Re: [PATCH NET v3 1/2] net: phy: Add phy loopback support in net phy framework

Hi, Andrew

On 2017/6/24 11:12, Andrew Lunn wrote:

quoted

+int phy_loopback(struct phy_device *phydev, bool enable)
+{
+	struct phy_driver *phydrv = to_phy_driver(phydev->mdio.dev.driver);
+	int ret = 0;
+
+	if (enable && phydev->loopback_enabled)
+		return -EBUSY;
+
+	if (!enable && !phydev->loopback_enabled)
+		return -EINVAL;
+
+	if (phydev->drv && phydrv->set_loopback)
+		ret = phydrv->set_loopback(phydev, enable);

   	else
		ret = -EOPNOTSUPP;

quoted

+
+	if (ret)
+		return ret;
+
+	phydev->loopback_enabled = enable;
+
+	return 0;
+}
+EXPORT_SYMBOL(phy_loopback);

One of the comments we made of the PHY code in the hns driver is that
its locking is completely broken. You have made the same error
here. The core needs to hold the mutex while calling into the PHY
driver.

Do you mean hns_nic_config_phy_loopback need to hold the mutex while
calling phy_loopback? and other place that calling phy_* function?

Best Regards
Yunsheng Lin