KVM: PPC: Book3S HV nestedv2: Do not call H_COPY_TOFROM_GUEST

H_COPY_TOFROM_GUEST is part of the nestedv1 API and so should not be
called by a nestedv2 host. Do not attempt to call it.
Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20231201132618.555031-10-vaibhav@linux.ibm.com

arch/powerpc/kvm/book3s_64_mmu_radix.c

@@ -40,6 +40,9 @@ unsigned long __kvmhv_copy_tofrom_guest_radix(int lpid, int pid,
 	unsigned long quadrant, ret = n;
 	bool is_load = !!to;
 
+	if (kvmhv_is_nestedv2())
+		return H_UNSUPPORTED;
+
 	/* Can't access quadrants 1 or 2 in non-HV mode, call the HV to do it */
 	if (kvmhv_on_pseries())
 		return plpar_hcall_norets(H_COPY_TOFROM_GUEST, lpid, pid, eaddr,