Re: [kvm-unit-tests PATCH v2 14/14] powerpc/ppc64: HACK: make a fake debug-exit

[Thomas Huth <thuth@redhat.com>]

On 08.02.2016 19:53, Andrew Jones wrote:
> We should use a QEMU debug-exit device like chr-testdev, but for
> now we just fake things by outputting the exit code (which we
> parse later) and quitting with RTAS (which always exits with zero).
> 
> (When we've got a real debug-exit working, then this patch can
>  be reverted.)
> 
> Signed-off-by: Andrew Jones <drjones@redhat.com>
> ---
>  lib/powerpc/io.c | 4 ++++
>  powerpc/run      | 7 +++++--
>  2 files changed, 9 insertions(+), 2 deletions(-)

Patch looks fine to me as an initial solution (and I'd also suggest to
remove the "HACK" in the title, as Paolo already said).

For a future improvement: Not sure, but there is a "ibm,os-term" RTAS
call which "[...] is provided for the OS to indicate to the platform
that it has terminated normal operation. A string of information is
passed to the platform", according to LoPAPR chapter 7.3.9.1. Maybe that
could be used to implement the debug-exit functionality? QEMU seems to
already send a GUEST_PANIC_ACTION_PAUSE event in this case, but the
parameter string is not taken into account yet...

 Thomas