[pvrusb2] HVR-1950 driver loading problem

[Mike Isely]

On Tue, 16 Jun 2009, JE Geiger wrote:

> OK.  I have tried dropping down in kernel versions (2.6.26.8) (2.6.27.24) on
> same Fedora 11 and still the same problem.  So must be something not
> necessarily kernel related (repeating resets, not the Oops).
> 
> I enabled debug messages from udev and, although I know very little about
> udev, I get the general concept and if you search for the word firmware, you
> see it loaded then immediately later removed.  It sure looks like a udev
> problem for the repeating reset.  Would welcome a comment.  My udev is 141.
> 
> The udev log is http://www.kd4ab.org/udevdbug

Wish I could suggest something here, but right now I'm still at a loss.  
if ANYONE else is seeing this that would at least rule out your specific 
environment / hardware combination.


> 
> As far as the crash on PVR2_TRACE_STATE, I don't know.
> 
> Where is the function scnprintf defined and where is the object code.  I
> looked around and it is not one I recognize from my distant past (K&R 2nd,
> little white paperback).  Is this one of the "special" kernel functions.  I
> found google references to why it is used, etc. but I cannot find the actual
> function .h or .c.

The function scnprintf() is one of a bunch of kernel-resident printf 
variants.  It is defined within the kernel.  Given what you've described 
so far it's very plausible that a bad pointer is being passed as one of 
the parameters to this function, especially since turning on 
PVR2_TRACE_STATE - like the other debug bits - enables a bunch of 
otherwise dormant calls of this nature.  If you can pin down the file 
and line number where the bad call is being made then I can probably 
solve it.  But from the traceback you posted I didn't see enough there 
to pin that down (or I could have just not been awake - also entirely 
plausible...).


> 
> I have several machines and I will change the PC to another one and try
> again using a clean pvrusb2 as released with the kernel for Fedora 11.
> 
> Thanks for running the tests and the info about the trace bits being
> independent.   I will advise as I get further into this.  I think it makes
> more sense for me to test further as opposed to you using up your time.  I
> will ask questions if I get stuck.

Sure, sounds great.

  -Mike

-- 

Mike Isely
isely @ isely (dot) net
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