On Mon, 2009-01-19 at 13:37 +1000, Brendon Higgins wrote: > 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 drivers > > 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 accessing > > /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, now > > the device is accessible. > > > > So it seems something is wrong in the cx8802 module. Something is not being > > 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? Well, you have the clues actually; they're in your log files. At the time of the crash, what shows up in dmesg, /var/log/messages, and any log that VDR creates? Since modprobe after the crash failed with -ENODEV ["...cx88-dvb.ko): No such device], a quick grep through cx88-dvb.c in the source shows that that can only happen in a few places. It should be easy to spot in the logs. Adding an options cx88_dvb debug=1 line to /etc/modprobe.conf would make things easier to see in the logs as well. Also what is the source of your cx88 driver: Debian Testing or the v4l-dvb repo? > Or care? The issue is usually not one of caring, but one of having time, the specific hardware, and ability to reporduce the problem. Regards, Andy > I just noticed I posted > to the linux-dvb list which has been deprecated, so I'm quoting it here in > its entirety in case relevent people missed it. Is there anything else I can > do? > > Peace, > Brendon -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
