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

[Todd Poynor]

From: Todd Poynor <toddpoy...@google.com>

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

Signed-off-by: Zhongze Hu <fran...@chromium.org>
Signed-off-by: Todd Poynor <toddpoy...@google.com>
---
 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