Re: [kvm-unit-tests PATCH 2/2] powerpc: restore TOC pointer

[Thomas Huth <thuth@redhat.com>]

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On 20.04.2016 07:59, David Gibson wrote:
> On Tue, 19 Apr 2016 19:26:28 +0200
> Laurent Vivier <lvivier@redhat.com> wrote:
> 
>> As the TOC pointer can be corrupted by the main program,
>> we must restore it in the exception handler.
>>
>> As we know where we are loaded, we can now compute it easily.
>>
>> To compute it only in the common part of the exception handler
>> (call_handler), store the address of call_handler at an absolute
>> address in memory to be able to call the handler from the exception
>> table (as SLOF does).
>>
>> Reported-by: Thomas Huth <thuth@redhat.com>
>> Signed-off-by: Laurent Vivier <lvivier@redhat.com>
> 
> So, this looks ok as long as the unit tests are built with a single
> TOC.

In case there would be multiple TOCs, the previous exception handler
would not work at all anymore, since it does not set up r2 at all.

So for the current scope of kvm-unit-tests, I think this here is already
enough - we can still extend it later in case we ever need to support
multiple TOCs. So to me, this patch looks fine:

Reviewed-by: Thomas Huth <thuth@redhat.com>



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