[PATCH v6 19/25] coresight: cti: Fix bug clearing sysfs links on callback

Tingwei Zhang tingwei at codeaurora.org
Fri Jul 31 02:40:06 EDT 2020


During module unload, a coresight driver module will call back into
the CTI driver to remove any links between the two devices.

The current code has 2 issues:-
1) in the CTI driver the matching code is matching to the wrong device
so misses all the links.
2) The callback is called too late in the unload process resulting in a
crash.

This fixes both the issues.

Fixes: 177af8285b59 (coresight: cti: Enable CTI associated with devices)
Reported-by: Tingwei Zhang <tingwei at codeaurora.org>
Signed-off-by: Mike Leach <mike.leach at linaro.org>
Signed-off-by: Tingwei Zhang <tingwei at codeaurora.org>
---
 drivers/hwtracing/coresight/coresight-cti.c | 2 +-
 drivers/hwtracing/coresight/coresight.c     | 4 ++--
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-cti.c b/drivers/hwtracing/coresight/coresight-cti.c
index 1c34db7d1b1b..6bb06c5715db 100644
--- a/drivers/hwtracing/coresight/coresight-cti.c
+++ b/drivers/hwtracing/coresight/coresight-cti.c
@@ -608,7 +608,7 @@ void cti_remove_assoc_from_csdev(struct coresight_device *csdev)
 		ctidrv = csdev_to_cti_drvdata(csdev->ect_dev);
 		ctidev = &ctidrv->ctidev;
 		list_for_each_entry(tc, &ctidev->trig_cons, node) {
-			if (tc->con_dev == csdev->ect_dev) {
+			if (tc->con_dev == csdev) {
 				cti_remove_sysfs_link(ctidrv, tc);
 				tc->con_dev = NULL;
 				break;
diff --git a/drivers/hwtracing/coresight/coresight.c b/drivers/hwtracing/coresight/coresight.c
index 25578579559b..8b55383cfcf1 100644
--- a/drivers/hwtracing/coresight/coresight.c
+++ b/drivers/hwtracing/coresight/coresight.c
@@ -1238,8 +1238,6 @@ static void coresight_device_release(struct device *dev)
 {
 	struct coresight_device *csdev = to_coresight_device(dev);
 
-	if (cti_assoc_ops && cti_assoc_ops->remove)
-		cti_assoc_ops->remove(csdev);
 	fwnode_handle_put(csdev->dev.fwnode);
 	kfree(csdev->refcnt);
 	kfree(csdev);
@@ -1574,6 +1572,8 @@ void coresight_unregister(struct coresight_device *csdev)
 {
 	etm_perf_del_symlink_sink(csdev);
 	/* Remove references of that device in the topology */
+	if (cti_assoc_ops && cti_assoc_ops->remove)
+		cti_assoc_ops->remove(csdev);
 	coresight_remove_conns(csdev);
 	coresight_clear_default_sink(csdev);
 	coresight_release_platform_data(csdev, csdev->pdata);
-- 
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