Re: [Qemu-devel] TCG problem with cpu_{st,ld}x_data ?

[Benjamin Herrenschmidt <benh@kernel.crashing.org>]

On Mon, 2016-07-25 at 19:30 +0530, Richard Henderson wrote:
> > Or can they also be called outside of that context ?
> 
> No, not without a valid return address.
> 
> E.g. it's not valid to have one helper call another, and for the second helper 
> use GETPC.  For this, typically, one must factor out a common function which 
> accepts a "retaddr" argument, which the callers must fill in with GETPC.

Right, I've figured that out. I notice that the cpu_ldl_code() are
sprinkled in parts that are "chancy".

For example we have one in powerpc_excp() to read the faulting
instruction, though that *should* never fail it's till not great.

I haven't completely figured out what code path instruction translation
faults take, I assume we longjmp out of the translation loop the same
was as we do out of the execution loop ?

Note: I've started cleaning that on ppc (but not fixing the -2 bug yet)
in there: very much a work in progress but I'd be happy to have initial
feedback (ignore patch 1 about MOL OSI, it's unrelated):

https://github.com/ozbenh/qemu/commits/wip

Cheers,
Ben.