[PATCH RFC v3 1/7] soc: qcom: pdr: protect locator_addr with the main mutex

[Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>]

If the service locator server is restarted fast enough, the PDR can
rewrite locator_addr fields concurrently. Protect them by placing
modification of those fields under the main pdr->lock.

Fixes: fbe639b44a82 ("soc: qcom: Introduce Protection Domain Restart helpers")
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
---
 drivers/soc/qcom/pdr_interface.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/soc/qcom/pdr_interface.c b/drivers/soc/qcom/pdr_interface.c
index a1b6a4081dea..7b5fdf9fd3d7 100644
--- a/drivers/soc/qcom/pdr_interface.c
+++ b/drivers/soc/qcom/pdr_interface.c
@@ -76,12 +76,12 @@ static int pdr_locator_new_server(struct qmi_handle *qmi,
 					      locator_hdl);
 	struct pdr_service *pds;
 
+	mutex_lock(&pdr->lock);
 	/* Create a local client port for QMI communication */
 	pdr->locator_addr.sq_family = AF_QIPCRTR;
 	pdr->locator_addr.sq_node = svc->node;
 	pdr->locator_addr.sq_port = svc->port;
 
-	mutex_lock(&pdr->lock);
 	pdr->locator_init_complete = true;
 	mutex_unlock(&pdr->lock);
 
@@ -104,10 +104,10 @@ static void pdr_locator_del_server(struct qmi_handle *qmi,
 
 	mutex_lock(&pdr->lock);
 	pdr->locator_init_complete = false;
-	mutex_unlock(&pdr->lock);
 
 	pdr->locator_addr.sq_node = 0;
 	pdr->locator_addr.sq_port = 0;
+	mutex_unlock(&pdr->lock);
 }
 
 static const struct qmi_ops pdr_locator_ops = {
@@ -133,11 +133,13 @@ static int pdr_register_listener(struct pdr_handle *pdr,
 	req.enable = enable;
 	strscpy(req.service_path, pds->service_path, sizeof(req.service_path));
 
+	mutex_lock(&pdr->lock);
 	ret = qmi_send_request(&pdr->notifier_hdl, &pds->addr,
 			       &txn, SERVREG_REGISTER_LISTENER_REQ,
 			       SERVREG_REGISTER_LISTENER_REQ_LEN,
 			       servreg_register_listener_req_ei,
 			       &req);
+	mutex_unlock(&pdr->lock);
 	if (ret < 0) {
 		qmi_txn_cancel(&txn);
 		return ret;

-- 
2.39.2