Re: error message for invalid mapping?

You can increase the verbosity of sigma0 by setting verbose to a value > 0
(i use 10 most times). The variable is in
pistachio/user/serv/sigma0/sigma0.cc.
You can enable tracepoints in the kernel debugger by pressing 'r' and then
enter the value of the tracepoint. 'E' enables all tracepoints. If you do
that i suggest you disable the TIME_SLICE_ENDED tracepoint because it kicks
in a lot and garbages the screen :).

-Bernhard

On 9/10/06, Joshua Haberman <[email protected]> wrote:
>
> I spent the last several days tracking down a bug in my code.  I was
> trying to make my pager send a MapItem in response to a page fault, but
> the mapping would never take effect.  The page fault would keep
> re-occuring.
>
> I finally figured out the problem: I was trying to send an fpage of memory
> that I hadn't requested from sigma0.  Since it was part of a "bootloader
> specific" region of memory, you have to explicitly request it from sigma0
> -- I couldn't just rely on page faults to obtain it.
>
> I was checking the success code from the IPC and I had turned on all
> tracepoints.  Neither indicated what the problem was.  Do you think that
> this error condition could either:
>
> 1. make the IPC fail
> 2. log a tracepoint message about the failure
>
> I would otherwise like to take this opportunity to propose a patch, but of
> all the code in the kernel, I don't think that modifying
> generic/linear_ptab_walker.cc is a good first project.  :)
>
> Thanks,
> Josh
>
>
>