[PATCH v6 09/13] coresight: etm4x: missing cscfg_csdev_disable_active_config() in perf enable

Yeoreum Yun
2026-04-22T13:22:43Z

In the perf enable path, there are missing cases where
cscfg_csdev_disable_active_config() is not called:

- Branch broadcast is selected but not supported by the hardware
- etm4_enable_hw() fails

This can lead to a leak of config_desc->active_cnt.
Fix this by properly calling cscfg_csdev_disable_active_config()
in these error paths.

Fixes: 810ac401db1f ("coresight: etm4x: Add complex configuration handlers to etmv4")
Signed-off-by: Yeoreum Yun <yeoreum.yun@arm.com>
---
.../hwtracing/coresight/coresight-etm4x-core.c | 17 +++++++++++++----
1 file changed, 13 insertions(+), 4 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-etm4x-core.c b/drivers/hwtracing/coresight/coresight-etm4x-core.c
index 66d09e0a4171..d6fd6125ef60 100644
--- a/drivers/hwtracing/coresight/coresight-etm4x-core.c
+++ b/drivers/hwtracing/coresight/coresight-etm4x-core.c
@@ -895,6 +895,8 @@ static int etm4_parse_event_config(struct coresight_device *csdev,
* Missing BB support could cause silent decode errors
* so fail to open if it's not supported.
*/
+ if (cfg_hash)
+ cscfg_csdev_disable_active_config(csdev);
ret = -EINVAL;
goto out;
} else {
@@ -911,6 +913,7 @@ static int etm4_enable_perf(struct coresight_device *csdev,
struct coresight_path *path)
{
struct etmv4_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
+ struct perf_event_attr *attr = &event->attr;
int ret;

if (WARN_ON_ONCE(drvdata->cpu != smp_processor_id()))
@@ -922,7 +925,7 @@ static int etm4_enable_perf(struct coresight_device *csdev,
/* Configure the tracer based on the session's specifics */
ret = etm4_parse_event_config(csdev, event);
if (ret)
- goto out;
+ goto err;

drvdata->trcid = path->trace_id;

@@ -931,11 +934,17 @@ static int etm4_enable_perf(struct coresight_device *csdev,

/* And enable it */
ret = etm4_enable_hw(drvdata);
+ if (ret) {
+ if (ATTR_CFG_GET_FLD(attr, configid))
+ cscfg_csdev_disable_active_config(csdev);
+ goto err;
+ }

-out:
+ return 0;
+
+err:
/* Failed to start tracer; roll back to DISABLED mode */
- if (ret)
- coresight_set_mode(csdev, CS_MODE_DISABLED);
+ coresight_set_mode(csdev, CS_MODE_DISABLED);
return ret;