From 7583c550c3e635dcc61ab127c36ecefd59fb8dc8 Mon Sep 17 00:00:00 2001 From: "Luis R. Rodriguez" <lrodriguez@atheros.com> Date: Wed, 20 Oct 2010 16:07:04 -0700 Subject: [PATCH] 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 <greearb@candelatech.com> Cc: Kyungwan Nam <kyungwan.nam@atheros.com> Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com> Tested-by: Ben Greear <greearb@candelatech.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> --- drivers/net/wireless/ath/ath9k/recv.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/drivers/net/wireless/ath/ath9k/recv.c b/drivers/net/wireless/ath/ath9k/recv.c index e581b1f6c40c93..b3c9baf855c49b 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; } -- GitLab