Index: ieee80211_dfs.c
===================================================================
--- ieee80211_dfs.c	(revision 196635)
+++ ieee80211_dfs.c	(working copy)
@@ -235,7 +235,7 @@
 	}
 	if (oldest != now) {
 		/* arrange to process next channel up for a status change */
-		callout_schedule(&dfs->nol_timer, oldest + NOL_TIMEOUT);
+		callout_schedule(&dfs->nol_timer, oldest + NOL_TIMEOUT - now);
 	}
 }