Re: [PATCH] [media] dvb-core: preserve the delivery system at cache clear

[Jim Darby <uberscubajim@gmail.com>]

Thanks for the patch Mauro. According to Gianluca that solves the 
backwards compatibility issue. This is great news.

In other news I've tried a few experiments. Firstly I tried using a 
3.2.0 unmodified straight out of the box kernel on my Core 2 64-bit 
system. I was unable to produce any faults. This would tend to lead one 
to suspect that it's a 32-bit problem or that my 32-bit machine is a bit 
flaky or slow.

So, as I wanted to try the new alpha 3 for Mageia 2 (a Mandriva fork) 
out and it has a 3.0 kernel that seemed to be a good idea. The bad news 
is that I'd run out of hardware. So I thought I'd be clever and run it 
as a virtual machine on my Core 2 system.

The good news is that it correctly recognised the stick and it seemed to 
work for standard definition. However, after setting it to record some 
HDTV programmes it failed. More importantly it failed in the same way as 
the 32-bit system.

This makes me think it's some kind of timing problem. The USB 
passthrough of VirtualBox may well not operate at the performance 
required for HDTV. Also by this time I'd put the stick on a USB 
extension lead which may have adversely affected the power feed.

For my next series of tests I plan to run it again on bare hardware. I'm 
going to try and use my older Core 2 machine which should have the CPU 
and electrical power.

None of which explains why it works on the 32-bit Athlon XP 2200+ when 
it's running 3.0.0 though. And has done so reliably for some time. Maybe 
some other things are happening in the kernel that much up the device 
timing or something.

Anyway, I'll keep people posted as to the progression of the testing.

Best regards,

Jim.