When doing "ip link set dev ... up" for a ksz9477 backed link, ksz9477_phy_setup is called and it calls phy_remove_link_mode to remove 1000baseT HDX. During phy_remove_link_mode, phy_advertise_supported is called. Doing so reverts any previous change to advertised link modes e.g. using a udevd .link file.
phy_remove_link_mode is not meant to be used while opening a link and should be called during phy probe when the link is not yet available to userspace. Therefore move the phy_remove_link_mode calls into ksz9477_switch_register. It indirectly calls dsa_register_switch, which creates the relevant struct phy_devices and we update the link modes right after that. At that time dev->features is already initialized by ksz9477_switch_detect. Remove phy_setup from ksz_dev_ops as no users remain. Link: https://lore.kernel.org/netdev/20200715192722.gd1256...@lunn.ch/ Fixes: 42fc6a4c613019 ("net: dsa: microchip: prepare PHY for proper advertisement") Signed-off-by: Helmut Grohne <helmut.gro...@intenta.de> --- drivers/net/dsa/microchip/ksz9477.c | 42 ++++++++++++++------------ drivers/net/dsa/microchip/ksz_common.c | 2 -- drivers/net/dsa/microchip/ksz_common.h | 2 -- 3 files changed, 23 insertions(+), 23 deletions(-) As Andrew Lunn indicated, my patch introduces a null pointer dereference when PHYs are missing from the device tree. I was able to reproduce the failure mode and this version fixes it. Helmut changes since v3: * Check dsa_is_user_port. Thanks to Andrew Lunn. changes since v2: * Operate on the correct phydev. Thanks to Andrew Lunn. changes since v1: * Don't change phy_remove_link_mode. Instead, call it at the right time. Thanks to Andrew Lunn for the detailed explanation. diff --git a/drivers/net/dsa/microchip/ksz9477.c b/drivers/net/dsa/microchip/ksz9477.c index 8d15c3016024..4a9239b2c2e4 100644 --- a/drivers/net/dsa/microchip/ksz9477.c +++ b/drivers/net/dsa/microchip/ksz9477.c @@ -974,23 +974,6 @@ static void ksz9477_port_mirror_del(struct dsa_switch *ds, int port, PORT_MIRROR_SNIFFER, false); } -static void ksz9477_phy_setup(struct ksz_device *dev, int port, - struct phy_device *phy) -{ - /* Only apply to port with PHY. */ - if (port >= dev->phy_port_cnt) - return; - - /* The MAC actually cannot run in 1000 half-duplex mode. */ - phy_remove_link_mode(phy, - ETHTOOL_LINK_MODE_1000baseT_Half_BIT); - - /* PHY does not support gigabit. */ - if (!(dev->features & GBIT_SUPPORT)) - phy_remove_link_mode(phy, - ETHTOOL_LINK_MODE_1000baseT_Full_BIT); -} - static bool ksz9477_get_gbit(struct ksz_device *dev, u8 data) { bool gbit; @@ -1603,7 +1586,6 @@ static const struct ksz_dev_ops ksz9477_dev_ops = { .get_port_addr = ksz9477_get_port_addr, .cfg_port_member = ksz9477_cfg_port_member, .flush_dyn_mac_table = ksz9477_flush_dyn_mac_table, - .phy_setup = ksz9477_phy_setup, .port_setup = ksz9477_port_setup, .r_mib_cnt = ksz9477_r_mib_cnt, .r_mib_pkt = ksz9477_r_mib_pkt, @@ -1617,7 +1599,29 @@ static const struct ksz_dev_ops ksz9477_dev_ops = { int ksz9477_switch_register(struct ksz_device *dev) { - return ksz_switch_register(dev, &ksz9477_dev_ops); + int ret, i; + struct phy_device *phydev; + + ret = ksz_switch_register(dev, &ksz9477_dev_ops); + if (ret) + return ret; + + for (i = 0; i < dev->phy_port_cnt; ++i) { + if (!dsa_is_user_port(dev->ds, i)) + continue; + + phydev = dsa_to_port(dev->ds, i)->slave->phydev; + + /* The MAC actually cannot run in 1000 half-duplex mode. */ + phy_remove_link_mode(phydev, + ETHTOOL_LINK_MODE_1000baseT_Half_BIT); + + /* PHY does not support gigabit. */ + if (!(dev->features & GBIT_SUPPORT)) + phy_remove_link_mode(phydev, + ETHTOOL_LINK_MODE_1000baseT_Full_BIT); + } + return ret; } EXPORT_SYMBOL(ksz9477_switch_register); diff --git a/drivers/net/dsa/microchip/ksz_common.c b/drivers/net/dsa/microchip/ksz_common.c index fd1d6676ae4f..7b6c0dce7536 100644 --- a/drivers/net/dsa/microchip/ksz_common.c +++ b/drivers/net/dsa/microchip/ksz_common.c @@ -358,8 +358,6 @@ int ksz_enable_port(struct dsa_switch *ds, int port, struct phy_device *phy) /* setup slave port */ dev->dev_ops->port_setup(dev, port, false); - if (dev->dev_ops->phy_setup) - dev->dev_ops->phy_setup(dev, port, phy); /* port_stp_state_set() will be called after to enable the port so * there is no need to do anything. diff --git a/drivers/net/dsa/microchip/ksz_common.h b/drivers/net/dsa/microchip/ksz_common.h index f2c9bb68fd33..7d11dd32ec0d 100644 --- a/drivers/net/dsa/microchip/ksz_common.h +++ b/drivers/net/dsa/microchip/ksz_common.h @@ -119,8 +119,6 @@ struct ksz_dev_ops { u32 (*get_port_addr)(int port, int offset); void (*cfg_port_member)(struct ksz_device *dev, int port, u8 member); void (*flush_dyn_mac_table)(struct ksz_device *dev, int port); - void (*phy_setup)(struct ksz_device *dev, int port, - struct phy_device *phy); void (*port_cleanup)(struct ksz_device *dev, int port); void (*port_setup)(struct ksz_device *dev, int port, bool cpu_port); void (*r_phy)(struct ksz_device *dev, u16 phy, u16 reg, u16 *val); -- 2.20.1
