16.05 custom kernel call fails to get session capability.

[Norman Feske]

Hello Bob,

> [init -> ctrl_module] Uncaught exception of type
> 'Genode::Parent::Service_denied'
> [init -> ctrl_module] Warning: abort called - thread:
> ep                        
...
> The uncaught exception is being generated in my "pinmux_session"
> connection code when a capability for a session is requested, as shown
> the following in the following code snippet from pinmux_connection.h

I think you are observing a rather indirect symptom. The actual problem
is that the 'ctrl_module' aborted for some reason. E.g., it requested a
service for which no route is configured and got the 'Service_denied'
exception you see in the log. After aborting, the 'ctrl_module' exits.
Now, when the '437x_platform_client' tries open a session to this
service, it is no longer there. So init responds to the session request
with another 'Service_denied' exception. This is the one that you
observed in the 'Pinmux_connection' constructor.

You need to find out which kind of session 'ctrl_module' tried to open
when it aborted. I would instrument the code at
base/src/lib/base/child.cc like in the attached patch. With the patch
applied, you will see a nice log of session requests. Look for the one
that appears immediately before the 'ctrl_module' aborts. It might be
helpful to also print the session 'args'.

Cheers
Norman

-- 
Dr.-Ing. Norman Feske
Genode Labs

http://www.genode-labs.com · http://genode.org

Genode Labs GmbH · Amtsgericht Dresden · HRB 28424 · Sitz Dresden
Geschäftsführer: Dr.-Ing. Norman Feske, Christian Helmuth
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