Nova-T, cx88-dvb & "cx88_wakeup: 2 buffers handled (should be 1)"

[Hanno Zulla <abos@hanno.de>]

Hi,

[ please cc me with replies. ]

I have asked this upstream at linux-dvb [1] and to the Ubuntu kernel's
bugtracker [2], but no help so far. Googling around, one can find other
reports about this, but no solution, either.


Using a Nova-T dvb card, I get the following in /var/log/messages...

22:09:54 kernel: cx88_wakeup: 2 buffers handled (should be 1)
22:09:57 kernel: cx88_wakeup: 2 buffers handled (should be 1)
22:10:06 kernel: cx88_wakeup: 2 buffers handled (should be 1)
22:10:09 kernel: cx88_wakeup: 2 buffers handled (should be 1)
22:10:12 kernel: cx88_wakeup: 2 buffers handled (should be 1)
22:10:15 kernel: cx88_wakeup: 2 buffers handled (should be 1)

...every few seconds while watching TV with xine or other dvb-apps. The
event results in a visible interruption of the video stream.


Looking on the net for solutions, I tried these:

- changing pci latency in the bios settings

- putting the card into a different pci slot

- using "pci=routeirq" or "pci=noacpi" kernel boot parameters

NONE of these solved the problem.

Please see [2] for more info.


The problem appears with three different recent Linux distribution
kernels: Ubuntu 2.6.22-7-generic, Ubuntu 2.6.20-15-generic, Suse
2.6.18.2-34-default.

The problem is not hardware-specific, it appears with an Intel CPU and
Intel chipset as well as with an AMD CPU and a VIA chipset.

The problem appears to be shared irq resources [3]. However, my
mainboard doesn't allow to choose specific irqs for pci slots and
anyway, shared irqs shouldn't break this dvb card, in the first place.


What else can I try?


Thanks for any help,

Hanno


[1]
http://www.linuxtv.org/pipermail/linux-dvb/2007-May/018232.html
http://www.linuxtv.org/pipermail/linux-dvb/2007-July/018881.html

[2]
https://bugs.launchpad.net/ubuntu/+source/linux-source-2.6.20/+bug/119115

[3]
http://launchpadlibrarian.net/8036103/lspci-vvnn.log
http://launchpadlibrarian.net/8283449/lspci-vv.log