===== DF-4913 baseline run =====
--- vmstat -m ath_hal BEFORE ---
            ath_hal     600   2.93M       0    390M      800
--- kldload + trigger ---
KLDLOAD_OK
hw.v14leak: 0 -> 0
--- vmstat -m ath_hal AFTER trigger (600 failed attaches) ---
            ath_hal   1.17K   5.86M       0    390M    1.56K
--- kldunload ---
KLDUNLOAD_OK
--- vmstat -m ath_hal AFTER unload (leak is permanent) ---
            ath_hal   1.17K   5.86M       0    390M    1.56K