On 2012-02-09 12:01 AM, Pavel Roskin wrote: > On Wed, 8 Feb 2012 14:44:54 -0500 > "John W. Linville" <linville@xxxxxxxxxxxxx> wrote: > >> On Wed, Feb 08, 2012 at 08:38:00PM +0100, Felix Fietkau wrote: >> > On 2012-02-08 8:25 PM, John W. Linville wrote: >> > > On Wed, Feb 08, 2012 at 07:17:11PM +0100, Felix Fietkau wrote: >> > >> Most rate control implementations assume .get_rate >> > >> and .tx_status are only called once the per-station data has >> > >> been fully initialized. minstrel_ht crashes if this assumption >> > >> is violated. >> > >> >> > >> Signed-off-by: Felix Fietkau <nbd@xxxxxxxxxxx> >> > >> Tested-by: Arend van Spriel <arend@xxxxxxxxxxxx> >> > >> --- >> > >> net/mac80211/rate.h | 2 +- >> > >> 1 files changed, 1 insertions(+), 1 deletions(-) >> > >> >> > >> diff --git a/net/mac80211/rate.h b/net/mac80211/rate.h >> > >> index 5fc3135..fbb1efd 100644 >> > >> --- a/net/mac80211/rate.h >> > >> +++ b/net/mac80211/rate.h >> > >> @@ -37,7 +37,7 @@ static inline void >> > >> rate_control_tx_status(struct ieee80211_local *local, struct >> > >> ieee80211_sta *ista = &sta->sta; void *priv_sta = >> > >> sta->rate_ctrl_priv; >> > >> - if (!ref) >> > >> + if (!ref || !test_sta_flag(sta, WLAN_STA_RATE_CONTROL)) >> > >> return; >> > >> >> > >> ref->ops->tx_status(ref->priv, sband, ista, priv_sta, >> > >> skb); >> > > >> > > Any reason not to apply this for 3.3? Or stable? >> > I think 3.3 doesn't have that sta flag, the issue was probably >> > introduced with the 3.4 changes. >> > I don't remember something like this appearing in earlier versions. >> >> Cool, thanks. > > I believe 3.3 is affected. At least it looks like the Fedora bug 768639 > (https://bugzilla.redhat.com/show_bug.cgi?id=768639) is caused by > calling .tx_status at a wrong time. Fedora kernels use > compat-wireless-3.3. I'm going to test the bleeding edge > compat-wireless with the patch by Felix to see if it fixes things. > > The lack of the WLAN_STA_RATE_CONTROL flag doesn't mean that the old > behavior was correct. The flag was introduced to correct that behavior. > > The oldest report is dated 2011-12-17 and it's about Linux 3.2.0-rc5 > with compat-wireless-2011-12-01. Only .get_rate and .tx_status are affected, wireless-testing commit e1936e9407138b483e6d1332dd944afec8131f30 adds one of the checks, and my commit adds the other. Maybe John could merge those two to 3.3. - Felix -- 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
