From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from galahad.ideasonboard.com ([185.26.127.97]:37344 "EHLO galahad.ideasonboard.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752432AbbCJHCx convert rfc822-to-8bit (ORCPT ); Tue, 10 Mar 2015 03:02:53 -0400 From: Laurent Pinchart To: =?ISO-8859-1?Q?Bj=F8rn?= Mork Cc: linux-media@vger.kernel.org, Hans Verkuil Subject: Re: [PATCH] uvcvideo: Don't call vb2 mmap and get_unmapped_area with queue lock held Date: Tue, 10 Mar 2015 01:52:02 +0200 Message-ID: <8389917.WAzPk9jDDo@avalon> In-Reply-To: <871tkye8g3.fsf@nemi.mork.no> References: <1424111134-22413-1-git-send-email-laurent.pinchart@ideasonboard.com> <87k2z9558i.fsf@nemi.mork.no> <871tkye8g3.fsf@nemi.mork.no> MIME-Version: 1.0 Content-Transfer-Encoding: 8BIT Content-Type: text/plain; charset="iso-8859-1" Sender: linux-media-owner@vger.kernel.org List-ID: Hi Bjørn, (it took me half an hour to figure out how to write ø on my keyboard :-)) On Monday 09 March 2015 12:06:36 Bjørn Mork wrote: > Bjørn Mork writes: > > Laurent Pinchart writes: > >> Bjørn, does this fix the circular locking dependency you have reported in > >> "[v3.19-rc7] possible circular locking dependency in uvc_queue_streamoff" > >> ? The report mentions involves locks, so I'm not 100% this patch will fix > >> the issue. > > > > Sorry, I forgot all about that report after firing it off... Should > > have followed it up with some more details. > > > > Grepping my logs now I cannot find this warning at all after the one I > > reported. I see it once before (while running 3.19-rc6). So it is > > definitely not easily reproducible. And I have a bad feeling the > > trigger might involve completely unrelated USB issues... > > > > In any case, thanks for the patch. I will test it for a while and let > > you know if the same warning shows ut with it. But based on the rare > > occurence, I don't think I ever will be able to positively confirm that > > the warning is gone. > > FWIW, I have not seen the warning after applying this patch, so it > appears to fix the problem. Thanks. You're welcome. > If I'm wrong, then I'm sure Murphy will tell us as soon as I send this > email :-) I'd be happy to prove Murphy wrong for once. -- Regards, Laurent Pinchart