Commit 11e1a164 authored by Viresh Kumar's avatar Viresh Kumar
Browse files

opp: Don't decrement uninitialized list_kref 



The list_kref was added for static OPPs and to track their users. The
kref is initialized while the static OPPs are added, but removed
unconditionally even if the static OPPs were never added. This causes
refcount mismatch warnings currently.

Fix that by always initializing the kref when the OPP table is first
initialized. The refcount is later incremented only for the second user
onwards.

Fixes: d0e8ae6c ("OPP: Create separate kref for static OPPs list")
Reported-by: default avatarRajendra Nayak <rnayak@codeaurora.org>
Signed-off-by: default avatarViresh Kumar <viresh.kumar@linaro.org>
parent 71419d84

drivers/opp/core.c

+1 −0
Original line number Diff line number Diff line
@@ -988,6 +988,7 @@ static struct opp_table *_allocate_opp_table(struct device *dev, int index) 
	BLOCKING_INIT_NOTIFIER_HEAD(&opp_table->head);

	INIT_LIST_HEAD(&opp_table->opp_list);

	kref_init(&opp_table->kref);

	kref_init(&opp_table->list_kref);



	/* Secure the device table modification */

	list_add(&opp_table->node, &opp_tables);

drivers/opp/of.c

+4 −17
Original line number Diff line number Diff line
@@ -662,8 +662,6 @@ static int _of_add_opp_table_v2(struct device *dev, struct opp_table *opp_table) 
		return 0;

	}



	kref_init(&opp_table->list_kref);



	/* We have opp-table node now, iterate over it and add OPPs */

	for_each_available_child_of_node(opp_table->np, np) {

		opp = _opp_add_static_v2(opp_table, dev, np);
@@ -672,17 +670,15 @@ static int _of_add_opp_table_v2(struct device *dev, struct opp_table *opp_table) 
			dev_err(dev, "%s: Failed to add OPP, %d\n", __func__,

				ret);

			of_node_put(np);

			goto put_list_kref;

			return ret;

		} else if (opp) {

			count++;

		}

	}



	/* There should be one of more OPP defined */

	if (WARN_ON(!count)) {

		ret = -ENOENT;

		goto put_list_kref;

	}

	if (WARN_ON(!count))

		return -ENOENT;



	list_for_each_entry(opp, &opp_table->opp_list, node)

		pstate_count += !!opp->pstate;
@@ -691,8 +687,7 @@ static int _of_add_opp_table_v2(struct device *dev, struct opp_table *opp_table) 
	if (pstate_count && pstate_count != count) {

		dev_err(dev, "Not all nodes have performance state set (%d: %d)\n",

			count, pstate_count);

		ret = -ENOENT;

		goto put_list_kref;

		return -ENOENT;

	}



	if (pstate_count)
@@ -701,11 +696,6 @@ static int _of_add_opp_table_v2(struct device *dev, struct opp_table *opp_table) 
	opp_table->parsed_static_opps = true;



	return 0;



put_list_kref:

	_put_opp_list_kref(opp_table);



	return ret;

}



/* Initializes OPP tables based on old-deprecated bindings */
@@ -731,8 +721,6 @@ static int _of_add_opp_table_v1(struct device *dev, struct opp_table *opp_table) 
		return -EINVAL;

	}



	kref_init(&opp_table->list_kref);



	val = prop->value;

	while (nr) {

		unsigned long freq = be32_to_cpup(val++) * 1000;
@@ -742,7 +730,6 @@ static int _of_add_opp_table_v1(struct device *dev, struct opp_table *opp_table) 
		if (ret) {

			dev_err(dev, "%s: Failed to add OPP %ld (%d)\n",

				__func__, freq, ret);

			_put_opp_list_kref(opp_table);

			return ret;

		}

		nr -= 2;

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