[vdr] DXR3 jams the whole system

[Jukka Tastula]

On Tuesday 19 April 2005 19:00, Sami Hakkarainen wrote:
> issues. If you have any suggestions, need more details, anything, this
> is a desperate man writing, please reply.

If the whole system hangs that means there's a problem with some driver in 
the kernel or the hardware, not vdr.  But then you say it still responds 
to ping so there's no telling if it's just some runaway program spawning 
processes as fast as it can making the system too busy (perhaps a good 
idea to set the sshd process to -20 priority to make sure it can always do 
what it needs to do) to respond before timeout or if some part of the 
kernel actually decided to stop working. 

"It just hangs" is not very much to go on but I guess the basic things to 
check are still worth mentioning, again.

First disable the ACPI and APIC (and MSI if you were crazy enough to 
compile it in) irq nonsense (ie boot with pci=noacpi noapic). Most (all?) 
distributions enable these two troublemakers by default. I honestly have 
no idea why. Then (after you disabled the acpi pci irq routing thing, very 
important) check for irq conflicts in lspci. Change cards around in the 
pci slots until you find a non-conflicting setup. Sure, they should 
happily share irqs but try tell that to my computers; they're not 
listening to the theory at all. Yours probably isn't either.

If you're using an AMD K7 cpu you probably want to disable athlon power 
saving with athcool in case your board (like both my boards (epox boards 
btw)) enables it by default. If you have this you've probably noticed it 
already. For me it causes constant dropouts in video and audio. Took a 
while to figure out what was going on. Sometimes the box just locks hard 
with this thing enabled. I didn't think it possible that some manufacturer 
would be stupid enough to enable this nonsense by default. Just leave it 
to epox, they'll manage to get it wrong.

Make sure you're using the latest em8300 from cvs. Disable NPTL if your 
system was compiled with it.   Try different kernel versions, not just 
different vdr versions.  Vanilla kernels are probably the best place to 
start testing. On my vdr box 2.6.9+cvs lirc+cvs em8300+cvs dvb-kernel 
appears to be a very stable combination. Anything above that and it's five 
days and the kernel decides to disable the dvb card's irq.

It would also be very interesting to see if there are any clues printed on 
the console or what kind of processes are running on the system when this 
"crash" occurs. You'll probably need a monitor and keyboard connected to 
the system to get this though.