[PATCH v3 07/14] drm/panic: Return from screen_user if display is too small

[Thomas Zimmermann]

Return an error if the display is too small to display at least a
single character. If the panic handler cannot display any message
it does at least not destroy the current output, which might help
with identifying the problem.

This change duplicates the logic from screen_kmsg output.

Signed-off-by: Thomas Zimmermann <tzimmermann at suse.de>
---
 drivers/gpu/drm/drm_panic.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/drm_panic.c b/drivers/gpu/drm/drm_panic.c
index f597ef04c5bc..c317afc76669 100644
--- a/drivers/gpu/drm/drm_panic.c
+++ b/drivers/gpu/drm/drm_panic.c
@@ -486,7 +486,7 @@ static int draw_panic_screen_user(struct drm_scanout_buffer *sb, u32 fg_color, u
 	struct drm_rect r_screen, r_logo, r_msg;
 	unsigned int msg_width, msg_height;
 
-	if (!font)
+	if (!font || font->width > sb->width)
 		return -EINVAL;
 
 	fg_color = drm_draw_color_from_xrgb8888(fg_color, sb->format->format);
-- 
2.55.0