[Skiboot] [PATCH 0/4] next round of OPAL debugging improvements

[Stewart Smith]

Nicholas Piggin <npiggin at gmail.com> writes:
> The r13 clobber bug has been fixed in Linux upstream now, the next
> bit is the skiboot stack corruption caused by re-entry from the OS.
>
> Patches 1-3 have been posted here before in various RFCs. They give
> nicer back traces, make quiescing a bit more robust, and stop the
> stack from being destroyed, and make quiescing a bit more robust.
>
> Patch 4 is one I've found useful when testing with sreset injection
> into various parts of skiboot code.
>
> We can in general interrupt and resume OPAL after this series.
> Many specific cases are unlikely to work for other reasons, but
> we have a cut down sub-set of OPAL API that we allow through, so
> the task of making those reasonably robust should be manageable.

Neat.

I haven't hammered the series with sreset and fun like that, but we
should probably add something along those lines to op-test (hit it a lot
more when we had more bugs :)

When I build with STACK_CHECK=1, it seems that we never get below 10k of
free stack, but I'm not quite bold enough to suggest "8k is enough for
everyone", and just eating the extra memory for stacks is probably okay.

Series merged to master as of 87f55507195a166fb12ed1240ed3221964f11f40
-- 
Stewart Smith
OPAL Architect, IBM.