[PATCH v11 18/24] coresight: cti: Fix bug clearing sysfs links on callback

Tingwei Zhang
2020-09-15T10:45:08Z

From: Mike Leach <mike.leach@linaro.org>

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@codeaurora.org>
Signed-off-by: Mike Leach <mike.leach@linaro.org>
Signed-off-by: Tingwei Zhang <tingwei@codeaurora.org>
Acked-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.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 abc8b32e79b3..38e785d913b0 100644
--- a/drivers/hwtracing/coresight/coresight-cti.c
+++ b/drivers/hwtracing/coresight/coresight-cti.c
@@ -591,7 +591,7 @@ static 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 4f4485b17458..b8b0a20e93c9 100644
--- a/drivers/hwtracing/coresight/coresight.c
+++ b/drivers/hwtracing/coresight/coresight.c
@@ -1246,8 +1246,6 @@ 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);
@@ -1582,6 +1580,8 @@ 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);