backend/drm: fail instead of stripping a modifier
We shouldn't strip a modifiers from buffers, because the will make
the kernel re-interpret the data as LINEAR on most drivers,
resulting in an incorrect output on screen.
@@ -228,6 +228,14 @@ uint32_t get_fb_for_bo(struct gbm_bo *bo, bool with_modifiers) {
wlr_log_errno(WLR_ERROR, "Unable to add DRM framebuffer");
}
} else {
+ if (gbm_bo_get_modifier(bo) != DRM_FORMAT_MOD_INVALID &&
+ gbm_bo_get_modifier(bo) != DRM_FORMAT_MOD_LINEAR) {
+ wlr_log(WLR_ERROR, "Failed to add DRM frame-buffer: "
+ "BO has modifier 0x%"PRIX64" but KMS doesn't support modifiers",
+ gbm_bo_get_modifier(bo));
+ return 0;
+ }
+
if (drmModeAddFB2(fd, width, height, format, handles, strides,
offsets, &id, 0)) {
wlr_log_errno(WLR_DEBUG,
