From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from rv-out-0506.google.com ([209.85.198.229]:25415 "EHLO rv-out-0506.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752895AbZASDhU (ORCPT ); Sun, 18 Jan 2009 22:37:20 -0500 Received: by rv-out-0506.google.com with SMTP id k40so2431993rvb.1 for ; Sun, 18 Jan 2009 19:37:19 -0800 (PST) From: Brendon Higgins To: linux-media@vger.kernel.org Subject: Regression since 2.6.25 kernel: Crash of userspace program leaves DVB device unusable Date: Mon, 19 Jan 2009 13:37:26 +1000 References: <200901031200.56314.blhiggins@gmail.com> In-Reply-To: <200901031200.56314.blhiggins@gmail.com> MIME-Version: 1.0 Content-Type: multipart/signed; boundary="nextPart1843588.5EXkndx9Al"; protocol="application/pgp-signature"; micalg=pgp-sha1 Content-Transfer-Encoding: 7bit Message-Id: <200901191337.31272.blhiggins@gmail.com> Sender: linux-media-owner@vger.kernel.org List-ID: --nextPart1843588.5EXkndx9Al Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Content-Disposition: inline Hi, I wrote to linux-dvb (2009-01-03 12:00 pm): > I've been coming up against a problem that seems to be with the DVB drive= rs > that occurs when a program using them, usually VDR in my case, terminates > uncleanly (segfault, general protection fault). Linux 2.6.25 doesn't have > this problem, but 2.6.26, 2.6.27, and 2.6.28 do, though 2.6.28 manifests > slightly differently to the others. I'll focus on what 2.6.28 does. I have > a DViCO FusionHDTV DVB-T Plus, running on an amd64 Debian Testing (mostly) > dual-core machine. > > After VDR crashes it attemps to restart itself. This was fine on 2.6.25, > but on later kernels the crash seems to leave the device in some unusable > state, where no program can subsequently use it - the device files > (/dev/dvb) no longer exist. (In 2.6.2[67], the files existed, but accessi= ng > /dev/dvb/adapter0/dvr0 resulted in "No such device".) I had figured out > that in order to get the device working again it is necessary to "rmmod > cx88_dvb cx8802; modprobe cx88_dvb". This worked in 2.6.2[67] without > trouble, but in 2.6.28, it's as if the cx88_dvb module gets lost somehow. > It doesn't appear in lsmod, however: > phi:~# modprobe cx88_dvb > FATAL: Error inserting cx88_dvb > (/lib/modules/2.6.28/kernel/drivers/media/video/cx88/cx88-dvb.ko): No such > device > phi:~# rmmod cx88_dvb cx8802 > ERROR: Module cx88_dvb does not exist in /proc/modules > phi:~# modprobe cx88_dvb > > Note that probing it works only *after* cx8802 was unloaded. As before, n= ow > the device is accessible. > > So it seems something is wrong in the cx8802 module. Something is not bei= ng > cleaned up after a userspace program crashes while using it, leaving the > DVB system in a broken state. > > I'd very much like this to not be the case, since on my system a VDR crash > is somewhat inevitable, and the automatic restart *was* very handy, back = in > 2.6.25. Deafening silence. Does nobody have a clue? Or care? I just noticed I poste= d=20 to the linux-dvb list which has been deprecated, so I'm quoting it here in= =20 its entirety in case relevent people missed it. Is there anything else I ca= n=20 do? Peace, Brendon --nextPart1843588.5EXkndx9Al Content-Type: application/pgp-signature; name=signature.asc Content-Description: This is a digitally signed message part. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (GNU/Linux) iEYEABECAAYFAklz9XYACgkQCTfPD0Uw3q8WlwCfZrzWDYBiT75VdrS/ViQDg2i4 AhcAnRZNxtqhzwWi8T8wNqzkSQwkYATE =JgnE -----END PGP SIGNATURE----- --nextPart1843588.5EXkndx9Al--