[PATCH 06/32] staging: gasket: hold mutex on gasket driver unregistration

From: Todd Poynor
Date: Tue Jul 17 2018 - 17:04:58 EST


From: Todd Poynor <toddpoynor@xxxxxxxxxx>

Take the global mutex on driver unregistration updates for proper
ordering of updates and consistent access procedures.

Signed-off-by: Zhongze Hu <frankhu@xxxxxxxxxxxx>
Signed-off-by: Todd Poynor <toddpoynor@xxxxxxxxxx>
---
drivers/staging/gasket/gasket_core.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/drivers/staging/gasket/gasket_core.c b/drivers/staging/gasket/gasket_core.c
index cbadab7544c81..2ff328652356a 100644
--- a/drivers/staging/gasket/gasket_core.c
+++ b/drivers/staging/gasket/gasket_core.c
@@ -371,7 +371,9 @@ int gasket_register_device(const struct gasket_driver_desc *driver_desc)
class_destroy(internal->class);

unregister_gasket_driver:
+ mutex_lock(&g_mutex);
g_descs[desc_idx].driver_desc = NULL;
+ mutex_unlock(&g_mutex);
return ret;
}
EXPORT_SYMBOL(gasket_register_device);
@@ -408,7 +410,9 @@ void gasket_unregister_device(const struct gasket_driver_desc *driver_desc)
class_destroy(internal_desc->class);

/* Finally, effectively "remove" the driver. */
+ mutex_lock(&g_mutex);
g_descs[desc_idx].driver_desc = NULL;
+ mutex_unlock(&g_mutex);

gasket_nodev_info("removed %s driver", driver_desc->name);
}
--
2.18.0.203.gfac676dfb9-goog