2021-03-30 23:25:01

by Ben Greear

Subject: Question on "mac80211: HE STA disassoc due to QOS NULL not sent"

While debugging a station polling issue. Should it maybe send
a probe request instead of just not probing at all?

commit f39b07fdfb688724fedabf5507e15eaf398f2500
Author: Shay Bar <[email protected]>
Date: Wed Jul 3 16:18:48 2019 +0300

mac80211: HE STA disassoc due to QOS NULL not sent

In case of HE AP-STA link, ieee80211_send_nullfunc() will not
send the QOS NULL packet to check if AP is still associated.

In this case, probe_send_count will be non-zero and
ieee80211_sta_work() will later disassociate the AP, even
though no packet was ever sent.

Fix this by decrementing probe_send_count and not calling
ieee80211_send_nullfunc() in case of HE link, so that we
still wait for some time for the AP beacon to reappear and
don't disconnect right away.

Signed-off-by: Shay Bar <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
[clarify commit message]
Signed-off-by: Johannes Berg <[email protected]>

diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index 225633d9e2d4bd..e89ed800f01259 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -2512,7 +2512,10 @@ static void ieee80211_mgd_probe_ap_send(struct ieee80211_sub_if_data *sdata)

if (ieee80211_hw_check(&sdata->local->hw, REPORTS_TX_ACK_STATUS)) {
ifmgd->nullfunc_failed = false;
- ieee80211_send_nullfunc(sdata->local, sdata, false);
+ if (!(ifmgd->flags & IEEE80211_STA_DISABLE_HE))
+ ifmgd->probe_send_count--;
+ else
+ ieee80211_send_nullfunc(sdata->local, sdata, false);
} else {
int ssid_len;


Thanks,
Ben

--
Ben Greear <[email protected]>
Candela Technologies Inc http://www.candelatech.com

2021-04-08 12:58:17

by Johannes Berg

Subject: Re: Question on "mac80211: HE STA disassoc due to QOS NULL not sent"

On Tue, 2021-03-30 at 16:23 -0700, Ben Greear wrote:
> While debugging a station polling issue. Should it maybe send
> a probe request instead of just not probing at all?
>
> commit f39b07fdfb688724fedabf5507e15eaf398f2500
> Author: Shay Bar <[email protected]>
> Date: Wed Jul 3 16:18:48 2019 +0300
>
>      mac80211: HE STA disassoc due to QOS NULL not sent
>
>      In case of HE AP-STA link, ieee80211_send_nullfunc() will not
>      send the QOS NULL packet to check if AP is still associated.

Quite possibly we should just fix this - I think there was a recent
discussion on that here on the list?

johannes