From 8fb22264350d99793a12867f4e2a43e50150f778 Mon Sep 17 00:00:00 2001 From: Pawel Moll Date: Tue, 2 Sep 2014 16:26:11 +0100 Subject: [PATCH] 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: Pawel Moll Signed-off-by: Kevin Hilman --- drivers/bus/arm-ccn.c | 51 +++++++++++++++++++++---------------------- 1 file changed, 25 insertions(+), 26 deletions(-) diff --git a/drivers/bus/arm-ccn.c b/drivers/bus/arm-ccn.c index 6f550d9e7a2d..a60f26400705 100644 --- a/drivers/bus/arm-ccn.c +++ b/drivers/bus/arm-ccn.c @@ -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) -- 2.20.1