On 4/24/2024 2:27 AM, Dmitry Baryshkov wrote:
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")
Tested-by: Neil Armstrong <neil.armstrong@xxxxxxxxxx> # on SM8550-QRD
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
---
drivers/soc/qcom/pdr_interface.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/soc/qcom/pdr_interface.c b/drivers/soc/qcom/pdr_interface.c
index a1b6a4081dea..19cfe4b41235 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 = {
These two functions are provided as qmi_ops handlers in pdr_locator_ops.
Aren't they serialized in the qmi handle's workqueue since it as an
ordered_workqueue? Even in a fast pdr scenario I don't think we would
see a race condition between these two functions.
The other access these two functions do race against is in the
pdr_notifier_work. I think you would need to protect locator_addr in
pdr_get_domain_list since the qmi_send_request there uses
'pdr->locator_addr'.
Thanks!
Chris
