Commit 8fb22264 authored by Pawel Moll's avatar Pawel Moll Committed by Kevin Hilman
Browse files

bus: arm-ccn: Move event cleanup routine 



The function cleaning up an initialized event
was called from the "event_del" handler, instead
of being used as the "destroy" callback. In case of
events group allocation this caused NULL pointer
dereference (as events are added and deleted
multiple times then). Fixed now.

Signed-off-by: default avatarPawel Moll <mail@pawelmoll.com>
Signed-off-by: default avatarKevin Hilman <khilman@linaro.org>
parent 95f6e814

drivers/bus/arm-ccn.c

+25 −26
Original line number Diff line number Diff line
@@ -586,6 +586,30 @@ static int arm_ccn_pmu_type_eq(u32 a, u32 b) 
	return 0;

}



static void arm_ccn_pmu_event_destroy(struct perf_event *event)

{

	struct arm_ccn *ccn = pmu_to_arm_ccn(event->pmu);

	struct hw_perf_event *hw = &event->hw;



	if (hw->idx == CCN_IDX_PMU_CYCLE_COUNTER) {

		clear_bit(CCN_IDX_PMU_CYCLE_COUNTER, ccn->dt.pmu_counters_mask);

	} else {

		struct arm_ccn_component *source =

				ccn->dt.pmu_counters[hw->idx].source;



		if (CCN_CONFIG_TYPE(event->attr.config) == CCN_TYPE_XP &&

				CCN_CONFIG_EVENT(event->attr.config) ==

				CCN_EVENT_WATCHPOINT)

			clear_bit(hw->config_base, source->xp.dt_cmp_mask);

		else

			clear_bit(hw->config_base, source->pmu_events_mask);

		clear_bit(hw->idx, ccn->dt.pmu_counters_mask);

	}



	ccn->dt.pmu_counters[hw->idx].source = NULL;

	ccn->dt.pmu_counters[hw->idx].event = NULL;

}



static int arm_ccn_pmu_event_init(struct perf_event *event)

{

	struct arm_ccn *ccn;
@@ -599,6 +623,7 @@ static int arm_ccn_pmu_event_init(struct perf_event *event) 
		return -ENOENT;



	ccn = pmu_to_arm_ccn(event->pmu);

	event->destroy = arm_ccn_pmu_event_destroy;



	if (hw->sample_period) {

		dev_warn(ccn->dev, "Sampling not supported!\n");
@@ -731,30 +756,6 @@ static int arm_ccn_pmu_event_init(struct perf_event *event) 
	return 0;

}



static void arm_ccn_pmu_event_free(struct perf_event *event)

{

	struct arm_ccn *ccn = pmu_to_arm_ccn(event->pmu);

	struct hw_perf_event *hw = &event->hw;



	if (hw->idx == CCN_IDX_PMU_CYCLE_COUNTER) {

		clear_bit(CCN_IDX_PMU_CYCLE_COUNTER, ccn->dt.pmu_counters_mask);

	} else {

		struct arm_ccn_component *source =

				ccn->dt.pmu_counters[hw->idx].source;



		if (CCN_CONFIG_TYPE(event->attr.config) == CCN_TYPE_XP &&

				CCN_CONFIG_EVENT(event->attr.config) ==

				CCN_EVENT_WATCHPOINT)

			clear_bit(hw->config_base, source->xp.dt_cmp_mask);

		else

			clear_bit(hw->config_base, source->pmu_events_mask);

		clear_bit(hw->idx, ccn->dt.pmu_counters_mask);

	}



	ccn->dt.pmu_counters[hw->idx].source = NULL;

	ccn->dt.pmu_counters[hw->idx].event = NULL;

}



static u64 arm_ccn_pmu_read_counter(struct arm_ccn *ccn, int idx)

{

	u64 res;
@@ -1027,8 +1028,6 @@ static int arm_ccn_pmu_event_add(struct perf_event *event, int flags) 
static void arm_ccn_pmu_event_del(struct perf_event *event, int flags)

{

	arm_ccn_pmu_event_stop(event, PERF_EF_UPDATE);



	arm_ccn_pmu_event_free(event);

}



static void arm_ccn_pmu_event_read(struct perf_event *event)

CRA Git | Maintained and supported by SUSTech CRA and CCSE