@@ -1769,6 +1769,23 @@ static void pc_cpu_unplug_request_cb(HotplugHandler *hotplug_dev,
goto out;
}
+ if (idx < pcms->possible_cpus->len - 1 &&
+ pcms->possible_cpus->cpus[idx + 1].cpu != NULL) {
+ X86CPU *cpu;
+
+ for (idx = pcms->possible_cpus->len - 1;
+ pcms->possible_cpus->cpus[idx].cpu == NULL; idx--) {
+ ;;
+ }
+
+ cpu = X86_CPU(pcms->possible_cpus->cpus[idx].cpu);
+ error_setg(&local_err, "CPU [socket-id: %u, core-id: %u,"
+ " thread-id: %u] should be removed first",
+ cpu->socket_id, cpu->core_id, cpu->thread_id);
+ goto out;
+
+ }
+
hhc = HOTPLUG_HANDLER_GET_CLASS(pcms->acpi_dev);
hhc->unplug_request(HOTPLUG_HANDLER(pcms->acpi_dev), dev, &local_err);
@@ -1867,6 +1884,23 @@ static void pc_cpu_pre_plug(HotplugHandler *hotplug_dev,
return;
}
+ if (idx != 0 && pcms->possible_cpus->cpus[idx - 1].cpu == NULL) {
+ PCMachineClass *pcmc = PC_MACHINE_GET_CLASS(pcms);
+
+ for (idx = 1; pcms->possible_cpus->cpus[idx].cpu != NULL; idx++) {
+ ;;
+ }
+
+ x86_topo_ids_from_apicid(pcms->possible_cpus->cpus[idx].arch_id,
+ smp_cores, smp_threads, &topo);
+
+ if (!pcmc->legacy_cpu_hotplug) {
+ error_setg(errp, "CPU [socket: %u, core: %u, thread: %u] should be"
+ " added first", topo.pkg_id, topo.core_id, topo.smt_id);
+ return;
+ }
+ }
+
/* if 'address' properties socket-id/core-id/thread-id are not set, set them
* so that query_hotpluggable_cpus would show correct values
*/
it will still allow us to use cpu_index as migration instance_id since when CPUs are added contiguously (from the first to the last) and removed in opposite order, cpu_index stays stable and it's reproducable on destination side. While there is work in progress to support migration when there are holes in cpu_index range resulting from out-of-order plug or unplug, this patch is intended as an interim solution until cpu_index usage is cleaned up. As result of this patch it would be possible to plug/unplug CPUs, but in limited order that doesn't break migration. Signed-off-by: Igor Mammedov <imammedo@redhat.com> --- v5: - move note from under --- to commit message itself so it won't be discarded along the way try to improve cmmit message Bandan Das <bsd@redhat.com> --- hw/i386/pc.c | 34 ++++++++++++++++++++++++++++++++++ 1 file changed, 34 insertions(+)