Re: [PATCH net 1/2] net: phy: Avoid NPD upon phy_detach() when driver is unbound

[Andrew Lunn]

On Wed, Sep 16, 2020 at 08:43:09PM -0700, Florian Fainelli wrote:
> If we have unbound the PHY driver prior to calling phy_detach() (often
> via phy_disconnect()) then we can cause a NULL pointer de-reference
> accessing the driver owner member. The steps to reproduce are:
> 
> echo unimac-mdio-0:01 > /sys/class/net/eth0/phydev/driver/unbind
> ip link set eth0 down

Hi Florian

How forceful is this unbind? Can we actually block it while the
interface is up? Or returning -EBUSY would make sense.

          Andrew