Commit a0490fa3 authored by Ingo Molnar's avatar Ingo Molnar
Browse files

sched: cpu hotplug fix 



rq_attach_root() does a kfree() with the runqueue lock held.

That's not a very wise move, fix it.

Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent b578f3fc

kernel/sched.c

+12 −3
Original line number Diff line number Diff line
@@ -6944,20 +6944,26 @@ static void free_rootdomain(struct root_domain *rd) 


static void rq_attach_root(struct rq *rq, struct root_domain *rd)

{

	struct root_domain *old_rd = NULL;

	unsigned long flags;



	spin_lock_irqsave(&rq->lock, flags);



	if (rq->rd) {

		struct root_domain *old_rd = rq->rd;

		old_rd = rq->rd;



		if (cpumask_test_cpu(rq->cpu, old_rd->online))

			set_rq_offline(rq);



		cpumask_clear_cpu(rq->cpu, old_rd->span);



		if (atomic_dec_and_test(&old_rd->refcount))

			free_rootdomain(old_rd);

		/*

		 * If we dont want to free the old_rt yet then

		 * set old_rd to NULL to skip the freeing later

		 * in this function:

		 */

		if (!atomic_dec_and_test(&old_rd->refcount))

			old_rd = NULL;

	}



	atomic_inc(&rd->refcount);
@@ -6968,6 +6974,9 @@ static void rq_attach_root(struct rq *rq, struct root_domain *rd) 
		set_rq_online(rq);



	spin_unlock_irqrestore(&rq->lock, flags);



	if (old_rd)

		free_rootdomain(old_rd);

}



static int __init_refok init_rootdomain(struct root_domain *rd, bool bootmem)