diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/net/team/team_core.c | 45 |
1 files changed, 32 insertions, 13 deletions
diff --git a/drivers/net/team/team_core.c b/drivers/net/team/team_core.c index 0c87f9972457..f51388d50307 100644 --- a/drivers/net/team/team_core.c +++ b/drivers/net/team/team_core.c @@ -534,21 +534,23 @@ static void team_adjust_ops(struct team *team) if (!team->tx_en_port_count || !team_is_mode_set(team) || !team->mode->ops->transmit) - team->ops.transmit = team_dummy_transmit; + WRITE_ONCE(team->ops.transmit, team_dummy_transmit); else - team->ops.transmit = team->mode->ops->transmit; + WRITE_ONCE(team->ops.transmit, team->mode->ops->transmit); if (!team->rx_en_port_count || !team_is_mode_set(team) || !team->mode->ops->receive) - team->ops.receive = team_dummy_receive; + WRITE_ONCE(team->ops.receive, team_dummy_receive); else - team->ops.receive = team->mode->ops->receive; + WRITE_ONCE(team->ops.receive, team->mode->ops->receive); } /* - * We can benefit from the fact that it's ensured no port is present - * at the time of mode change. Therefore no packets are in fly so there's no - * need to set mode operations in any special way. + * team_change_mode() ensures no ports are present during mode change, + * but lockless readers can still reach team_xmit(). Avoid touching + * transmit/receive -- they are already set to dummies by + * team_adjust_ops() since no ports are enabled. synchronize_net() + * drains in-flight readers before destroying old mode state. */ static int __team_change_mode(struct team *team, const struct team_mode *new_mode) @@ -557,9 +559,21 @@ static int __team_change_mode(struct team *team, if (team_is_mode_set(team)) { void (*exit_op)(struct team *team) = team->ops.exit; - /* Clear ops area so no callback is called any longer */ - memset(&team->ops, 0, sizeof(struct team_mode_ops)); - team_adjust_ops(team); + /* Clear cold-path ops used only under RTNL. transmit and + * receive are already dummies (no ports) so leave them + * alone -- overwriting them is the source of the race. + */ + team->ops.init = NULL; + team->ops.exit = NULL; + team->ops.port_enter = NULL; + team->ops.port_leave = NULL; + team->ops.port_change_dev_addr = NULL; + team->ops.port_tx_disabled = NULL; + + /* Wait for in-flight readers before tearing down mode + * state they may reference. + */ + synchronize_net(); if (exit_op) exit_op(team); @@ -582,7 +596,12 @@ static int __team_change_mode(struct team *team, } team->mode = new_mode; - memcpy(&team->ops, new_mode->ops, sizeof(struct team_mode_ops)); + team->ops.init = new_mode->ops->init; + team->ops.exit = new_mode->ops->exit; + team->ops.port_enter = new_mode->ops->port_enter; + team->ops.port_leave = new_mode->ops->port_leave; + team->ops.port_change_dev_addr = new_mode->ops->port_change_dev_addr; + team->ops.port_tx_disabled = new_mode->ops->port_tx_disabled; team_adjust_ops(team); return 0; @@ -743,7 +762,7 @@ static rx_handler_result_t team_handle_frame(struct sk_buff **pskb) /* allow exact match delivery for disabled ports */ res = RX_HANDLER_EXACT; } else { - res = team->ops.receive(team, port, skb); + res = READ_ONCE(team->ops.receive)(team, port, skb); } if (res == RX_HANDLER_ANOTHER) { struct team_pcpu_stats *pcpu_stats; @@ -1845,7 +1864,7 @@ static netdev_tx_t team_xmit(struct sk_buff *skb, struct net_device *dev) tx_success = team_queue_override_transmit(team, skb); if (!tx_success) - tx_success = team->ops.transmit(team, skb); + tx_success = READ_ONCE(team->ops.transmit)(team, skb); if (tx_success) { struct team_pcpu_stats *pcpu_stats; |