Re: [PATCH v2] 802.11n IBSS: wlan0 stops receiving packets due to aggregation after sender reboot

From: Koen Vandeputte
Date: Tue Oct 29 2019 - 05:47:12 EST



On 29.10.19 10:03, Johannes Berg wrote:
On Tue, 2019-10-29 at 09:41 +0100, Koen Vandeputte wrote:

I can confirm the issue as I'm also seeing this sometimes in the field here.

Sometimes when a devices goes out of range and then re-enters,
the link refuses to "come up", as in rx looks to be "stuck" without any
reports in system log or locking issues (lockdep enabled)
Right. I've recently debugged this due to issues in distributed
beaconing (rather than moving in/out of range), but I guess it would be
relatively simple to reproduce this with wmediumd, if that can be
controlled dynamically?

What kernel are you running? You could check if you have

95697f9907bf ("mac80211: accept deauth frames in IBSS mode")
4b08d1b6a994 ("mac80211: IBSS: send deauth when expiring inactive STAs")

which might help somewhat, but don't fully cover the case of moving out
of range.

johannes

I'm running OpenWrt (kernel 4.14.150 with 4.19.79 mac80211)
I noticed these fixes last week and made a build 2 days ago with them backported to it.
Running in the field on roughly 4 devices since a day.

Koen