On Fri, Jun 5, 2009 at 7:41 AM, Luis R. Rodriguez<lrodriguez@xxxxxxxxxxx> wrote: > Unfortunately locking the driver rate control private area > doesn't resolve this issue and in fact causes some issues. > The root cause is yet undetermined. For now instead of crashing > lets just downgrades the ASSERT() and only show a trace when > we are debugging with ATH_DBG_CONFIG enabled. That attempt > and its results can be seen here: > > http://marc.info/?l=linux-wireless&m=124399166108295&w=1 > > The ASSERT was happening because the rate control algorithm > figures it should find at least one valid dual stream or > single stream rate. *Something* is causing us to not find > such rate. This happens after association and only when HT > is enabled AFAICT. What we are doing by downgrading the assert > is informing the driver to use the lowest rate index. When > this happens lets disable multi rate retry and only try on > the lowest supported rate. > > Traces of the ASSERT are available on this thread: > > http://marc.info/?l=linux-wireless&m=124277331319024 > > At least one bug report (as side issue, mind you): > > https://bugzilla.redhat.com/show_bug.cgi?id=503285 > > Signed-off-by: Luis R. Rodriguez <lrodriguez@xxxxxxxxxxx> > --- > drivers/net/wireless/ath/ath9k/debug.h | 1 + > drivers/net/wireless/ath/ath9k/rc.c | 40 +++++++++++++++++++++++++++---- > 2 files changed, 35 insertions(+), 6 deletions(-) > > diff --git a/drivers/net/wireless/ath/ath9k/debug.h b/drivers/net/wireless/ath/ath9k/debug.h > index edda15b..9d72bc8 100644 > --- a/drivers/net/wireless/ath/ath9k/debug.h > +++ b/drivers/net/wireless/ath/ath9k/debug.h > @@ -30,6 +30,7 @@ enum ATH_DEBUG { > ATH_DBG_CONFIG = 0x00000200, > ATH_DBG_FATAL = 0x00000400, > ATH_DBG_PS = 0x00000800, > + ATH_DBG_RATE = 0x00001000, > ATH_DBG_ANY = 0xffffffff > }; > > diff --git a/drivers/net/wireless/ath/ath9k/rc.c b/drivers/net/wireless/ath/ath9k/rc.c > index ba06e78..abad86b 100644 > --- a/drivers/net/wireless/ath/ath9k/rc.c > +++ b/drivers/net/wireless/ath/ath9k/rc.c > @@ -741,10 +741,24 @@ static u8 ath_rc_ratefind_ht(struct ath_softc *sc, > if (rate > (ath_rc_priv->rate_table_size - 1)) > rate = ath_rc_priv->rate_table_size - 1; > > - ASSERT((rate_table->info[rate].valid && > - (ath_rc_priv->ht_cap & WLAN_RC_DS_FLAG)) || > - (rate_table->info[rate].valid_single_stream && > - !(ath_rc_priv->ht_cap & WLAN_RC_DS_FLAG))); > + if (rate_table->info[rate].valid && > + (ath_rc_priv->ht_cap & WLAN_RC_DS_FLAG)) > + return rate; > + > + if (rate_table->info[rate].valid_single_stream && > + !(ath_rc_priv->ht_cap & WLAN_RC_DS_FLAG)); > + return rate; > + > + /* > + * This should not happen, but we know it does for now... This > + * needs a proper fix but we're still not sure how this is caused. > + * Its not *critical* though so lets just warn when debug is enabled > + * for configuration changes. > + */ > + if (sc->debug.debug_mask & ATH_DBG_RATE) > + WARN_ON(1); WARN_ON(sc->debug.debug_mask & ATH_DBG_RATE) -- Vista: [V]iruses, [I]ntruders, [S]pyware, [T]rojans and [A]dware. :-) -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
