vhost: add __rcu annotations
Also add rcu_dereference_protected() for code paths where locks are held.
Signed-off-by: Arnd Bergmann <[email protected]>
Signed-off-by: Paul E. McKenney <[email protected]>
Cc: "Michael S. Tsirkin" <[email protected]>
diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h
index afd7729..af3c11d 100644
--- a/drivers/vhost/vhost.h
+++ b/drivers/vhost/vhost.h
@@ -106,7 +106,7 @@
* vhost_work execution acts instead of rcu_read_lock() and the end of
* vhost_work execution acts instead of rcu_read_lock().
* Writers use virtqueue mutex. */
- void *private_data;
+ void __rcu *private_data;
/* Log write descriptors */
void __user *log_base;
struct vhost_log log[VHOST_NET_MAX_SG];
@@ -116,7 +116,7 @@
/* Readers use RCU to access memory table pointer
* log base pointer and features.
* Writers use mutex below.*/
- struct vhost_memory *memory;
+ struct vhost_memory __rcu *memory;
struct mm_struct *mm;
struct mutex mutex;
unsigned acked_features;
@@ -173,7 +173,11 @@
static inline int vhost_has_feature(struct vhost_dev *dev, int bit)
{
- unsigned acked_features = rcu_dereference(dev->acked_features);
+ unsigned acked_features;
+
+ acked_features =
+ rcu_dereference_index_check(dev->acked_features,
+ lockdep_is_held(&dev->mutex));
return acked_features & (1 << bit);
}
