Re: [PATCH net v3 2/5] net: phy: unregister SFP upstream before port cleanup

[Andrew Lunn <andrew@lunn.ch>]

On Wed, Aug 19, 2026 at 02:02:33PM +0800, Xuanqiang Luo wrote:
> From: Xuanqiang Luo <luoxuanqiang@kylinos.cn>
> 
> Commit 4497f5028675 ("net: phy: Clean the phy_ports after unregistering
> the downstream SFP bus") established that an SFP upstream must be
> unregistered before its phy_ports are destroyed because SFP callbacks
> may access these ports.
> 
> phy_setup_ports() does not follow this order when a later port setup
> step fails after phy_sfp_probe() succeeds. It destroys the SFP phy_port
> and leaves phy_probe() to unregister the upstream later, creating a race
> between port destruction and SFP upstream callbacks.
> 
> The error unwind is also split across three functions. If
> phy_setup_sfp_port() fails, phy_sfp_probe() leaves the upstream
> registered and relies on phy_probe() to remove it after
> phy_setup_ports() returns.
> 
> Make each layer unwind the resources it successfully set up. Unregister
> only the upstream in phy_sfp_probe() when SFP port setup fails, since
> the failed port has already been destroyed. Add phy_sfp_release() for a
> successful SFP probe, and make phy_setup_ports() use it before cleaning
> up the remaining ports. Once phy_setup_ports() has rolled back all port
> setup, make phy_probe() skip this cleanup.
> 
> Fixes: 589e934d2735 ("net: phy: Introduce PHY ports representation")
> Signed-off-by: Xuanqiang Luo <luoxuanqiang@kylinos.cn>

Reviewed-by: Andrew Lunn <andrew@lunn.ch>

    Andrew