Searched hist:"2291982 e29b1aa6e628d3072ef533aeb6299945f" (Results 1 – 3 of 3) sorted by relevance
/openbmc/linux/drivers/net/ethernet/freescale/dpaa2/ |
H A D | dpaa2-ethtool.c | diff 2291982e29b1aa6e628d3072ef533aeb6299945f Tue Nov 29 08:12:19 CST 2022 Vladimir Oltean <vladimir.oltean@nxp.com> net: dpaa2-eth: serialize changes to priv->mac with a mutex
The dpaa2 architecture permits dynamic connections between objects on the fsl-mc bus, specifically between a DPNI object (represented by a struct net_device) and a DPMAC object (represented by a struct phylink).
The DPNI driver is notified when those connections are created/broken through the dpni_irq0_handler_thread() method. To ensure that ethtool operations, as well as netdev up/down operations serialize with the connection/disconnection of the DPNI with a DPMAC, dpni_irq0_handler_thread() takes the rtnl_lock() to block those other operations from taking place.
There is code called by dpaa2_mac_connect() which wants to acquire the rtnl_mutex once again, see phylink_create() -> phylink_register_sfp() -> sfp_bus_add_upstream() -> rtnl_lock(). So the strategy doesn't quite work out, even though it's fairly simple.
Create a different strategy, where all code paths in the dpaa2-eth driver access priv->mac only while they are holding priv->mac_lock. The phylink instance is not created or connected to the PHY under the priv->mac_lock, but only assigned to priv->mac then. This will eliminate the reliance on the rtnl_mutex.
Add lockdep annotations and put comments where holding the lock is not necessary, and priv->mac can be dereferenced freely.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Ioana Ciornei <ioana.ciornei@nxp.com> Tested-by: Ioana Ciornei <ioana.ciornei@nxp.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
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H A D | dpaa2-eth.h | diff 2291982e29b1aa6e628d3072ef533aeb6299945f Tue Nov 29 08:12:19 CST 2022 Vladimir Oltean <vladimir.oltean@nxp.com> net: dpaa2-eth: serialize changes to priv->mac with a mutex
The dpaa2 architecture permits dynamic connections between objects on the fsl-mc bus, specifically between a DPNI object (represented by a struct net_device) and a DPMAC object (represented by a struct phylink).
The DPNI driver is notified when those connections are created/broken through the dpni_irq0_handler_thread() method. To ensure that ethtool operations, as well as netdev up/down operations serialize with the connection/disconnection of the DPNI with a DPMAC, dpni_irq0_handler_thread() takes the rtnl_lock() to block those other operations from taking place.
There is code called by dpaa2_mac_connect() which wants to acquire the rtnl_mutex once again, see phylink_create() -> phylink_register_sfp() -> sfp_bus_add_upstream() -> rtnl_lock(). So the strategy doesn't quite work out, even though it's fairly simple.
Create a different strategy, where all code paths in the dpaa2-eth driver access priv->mac only while they are holding priv->mac_lock. The phylink instance is not created or connected to the PHY under the priv->mac_lock, but only assigned to priv->mac then. This will eliminate the reliance on the rtnl_mutex.
Add lockdep annotations and put comments where holding the lock is not necessary, and priv->mac can be dereferenced freely.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Ioana Ciornei <ioana.ciornei@nxp.com> Tested-by: Ioana Ciornei <ioana.ciornei@nxp.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
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H A D | dpaa2-eth.c | diff 2291982e29b1aa6e628d3072ef533aeb6299945f Tue Nov 29 08:12:19 CST 2022 Vladimir Oltean <vladimir.oltean@nxp.com> net: dpaa2-eth: serialize changes to priv->mac with a mutex
The dpaa2 architecture permits dynamic connections between objects on the fsl-mc bus, specifically between a DPNI object (represented by a struct net_device) and a DPMAC object (represented by a struct phylink).
The DPNI driver is notified when those connections are created/broken through the dpni_irq0_handler_thread() method. To ensure that ethtool operations, as well as netdev up/down operations serialize with the connection/disconnection of the DPNI with a DPMAC, dpni_irq0_handler_thread() takes the rtnl_lock() to block those other operations from taking place.
There is code called by dpaa2_mac_connect() which wants to acquire the rtnl_mutex once again, see phylink_create() -> phylink_register_sfp() -> sfp_bus_add_upstream() -> rtnl_lock(). So the strategy doesn't quite work out, even though it's fairly simple.
Create a different strategy, where all code paths in the dpaa2-eth driver access priv->mac only while they are holding priv->mac_lock. The phylink instance is not created or connected to the PHY under the priv->mac_lock, but only assigned to priv->mac then. This will eliminate the reliance on the rtnl_mutex.
Add lockdep annotations and put comments where holding the lock is not necessary, and priv->mac can be dereferenced freely.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Ioana Ciornei <ioana.ciornei@nxp.com> Tested-by: Ioana Ciornei <ioana.ciornei@nxp.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
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