[PATCH v7 09/13] coresight: etm4x: missing cscfg_csdev_disable_active_config() in perf enable

Yeoreum Yun yeoreum.yun at arm.com
Tue May 19 08:48:08 PDT 2026


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 at arm.com>
---
 .../hwtracing/coresight/coresight-etm4x-core.c | 18 ++++++++++++------
 1 file changed, 12 insertions(+), 6 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-etm4x-core.c b/drivers/hwtracing/coresight/coresight-etm4x-core.c
index f0a9f2ef4b27..0889937811cb 100644
--- a/drivers/hwtracing/coresight/coresight-etm4x-core.c
+++ b/drivers/hwtracing/coresight/coresight-etm4x-core.c
@@ -899,6 +899,8 @@ 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 {
@@ -915,6 +917,7 @@ 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()))
@@ -926,7 +929,7 @@ 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;
 
@@ -935,16 +938,19 @@ static int etm4_enable_perf(struct coresight_device *csdev,
 
 	/* And enable it */
 	ret = etm4_enable_hw(drvdata);
-
-out:
-	/* Failed to start tracer; roll back to DISABLED mode */
 	if (ret) {
-		coresight_set_mode(csdev, CS_MODE_DISABLED);
-		return ret;
+		if (ATTR_CFG_GET_FLD(attr, configid))
+			cscfg_csdev_disable_active_config(csdev);
+		goto err;
 	}
 
 	csdev->path = path;
 	return 0;
+
+err:
+	/* Failed to start tracer; roll back to DISABLED mode */
+	coresight_set_mode(csdev, CS_MODE_DISABLED);
+	return ret;
 }
 
 static int etm4_enable_sysfs(struct coresight_device *csdev, struct coresight_path *path)
-- 
LEVI:{C3F47F37-75D8-414A-A8BA-3980EC8A46D7}




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