Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit d725c7ac authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge branch 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 

Pull CPU hotplug fix from Thomas Gleixner:
 "A single fix to handle the removal of the first dynamic CPU hotplug
  state correctly"

* 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  smp/hotplug: Handle removal correctly in cpuhp_store_callbacks()
parents 93cc1228 0c96b273

kernel/cpu.c

+11 −1
Original line number Diff line number Diff line
@@ -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;