Re: Compat-wireless-3.2-rc6-3 is broken for rt2860 device

Helmut Schaa schrieb:

Hi,

Am Mittwoch, 4. Januar 2012, 09:38:02 schrieb Andreas Hartmann:

quoted

Helmut Schaa schrieb:

quoted

quoted

Removing this patch

mac80211: retry sending failed BAR frames later instead of tearing down
aggr (http://www.spinics.net/lists/linux-wireless/msg76379.html) makes
it working again.

Device is: RaLink RT2800 802.11n PCI

What's the client device connected to the rt2x00 AP?

It's a rt3572 usb chip (Linksys WUSB600N v2), driven with the rt3572sta
module.

quoted

Mind to send a
802.11 capture wen this stall happens?

Andreas provided me with a capture now. The interesting part is that
the rt2x00 AP sends bursts of BARs with the same sequence number when
the stall happens. I only had a quick look at the code in question but
couldn't see anything wrong at a first glance.

Some additional information:

- The AP initiates BARs for 6 different, successive sequence numbers.
- The first 5 sequence numbers are finished after sending of about 8 (!)
BAR's.
Important: each BAR is responded *instantly* by the STA.
- The BAR for the next sequence number is sent "endless" though the STA
responses to each BAR instantly again.


Another thing: it is striking, that the performance from STA -> AP is at
max 8,5 MBit/s, whereas the performance from AP -> STA can be 15 MBit/s
(all measured with netperf).


Could it be, that somewhere in the stack of the AP the response packet
from STA -> AP get's lost or ignored or blocked?



Kind regards,
Andreas