diff mbox series

[net-next,04/12] net: dpaa2-mac: remove defensive check in dpaa2_mac_disconnect()

Message ID 20221129141221.872653-5-vladimir.oltean@nxp.com
State New
Headers
Series Fix rtnl_mutex deadlock with DPAA2 and SFP modules |

Commit Message

Vladimir Oltean Nov. 29, 2022, 2:12 p.m. UTC 
  dpaa2_mac_disconnect() will only be called with a NULL mac->phylink if
dpaa2_mac_connect() failed, or was never called.

The callers are these:

dpaa2_eth_disconnect_mac():

	if (dpaa2_eth_is_type_phy(priv))
		dpaa2_mac_disconnect(priv->mac);

dpaa2_switch_port_disconnect_mac():

	if (dpaa2_switch_port_is_type_phy(port_priv))
		dpaa2_mac_disconnect(port_priv->mac);

priv->mac can be NULL, but in that case, dpaa2_eth_is_type_phy() returns
false, and dpaa2_mac_disconnect() is never called. Similar for
dpaa2-switch.

When priv->mac is non-NULL, it means that dpaa2_mac_connect() returned
zero (success), and therefore, priv->mac->phylink is also a valid
pointer.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
---
 drivers/net/ethernet/freescale/dpaa2/dpaa2-mac.c | 3 ---
 1 file changed, 3 deletions(-)

Comments

Andrew Lunn Nov. 29, 2022, 6:51 p.m. UTC | #1 
On Tue, Nov 29, 2022 at 04:12:13PM +0200, Vladimir Oltean wrote:
> dpaa2_mac_disconnect() will only be called with a NULL mac->phylink if
> dpaa2_mac_connect() failed, or was never called.
> 
> The callers are these:
> 
> dpaa2_eth_disconnect_mac():
> 
> 	if (dpaa2_eth_is_type_phy(priv))
> 		dpaa2_mac_disconnect(priv->mac);
> 
> dpaa2_switch_port_disconnect_mac():
> 
> 	if (dpaa2_switch_port_is_type_phy(port_priv))
> 		dpaa2_mac_disconnect(port_priv->mac);
> 
> priv->mac can be NULL, but in that case, dpaa2_eth_is_type_phy() returns
> false, and dpaa2_mac_disconnect() is never called. Similar for
> dpaa2-switch.
> 
> When priv->mac is non-NULL, it means that dpaa2_mac_connect() returned
> zero (success), and therefore, priv->mac->phylink is also a valid
> pointer.
> 
> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>

Reviewed-by: Andrew Lunn <andrew@lunn.ch>

    Andrew
diff mbox series

Patch

diff --git a/drivers/net/ethernet/freescale/dpaa2/dpaa2-mac.c b/drivers/net/ethernet/freescale/dpaa2/dpaa2-mac.c
index c22ce1c871f3..9d1e7026eaef 100644
--- a/drivers/net/ethernet/freescale/dpaa2/dpaa2-mac.c
+++ b/drivers/net/ethernet/freescale/dpaa2/dpaa2-mac.c
@@ -449,9 +449,6 @@  int dpaa2_mac_connect(struct dpaa2_mac *mac)
 
 void dpaa2_mac_disconnect(struct dpaa2_mac *mac)
 {
-	if (!mac->phylink)
-		return;
-
 	phylink_disconnect_phy(mac->phylink);
 	phylink_destroy(mac->phylink);
 	dpaa2_pcs_destroy(mac);