From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mga09.intel.com ([134.134.136.24]:36580 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759894Ab2CWUeL (ORCPT ); Fri, 23 Mar 2012 16:34:11 -0400 Date: Fri, 23 Mar 2012 13:34:04 -0700 From: Sarah Sharp To: Larry Finger Cc: jerome huang , "Xu, Andiry" , linux-usb@vger.kernel.org, linux-wireless@vger.kernel.org Subject: Re: rt8192cu on USB3 Message-ID: <20120323203404.GD5207@xanatos> (sfid-20120323_213419_661440_4AB17FFA) References: <4F585BA9.6020903@amd.com> <2A76B9D36150BE4293842BC2FE8FF165016A31@SCYBEXDAG04.amd.com> <4F58F2D0.5060805@lwfinger.net> <4F59800B.80407@lwfinger.net> <20120322223107.GA8877@xanatos> <4F6BDEDF.2020907@lwfinger.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <4F6BDEDF.2020907@lwfinger.net> Sender: linux-wireless-owner@vger.kernel.org List-ID: On Thu, Mar 22, 2012 at 09:24:31PM -0500, Larry Finger wrote: > On 03/22/2012 05:31 PM, Sarah Sharp wrote: > > >Larry, if the driver doesn't cancel an URB that the device doesn't > >respond to, then it will just be left on the endpoint ring. If the > >driver then tries to queue new transfers to that same endpoint, but the > >device keeps NAKing the uncancelled transfer, then the endpoint ring > >would fill up with unanswered transfers. > > > >Perhaps some userspace or kernel portion is forgetting to cancel URBs > >before moving onto the next thing? You said you moved to asynchronous > >transfers, so maybe the problem lies there? > > The writes have always been asynchronous and reads are synchronous. > The only change was to convert the firmware uploading writes from > 32-bits at a time into block writes of 1000+ 32-bit words. Yeah, that's going to cause the out-of-room warning under xHCI. That should be fixed in the 3.4-rc1 kernel though. > Would xhci be worse that ohci or ehci in terms of the device not > responding to URBs? We only see problems with USB3.0 hubs, never > with 2.0 or 1.1. That's because EHCI handles arbitrarily large transfers, and xHCI didn't until now. > I am looking into changing the writes to be synchronous. That should > clear up any problems. Yeah, your problem probably was in the bulk large transfer, not the unfinished canceled URBs. I would suggest getting your reporters to just try 3.4-rc1 and see if it helps before doing too much work to debug this. Sarah Sharp