Date: Thu, 31 Jan 2013 00:14:25 +0000 (UTC) From: Adrian Chadd <adrian@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r246141 - head/sys/dev/ath Message-ID: <201301310014.r0V0EP04046963@svn.freebsd.org>
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Author: adrian Date: Thu Jan 31 00:14:25 2013 New Revision: 246141 URL: http://svnweb.freebsd.org/changeset/base/246141 Log: Work around some rather unfortunate race conditions inside net80211. Right now, ic_curchan seems to be updated rather quickly (ie, during the ioctl) and before the driver gets notified of what's going on. So what I was seeing was: * NIC was in channel X; * It generates PHY errors for channel X; * an ioctl comes along from userland and changes things to channel Y; * .. this updates ic_curchan, but hasn't yet reset the hardware; * in parallel, RX is occuring and it looks at ic_curchan; * .. which is channel Y, so events get stamped with that now. Sigh. Modified: head/sys/dev/ath/if_ath_rx.c Modified: head/sys/dev/ath/if_ath_rx.c ============================================================================== --- head/sys/dev/ath/if_ath_rx.c Thu Jan 31 00:02:49 2013 (r246140) +++ head/sys/dev/ath/if_ath_rx.c Thu Jan 31 00:14:25 2013 (r246141) @@ -431,18 +431,16 @@ ath_rx_tap(struct ifnet *ifp, struct mbu #ifdef AH_SUPPORT_AR5416 sc->sc_rx_th.wr_chan_flags &= ~CHAN_HT; if (rs->rs_status & HAL_RXERR_PHY) { - struct ieee80211com *ic = ifp->if_l2com; - /* * PHY error - make sure the channel flags * reflect the actual channel configuration, * not the received frame. */ - if (IEEE80211_IS_CHAN_HT40U(ic->ic_curchan)) + if (IEEE80211_IS_CHAN_HT40U(sc->sc_curchan)) sc->sc_rx_th.wr_chan_flags |= CHAN_HT40U; - else if (IEEE80211_IS_CHAN_HT40D(ic->ic_curchan)) + else if (IEEE80211_IS_CHAN_HT40D(sc->sc_curchan)) sc->sc_rx_th.wr_chan_flags |= CHAN_HT40D; - else if (IEEE80211_IS_CHAN_HT20(ic->ic_curchan)) + else if (IEEE80211_IS_CHAN_HT20(sc->sc_curchan)) sc->sc_rx_th.wr_chan_flags |= CHAN_HT20; } else if (sc->sc_rx_th.wr_rate & IEEE80211_RATE_MCS) { /* HT rate */ struct ieee80211com *ic = ifp->if_l2com;
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