From: Luis R. Rodriguez Date: Wed, 20 Oct 2010 23:07:04 +0000 (-0700) Subject: ath9k: add locking for starting the PCU on RX X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=7583c550c3e635dcc61ab127c36ecefd59fb8dc8;p=deliverable%2Flinux.git ath9k: add locking for starting the PCU on RX There was some locking for starting some parts of RX but not for starting the PCU. Include this otherwise we can content against stopping the PCU. This can potentially lead to races against different buffers on the PCU which can lead to to the DMA RX engine writing to buffers which are already freed. This is part of a series that will help resolve the bug: https://bugzilla.kernel.org/show_bug.cgi?id=14624 For more details about this issue refer to: http://marc.info/?l=linux-wireless&m=128629803703756&w=2 Cc: stable@kernel.org Cc: Ben Greear Cc: Kyungwan Nam Signed-off-by: Luis R. Rodriguez Tested-by: Ben Greear Signed-off-by: John W. Linville --- diff --git a/drivers/net/wireless/ath/ath9k/recv.c b/drivers/net/wireless/ath/ath9k/recv.c index e581b1f6c40c..b3c9baf855c4 100644 --- a/drivers/net/wireless/ath/ath9k/recv.c +++ b/drivers/net/wireless/ath/ath9k/recv.c @@ -297,11 +297,11 @@ static void ath_edma_start_recv(struct ath_softc *sc) ath_rx_addbuffer_edma(sc, ATH9K_RX_QUEUE_LP, sc->rx.rx_edma[ATH9K_RX_QUEUE_LP].rx_fifo_hwsize); - spin_unlock_bh(&sc->rx.rxbuflock); - ath_opmode_init(sc); ath9k_hw_startpcureceive(sc->sc_ah, (sc->sc_flags & SC_OP_OFFCHANNEL)); + + spin_unlock_bh(&sc->rx.rxbuflock); } static void ath_edma_stop_recv(struct ath_softc *sc) @@ -504,10 +504,11 @@ int ath_startrecv(struct ath_softc *sc) ath9k_hw_rxena(ah); start_recv: - spin_unlock_bh(&sc->rx.rxbuflock); ath_opmode_init(sc); ath9k_hw_startpcureceive(ah, (sc->sc_flags & SC_OP_OFFCHANNEL)); + spin_unlock_bh(&sc->rx.rxbuflock); + return 0; }