CVE-2026-98692

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

thunderbolt: Make the DP tunnel activation callback mandatory

tb tunnel alloc dp() takes an optional callback which is run from dprx work once the DPRX capabilities read has completed. Without that callback tb dp dprx start() reads the capabilities synchronously and never queues the work. It however always takes a tunnel reference which is only dropped by dprx work itself or by tb dp dprx stop() when cancel delayed work() actually canceled that work. That reference is thus leaked for every tunnel without a callback.

The only tunnels without one are those from tb tunnel discover dp(), which are activated again when restoring from hibernation. Pass the callback to tb tunnel discover dp() as well and drop the synchronous path such that the DPRX capabilities are always read from dprx work. Hibernation restore then also no longer blocks for up to 12 seconds while waiting for that read to complete.

Also fix up the KUnit tests.