RFC/Patch more xmon additions

[Paul Mackerras]

will schmidt writes:

> Am looking for comments on this additional function i've added to xmon 
> on the side..
> 
> the bulk of my intent was to make it easier for me to poke at memory 
> within a particular user process.

The main problem I have with it is that we seem to be accessing a lot
of kernel data structures without checking any pointers or using
mread() to read the memory safely.  One of the goals of xmon is that
it should be as reliable as possible even if kernel data structures
are corrupted, and I think your patch would reduce that reliability.

Also, I'm not sure that there is any point doing a spin_trylock(),
since all cpus are supposed to be in xmon by the time you get to a
command prompt.  By all means bail out if spin_is_locked() returns
true, but I don't see the need to actually take the lock.

Regards,
Paul.