From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mx1.redhat.com ([209.132.183.28]:23760 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753901AbZKHQNH (ORCPT ); Sun, 8 Nov 2009 11:13:07 -0500 Message-ID: <4AF6EF59.90206@redhat.com> Date: Sun, 08 Nov 2009 17:18:33 +0100 From: Hans de Goede MIME-Version: 1.0 To: =?ISO-8859-2?Q?N=E9meth_M=E1rton?= CC: Jean-Francois Moine , V4L Mailing List Subject: Re: pac7302: INFO: possible circular locking dependency detected References: <4AF48F80.4000809@freemail.hu> <4AF68BC6.4040801@redhat.com> <4AF695CC.7040809@freemail.hu> In-Reply-To: <4AF695CC.7040809@freemail.hu> Content-Type: text/plain; charset=ISO-8859-2; format=flowed Content-Transfer-Encoding: 8bit Sender: linux-media-owner@vger.kernel.org List-ID: Hi, On 11/08/2009 10:56 AM, Németh Márton wrote: > Hi, > > Hans de Goede wrote: >> [snip] >> >> About the usb control msg errors, I don't think they are related to this issue at all, no real >> world app ever does a streamon and an mmap at the same time. As said if we could serialize mmap and >> ioctl at a high enough level, things would be fine too. > > I am using http://moinejf.free.fr/svv.c . In the start_capturing() function it calls the > VIDIOC_STREAMON ioctl in case of memory mapped mode. Is this wrong? Or do you mean under > "at the same time" that VIDIOC_STREAMON and mmap() is called from different tasks/threads? > Yes from 2 different threads, which are both the stream owner (so operating on the same FD). Regards, Hans