This is fixed in 3.8, but is too much to backport for now.
As there's no point in abrt telling us this is broken, we'll just silence it.

--- linux-3.7.7-201.fc18.x86_64/drivers/net/wireless/brcm80211/brcmsmac/main.c~	2013-02-12 11:36:18.787973130 -0500
+++ linux-3.7.7-201.fc18.x86_64/drivers/net/wireless/brcm80211/brcmsmac/main.c	2013-02-12 11:37:02.950969879 -0500
@@ -7993,8 +7993,6 @@ void brcms_c_wait_for_tx_completion(stru
 		if (--timeout == 0)
 			break;
 	}
-
-	WARN_ON_ONCE(timeout == 0);
 }
 
 void brcms_c_set_beacon_listen_interval(struct brcms_c_info *wlc, u8 interval)