| Message ID | 509439ff3e756ea1dade2738e305f08fc7920650.1491220439.git.nsekhar@ti.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
From: Sekhar Nori <nsekhar@ti.com> Date: Mon, 3 Apr 2017 17:34:28 +0530 > TI's cpsw driver handles both OF and non-OF case for phy > connect. Unfortunately of_phy_connect() returns NULL on > error while phy_connect() returns ERR_PTR(). > > To handle this, cpsw_slave_open() overrides the return value > from phy_connect() to make it NULL or error. > > This leaves a small window, where cpsw_adjust_link() may be > invoked for a slave while slave->phy pointer is temporarily > set to -ENODEV (or some other error) before it is finally set > to NULL. > > _cpsw_adjust_link() only handles the NULL case, and an oops > results when ERR_PTR() is seen by it. > > Note that cpsw_adjust_link() checks PHY status for each > slave whenever it is invoked. It can so happen that even > though phy_connect() for a given slave returns error, > _cpsw_adjust_link() is still called for that slave because > the link status of another slave changed. > > Fix this by using a temporary pointer to store return value > of {of_}phy_connect() and do a one-time write to slave->phy. > > Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com> > Reported-by: Yan Liu <yan-liu@ti.com> > Signed-off-by: Sekhar Nori <nsekhar@ti.com> Applied, thank you. -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/net/ethernet/ti/cpsw.c b/drivers/net/ethernet/ti/cpsw.c index 9f3d9c67e3fe..5a4faa4489d0 100644 --- a/drivers/net/ethernet/ti/cpsw.c +++ b/drivers/net/ethernet/ti/cpsw.c @@ -1267,6 +1267,7 @@ static void soft_reset_slave(struct cpsw_slave *slave) static void cpsw_slave_open(struct cpsw_slave *slave, struct cpsw_priv *priv) { u32 slave_port; + struct phy_device *phy; struct cpsw_common *cpsw = priv->cpsw; soft_reset_slave(slave); @@ -1300,27 +1301,28 @@ static void cpsw_slave_open(struct cpsw_slave *slave, struct cpsw_priv *priv) 1 << slave_port, 0, 0, ALE_MCAST_FWD_2); if (slave->data->phy_node) { - slave->phy = of_phy_connect(priv->ndev, slave->data->phy_node, + phy = of_phy_connect(priv->ndev, slave->data->phy_node, &cpsw_adjust_link, 0, slave->data->phy_if); - if (!slave->phy) { + if (!phy) { dev_err(priv->dev, "phy \"%s\" not found on slave %d\n", slave->data->phy_node->full_name, slave->slave_num); return; } } else { - slave->phy = phy_connect(priv->ndev, slave->data->phy_id, + phy = phy_connect(priv->ndev, slave->data->phy_id, &cpsw_adjust_link, slave->data->phy_if); - if (IS_ERR(slave->phy)) { + if (IS_ERR(phy)) { dev_err(priv->dev, "phy \"%s\" not found on slave %d, err %ld\n", slave->data->phy_id, slave->slave_num, - PTR_ERR(slave->phy)); - slave->phy = NULL; + PTR_ERR(phy)); return; } } + slave->phy = phy; + phy_attached_info(slave->phy); phy_start(slave->phy);
TI's cpsw driver handles both OF and non-OF case for phy connect. Unfortunately of_phy_connect() returns NULL on error while phy_connect() returns ERR_PTR(). To handle this, cpsw_slave_open() overrides the return value from phy_connect() to make it NULL or error. This leaves a small window, where cpsw_adjust_link() may be invoked for a slave while slave->phy pointer is temporarily set to -ENODEV (or some other error) before it is finally set to NULL. _cpsw_adjust_link() only handles the NULL case, and an oops results when ERR_PTR() is seen by it. Note that cpsw_adjust_link() checks PHY status for each slave whenever it is invoked. It can so happen that even though phy_connect() for a given slave returns error, _cpsw_adjust_link() is still called for that slave because the link status of another slave changed. Fix this by using a temporary pointer to store return value of {of_}phy_connect() and do a one-time write to slave->phy. Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com> Reported-by: Yan Liu <yan-liu@ti.com> Signed-off-by: Sekhar Nori <nsekhar@ti.com> --- drivers/net/ethernet/ti/cpsw.c | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-)