From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail.kapsi.fi ([217.30.184.167]:33134 "EHLO mail.kapsi.fi" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752844Ab2FCCos (ORCPT ); Sat, 2 Jun 2012 22:44:48 -0400 Received: from dyn3-82-128-188-130.psoas.suomi.net ([82.128.188.130] helo=localhost.localdomain) by mail.kapsi.fi with esmtpsa (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.72) (envelope-from ) id 1Sb0o9-0005g9-Gr for linux-media@vger.kernel.org; Sun, 03 Jun 2012 05:44:45 +0300 Message-ID: <4FCACF9C.8060509@iki.fi> Date: Sun, 03 Jun 2012 05:44:44 +0300 From: Antti Palosaari MIME-Version: 1.0 To: linux-media Subject: Re: Fwd: [Bug 827538] DVB USB device firmware requested in module_init() References: <4FC91D64.6090305@iki.fi> <4FCA41D7.2060206@iki.fi> In-Reply-To: <4FCA41D7.2060206@iki.fi> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-media-owner@vger.kernel.org List-ID: On 06/02/2012 07:39 PM, Antti Palosaari wrote: > On 06/01/2012 10:52 PM, Antti Palosaari wrote: >> >> >> -------- Original Message -------- >> Subject: [Bug 827538] DVB USB device firmware requested in module_init() >> Date: Fri, 01 Jun 2012 19:44:17 +0000 >> From: bugzilla@redhat.com >> To: crope@iki.fi >> >> https://bugzilla.redhat.com/show_bug.cgi?id=827538 >> >> Kay Sievers changed: >> >> What |Removed |Added >> ---------------------------------------------------------------------------- >> >> >> CC| |gansalmon@Gmail.com, >> | |itamar@ispbrasil.com.br, >> | |kernel-maint@redhat.com, >> | |madhu.chinakonda@gmail.com >> Component|udev |kernel >> Assignee|udev-maint@redhat.com |kernel-maint@redhat.com >> Summary|DVB USB device firmware |DVB USB device firmware >> |downloading takes 30 |requested in module_init() >> |seconds | >> >> --- Comment #1 from Kay Sievers --- >> This is very likely a kernel driver issue. >> >> Drivers must not load firmware in the module_init() path, or device >> probe()/bind() path. This creates a deadlock in the event handling. >> >> We used to silently try to work around that, but recently started >> to log this error explicitely. >> >> The firmware should in general be requested asynchronously, or at the >> first >> open() of the device. >> >> Details are here: >> http://thread.gmane.org/gmane.linux.network/217729 >> > > I suspect all of our DVB USB firmere downloading problems are coming > from that issues. I mean especially those suspend / resume failings too. > > What I think I will try to delay driver registertration using workqueue. > Return just success for the USB driver probe and continue real probe > from workqueue. That solves DVB USB firmware loading problems. I wonder why that udev requirement not to block module init was not informed for linux-media... Now it is much work to look thru all drivers and check those did not load firmware on attach or init. regards Antti -- http://palosaari.fi/