sync with OpenBSD -current

sys/dev/pci/drm/drm_fb_helper.c

@@ -647,6 +647,17 @@ static void drm_fb_helper_add_damage_clip(struct drm_fb_helper *helper, u32 x, u
 static void drm_fb_helper_damage(struct drm_fb_helper *helper, u32 x, u32 y,
 				 u32 width, u32 height)
 {
+	/*
+	 * This function may be invoked by panic() to flush the frame
+	 * buffer, where all CPUs except the panic CPU are stopped.
+	 * During the following schedule_work(), the panic CPU needs
+	 * the worker_pool lock, which might be held by a stopped CPU,
+	 * causing schedule_work() and panic() to block. Return early on
+	 * oops_in_progress to prevent this blocking.
+	 */
+	if (oops_in_progress)
+		return;
+
 	drm_fb_helper_add_damage_clip(helper, x, y, width, height);
 
 	schedule_work(&helper->damage_work);