diff options
| author | Johan Hovold <johan@hovoldconsulting.com> | 2015-07-09 15:17:58 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@google.com> | 2015-07-13 15:29:27 -0700 |
| commit | 85109f7ddde4b1842bfb08741a8b461e31ef2c4f (patch) | |
| tree | 4bd94039cb5d36bd53f8299b5fb4634474d734d7 /drivers/staging/greybus/operation.c | |
| parent | 5c1ac6945526c76258869c8c04632ab5ae61bdab (diff) | |
greybus: operation: fix operation-destroy race
Make sure to acquire the connection-list lock atomically when releasing
the final reference.
This allows the list to be traversed and references to be acquired
(while holding the lock) without racing with the destructor.
Suggested-by: Greg Kroah-Hartman <gregkh@google.com>
Signed-off-by: Johan Hovold <johan@hovoldconsulting.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Diffstat (limited to 'drivers/staging/greybus/operation.c')
| -rw-r--r-- | drivers/staging/greybus/operation.c | 11 |
1 files changed, 6 insertions, 5 deletions
diff --git a/drivers/staging/greybus/operation.c b/drivers/staging/greybus/operation.c index 9e2ff7dd278a..f8d7df9ad3c4 100644 --- a/drivers/staging/greybus/operation.c +++ b/drivers/staging/greybus/operation.c @@ -528,14 +528,12 @@ EXPORT_SYMBOL_GPL(gb_operation_get); static void _gb_operation_destroy(struct kref *kref) { struct gb_operation *operation; - unsigned long flags; operation = container_of(kref, struct gb_operation, kref); /* XXX Make sure it's not in flight */ - spin_lock_irqsave(&gb_operations_lock, flags); list_del(&operation->links); - spin_unlock_irqrestore(&gb_operations_lock, flags); + spin_unlock(&gb_operations_lock); if (operation->response) gb_operation_message_free(operation->response); @@ -550,8 +548,11 @@ static void _gb_operation_destroy(struct kref *kref) */ void gb_operation_put(struct gb_operation *operation) { - if (!WARN_ON(!operation)) - kref_put(&operation->kref, _gb_operation_destroy); + if (WARN_ON(!operation)) + return; + + kref_put_spinlock_irqsave(&operation->kref, _gb_operation_destroy, + &gb_operations_lock); } EXPORT_SYMBOL_GPL(gb_operation_put); |