[Skiboot] [PATCH] cpu: Cleanup AMR and IAMR when re-initializing CPUs

[Stewart Smith]

Benjamin Herrenschmidt <benh at kernel.crashing.org> writes:
> There's a bug in current Linux kernels leaving crap in those registers
> accross kexec and not sanitizing them on boot. This breaks kexec under
> some circumstances (such as booting a hash kernel from a radix one
> on P9 DD2.0).
>
> The long term fix is in Linux, but this workaround is a reasonable
> way of "sanitizing" those SPRs when Linux calls opal_reinit_cpus()
> and shouldn't have adverse effects.
>
> We could also use that same mechanism to cleanup other things as
> well such as restoring some other SPRs to their default value in
> the future.
>
> Signed-off-by: Benjamin Herrenschmidt <benh at kernel.crashing.org>

Merged to master (and 5.7-rc1) as of d98c46b55801015a887fa27752db421280a48f7b
-- 
Stewart Smith
OPAL Architect, IBM.