KVM: PPC: 44x: fix DCR read/write

commit e43a0287 upstream.

When remembering the direction of a DCR transaction, we should write
to the same variable that we interpret on later when doing vcpu_run
again.
Signed-off-by: Alexander Graf <agraf@suse.de>
[bwh: Backported to 3.2: adjust context, indentation]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

arch/powerpc/kvm/44x_emulate.c

@@ -79,6 +79,7 @@ int kvmppc_core_emulate_op(struct kvm_run *run, struct kvm_vcpu *vcpu,
 				run->dcr.dcrn = dcrn;
 				run->dcr.data =  0;
 				run->dcr.is_write = 0;
+				vcpu->arch.dcr_is_write = 0;
 				vcpu->arch.io_gpr = rt;
 				vcpu->arch.dcr_needed = 1;
 				kvmppc_account_exit(vcpu, DCR_EXITS);
@@ -100,6 +101,7 @@ int kvmppc_core_emulate_op(struct kvm_run *run, struct kvm_vcpu *vcpu,
 				run->dcr.dcrn = dcrn;
 				run->dcr.data = kvmppc_get_gpr(vcpu, rs);
 				run->dcr.is_write = 1;
+				vcpu->arch.dcr_is_write = 1;
 				vcpu->arch.dcr_needed = 1;
 				kvmppc_account_exit(vcpu, DCR_EXITS);
 				emulated = EMULATE_DO_DCR;