sfc: Use ACCESS_ONCE when copying efx_tx_queue::read_count

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>

1 files changed, 2 insertions, 3 deletions

diff --git a/drivers/net/sfc/tx.c b/drivers/net/sfc/tx.c
index 03194f7c0954..fef22351ddbd 100644
--- a/drivers/net/sfc/tx.c
+++ b/drivers/net/sfc/tx.c
@@ -240,8 +240,7 @@ netdev_tx_t efx_enqueue_skb(struct efx_tx_queue *tx_queue, struct sk_buff *skb)
                                  * of read_count. */
                                 smp_mb();
                                 tx_queue->old_read_count =
-                                        *(volatile unsigned *)
-                                        &tx_queue->read_count;
+                                        ACCESS_ONCE(tx_queue->read_count);
                                 fill_level = (tx_queue->insert_count
                                               - tx_queue->old_read_count);
                                 q_space = efx->txq_entries - 1 - fill_level;
@@ -764,7 +763,7 @@ static int efx_tx_queue_insert(struct efx_tx_queue *tx_queue,
                          * stopped from the access of read_count. */
                         smp_mb();
                         tx_queue->old_read_count =
-                                *(volatile unsigned *)&tx_queue->read_count;
+                                ACCESS_ONCE(tx_queue->read_count);
                         fill_level = (tx_queue->insert_count
                                       - tx_queue->old_read_count);
                         q_space = efx->txq_entries - 1 - fill_level;