ath9k: remove support for the FIF_PROMISC_IN_BSS filter flag

commit 2e286947f1294239527c11f9f466ddce6466455b upstream.

The hardware rx filter flag triggered by FIF_PROMISC_IN_BSS is overly broad
and covers even frames with PHY errors. When this flag is enabled, this message
shows up frequently during scanning or hardware resets:

ath: Could not stop RX, we could be confusing the DMA engine when we start RX up

Since promiscuous mode is usually not particularly useful, yet enabled by
default by bridging (either used normally in 4-addr mode, or with hacks
for various virtualization software), we should sacrifice it for better
reliability during normal operation.

This patch leaves it enabled if there are active monitor mode interfaces, since
it's very useful for debugging.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/net/wireless/ath/ath9k/recv.c b/drivers/net/wireless/ath/ath9k/recv.c
index b2497b8601e5bb6e4f5411968d2bc5faedac8eb7..3867a2e8de39c92b1bc1fac7150506290d649e6c 100644 (file)
--- a/drivers/net/wireless/ath/ath9k/recv.c
+++ b/drivers/net/wireless/ath/ath9k/recv.c
@@ -439,9 +439,7 @@ u32 ath_calcrxfilter(struct ath_softc *sc)
         * mode interface or when in monitor mode. AP mode does not need this
         * since it receives all in-BSS frames anyway.
         */
-       if (((sc->sc_ah->opmode != NL80211_IFTYPE_AP) &&
-            (sc->rx.rxfilter & FIF_PROMISC_IN_BSS)) ||
-           (sc->sc_ah->is_monitoring))
+       if (sc->sc_ah->is_monitoring)
                rfilt |= ATH9K_RX_FILTER_PROM;
 
        if (sc->rx.rxfilter & FIF_CONTROL)