struct cpuhp_step *sp;
int ret = 0;
- if (state == CPUHP_AP_ONLINE_DYN || state == CPUHP_BP_PREPARE_DYN) {
+ /*
+ * If name is NULL, then the state gets removed.
+ *
+ * CPUHP_AP_ONLINE_DYN and CPUHP_BP_PREPARE_DYN are handed out on
+ * the first allocation from these dynamic ranges, so the removal
+ * would trigger a new allocation and clear the wrong (already
+ * empty) state, leaving the callbacks of the to be cleared state
+ * dangling, which causes wreckage on the next hotplug operation.
+ */
+ if (name && (state == CPUHP_AP_ONLINE_DYN ||
+ state == CPUHP_BP_PREPARE_DYN)) {
ret = cpuhp_reserve_state(state);
if (ret < 0)
return ret;