bus: arm-ccn: Fix error handling at event allocation
The bitfield allocation function returns error condition
as a negative value, but in two cases its result
was assigned to an unsigned member of the hw_perf_event
structure, thus the error would not be ever detected.
Fixed by using an intermediate, signed variable.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Pawel Moll <pawel.moll@arm.com>
Signed-off-by: Olof Johansson <olof@lixom.net>
diff --git a/drivers/bus/arm-ccn.c b/drivers/bus/arm-ccn.c
index 4f86bbb..3266f8f 100644
--- a/drivers/bus/arm-ccn.c
+++ b/drivers/bus/arm-ccn.c
@@ -591,7 +591,7 @@
struct arm_ccn *ccn;
struct hw_perf_event *hw = &event->hw;
u32 node_xp, type, event_id;
- int valid;
+ int valid, bit;
struct arm_ccn_component *source;
int i;
@@ -713,17 +713,18 @@
/* Allocate an event source or a watchpoint */
if (type == CCN_TYPE_XP && event_id == CCN_EVENT_WATCHPOINT)
- hw->config_base = arm_ccn_pmu_alloc_bit(source->xp.dt_cmp_mask,
+ bit = arm_ccn_pmu_alloc_bit(source->xp.dt_cmp_mask,
CCN_NUM_XP_WATCHPOINTS);
else
- hw->config_base = arm_ccn_pmu_alloc_bit(source->pmu_events_mask,
+ bit = arm_ccn_pmu_alloc_bit(source->pmu_events_mask,
CCN_NUM_PMU_EVENTS);
- if (hw->config_base < 0) {
+ if (bit < 0) {
dev_warn(ccn->dev, "No more event sources/watchpoints on node/XP %d!\n",
node_xp);
clear_bit(hw->idx, ccn->dt.pmu_counters_mask);
return -EAGAIN;
}
+ hw->config_base = bit;
ccn->dt.pmu_counters[hw->idx].event = event;