In case when vcpus are explicitly enabled/disabled in a non-consecutive order within a libvirt xml, it results in a drc index mismatch during vcpu hotplug later because the existing logic uses vcpu id to derive the corresponding drc index which is not correct. Use env->core_index to derive a vcpu's drc index as appropriate to fix this issue. For ex, for the given libvirt xml config: <vcpus> <vcpu id='0' enabled='yes' hotpluggable='no'/> <vcpu id='1' enabled='yes' hotpluggable='yes'/> <vcpu id='2' enabled='no' hotpluggable='yes'/> <vcpu id='3' enabled='yes' hotpluggable='yes'/> <vcpu id='4' enabled='no' hotpluggable='yes'/> <vcpu id='5' enabled='yes' hotpluggable='yes'/> <vcpu id='6' enabled='no' hotpluggable='yes'/> <vcpu id='7' enabled='no' hotpluggable='yes'/> </vcpus> We see below error on guest console with "virsh setvcpus <domain> 5" : pseries-hotplug-cpu: CPU with drc index 10000002 already exists This patch fixes the issue by using correct drc index for explicitly enabled vcpus during init. Reported-by: Anushree Mathur <anushree.mathur@linux.vnet.ibm.com> Tested-by: Anushree Mathur <anushree.mathur@linux.vnet.ibm.com> Signed-off-by: Harsh Prateek Bora <harshpb@linux.ibm.com> Reviewed-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Nicholas Piggin <npiggin@gmail.com>