Current POWER cpus allow for a VRMA, a special mapping which describes a
guest's view of memory when in real mode (MMU off, from the guest's point
of view). Older cpus didn't have that which meant that to support a guest
a special host-contiguous region of memory was needed to give the guest its
Real Mode Area (RMA).
KVM used to provide special calls to allocate a contiguous RMA for those
cases. This was useful in the early days of KVM on Power to allow it to be
tested on PowerPC 970 chips as used in Macintosh G5 machines. Now, those
machines are so old as to be almost irrelevant.
The normal qemu deprecation process would require this to be marked
deprecated then removed in 2 releases. However, this can only be used
with corresponding support in the host kernel - which was dropped
years ago (in c17b98cf "KVM: PPC: Book3S HV: Remove code for PPC970
processors" of 2014-12-03 to be precise). Therefore it should be ok
to drop this immediately.
Just to be clear this only affects *KVM HV* guests with PowerPC 970,
and those already require an ancient host kernel. TCG and KVM PR
guests with PowerPC 970 should still work.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Acked-by: Thomas Huth <thuth@redhat.com>