font - check if font data seems to be dynamic
+ *	@data: font data to examine
+ *
+ *	Returns true if @data seems to be dynamic, false otherwise.
+ */
+bool is_dyn_font(const void *data)
+{
+	unsigned int i;
+
+	for (i = 0; i < num_fonts; i++)
+		if (fonts[i]->data == data)
+			return false;
+	return !ZERO_OR_NULL_PTR(data) && !IS_ERR(data);
+}
+EXPORT_SYMBOL(is_dyn_font);
 
 /**
  *	get_default_font - get default font