@@ -1743,8 +1743,8 @@ static struct rtnl_link_stats64 *efx_net_stats(struct net_device *net_dev, struc
struct efx_mac_stats *mac_stats = &efx->mac_stats;
spin_lock_bh(&efx->stats_lock);
+
efx->type->update_stats(efx);
- spin_unlock_bh(&efx->stats_lock);
stats->rx_packets = mac_stats->rx_packets;
stats->tx_packets = mac_stats->tx_packets;
@@ -1768,6 +1768,8 @@ static struct rtnl_link_stats64 *efx_net_stats(struct net_device *net_dev, struc
stats->tx_errors = (stats->tx_window_errors +
mac_stats->tx_bad);
+ spin_unlock_bh(&efx->stats_lock);
+
return stats;
}
@@ -489,13 +489,14 @@ static void efx_ethtool_get_stats(struct net_device *net_dev,
const struct efx_ethtool_stat *stat;
struct efx_channel *channel;
struct efx_tx_queue *tx_queue;
- struct rtnl_link_stats64 temp;
int i;
EFX_BUG_ON_PARANOID(stats->n_stats != EFX_ETHTOOL_NUM_STATS);
+ spin_lock_bh(&efx->stats_lock);
+
/* Update MAC and NIC statistics */
- dev_get_stats(net_dev, &temp);
+ efx->type->update_stats(efx);
/* Fill detailed statistics buffer */
for (i = 0; i < EFX_ETHTOOL_NUM_STATS; i++) {
@@ -525,6 +526,8 @@ static void efx_ethtool_get_stats(struct net_device *net_dev,
break;
}
}
+
+ spin_unlock_bh(&efx->stats_lock);
}
static void efx_ethtool_self_test(struct net_device *net_dev,
@@ -704,6 +704,7 @@ struct efx_filter_state;
* can provide. Generic code converts these into a standard
* &struct net_device_stats.
* @stats_lock: Statistics update lock. Serialises statistics fetches
+ * and access to @mac_stats.
*
* This is stored in the private area of the &struct net_device.
*/
efx_nic::stats_lock is used to serialise stats updates, but each reader was dropping it before it finished reading efx_nic::mac_stats. If there were concurrent stats reads using procfs, or one using procfs and one using ethtool, an update could race with a read. On a 32-bit system, the reader could see word-tearing of 64-bit stats (32 bits of the old value and 32 bits of the new). Signed-off-by: Ben Hutchings <bhutchings@solarflare.com> --- drivers/net/ethernet/sfc/efx.c | 4 +++- drivers/net/ethernet/sfc/ethtool.c | 7 +++++-- drivers/net/ethernet/sfc/net_driver.h | 1 + 3 files changed, 9 insertions(+), 3 deletions(-)