Return-path: Received: from p15195424.pureserver.info ([82.165.34.74]:59583 "EHLO p15195424.pureserver.info" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755700Ab3IIXqO (ORCPT ); Mon, 9 Sep 2013 19:46:14 -0400 Message-ID: <522E5D83.9060103@ilande.co.uk> (sfid-20130910_014617_621306_7048EB35) Date: Tue, 10 Sep 2013 00:45:07 +0100 From: Mark Cave-Ayland MIME-Version: 1.0 To: Larry Finger CC: Timothy Rundle , linux-wireless References: <522D054B.5060205@lwfinger.net> <522DD856.7050309@ilande.co.uk> <522DE1BE.6070904@lwfinger.net> <522DE8CA.9010008@ilande.co.uk> <522DFF83.6000605@lwfinger.net> <522E0573.4000804@ilande.co.uk> <522E1B7D.5010107@lwfinger.net> <522E463E.4040701@ilande.co.uk> <522E5416.4010901@lwfinger.net> In-Reply-To: <522E5416.4010901@lwfinger.net> Subject: Re: RTL8192CU continually reconnecting Content-Type: text/plain; charset=UTF-8; format=flowed Sender: linux-wireless-owner@vger.kernel.org List-ID: On 10/09/13 00:04, Larry Finger wrote: >> I also tried another experiment which was to change your patch so that >> instead >> of logging just the first 100 beacons to dmesg, log every 10th beacon >> (count % >> 10) to dmesg instead. This showed that even when the timeouts are >> occurring >> against the AP, I'm still seeing a continual stream of beacons from other >> stations on the network. > > Looking at only every 10th one could be systematically missing the ones > from your AP. Oh sure - what I was looking to prove was whether it was all beacons that weren't getting through, or just the ones from the AP when the timeout occurred. >> This makes me wonder if Oleksij is correct in that the problem is that >> not all >> the frames coming from the USB interface are being picked up by the >> driver. >> Perhaps not all incoming USB RX buffers are being scanned (causing >> some queued >> frames to be lost) or maybe USB transfers can contain more than 1 >> frame and >> rtlwifi is only catching the first frame within each notified transfer? > > None of those suppositions make any sense. Well I freely admit that I don't have much knowledge of the kernel USB layers (only from some old embedded systems years ago), so it was really just a case of thinking out loud... >> To double check whether it was a general ehci-pci problem, I tried >> plugging in a >> spare zd1211rw dongle and that worked absolutely fine. So I think >> that's a >> reasonable indication that general USB function is okay. > > I do not suspect any USB problem unless it is in rtl8192cu. Okay. > Could you please run the attached patch? It will only print messages for > your AP, and print enough to still be getting them when the AP timeout > occurs. Done. dmesg output: http://www.ilande.co.uk/tmp/rtl8192cu_patch-3-dmesg.txt wpa_supplicant output: http://www.ilande.co.uk/tmp/rtl8192cu_patch-3-wpa_supplicant.txt Now the interesting part was as you can see from the logs, I managed to get a reasonably long association to the AP towards the end so I tried running dhclient against the wlan1 interface - this was slow, taking about 60s to complete, but it did eventually return with an IP address. With that in place, I tried pinging 8.8.8.8 and ended up with a very poor connection, with the ping exit banner reporting 87% packet loss :( ATB, Mark.