diff options
| -rw-r--r-- | kernel/cpu.c | 12 |
1 files changed, 11 insertions, 1 deletions
diff --git a/kernel/cpu.c b/kernel/cpu.c index bfbd649ccdc8..acf5308fad51 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -1253,7 +1253,17 @@ static int cpuhp_store_callbacks(enum cpuhp_state state, const char *name, 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; |