ath9k: remove support for the FIF_PROMISC_IN_BSS filter flag

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>
Cc: stable@kernel.org
Signed-off-by: John W. Linville <linville@tuxdriver.com>

diff --git a/drivers/net/wireless/ath/ath9k/recv.c b/drivers/net/wireless/ath/ath9k/recv.c
index cb559e345b865ebb8aba346a72a6dbefe89ac3b0..a9c3f4672aa0e12736a24c8ddb4e4c280d635d29 100644 (file)
--- a/drivers/net/wireless/ath/ath9k/recv.c
+++ b/drivers/net/wireless/ath/ath9k/recv.c
@@ -413,9 +413,7 @@ 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)