CVE-2026-53231

In the Linux kernel, the following vulnerability has been resolved:

net: phy: don't try to setup PHY-driven SFP cages when using genphy

We don't have support for PHY-driver SFP cages with the genphy code.

On top of that, it was found by sashiko that running sfp_bus_add_upstream() for genphy deadlocks, as for genphy the PHY probing runs under RTNL, which isn't the case for non-genphy drivers.

This problem was reproduced, and does lead to a deadlock on RTNL.

Before the blamed commit, the phy_sfp_probe() call was made by individual PHY drivers, so there was no way to get to the SFP probing path when using genphy.

Let's therefore only run phy_sfp_probe when not using genphy.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.