Thunderbolt Updates Head Into Linux 4.17, Adds USB/SL4 Security Level
Thunderbolt changes queued for Linux 4.17 include support for the new Intel Titan Ridge controller, support for a USB-only SL4 security level, prevent crashes when the ICM firmware is not active, support for a pre-boot ACL, handling for rejected Thunderbolt devices, and other error handling improvements and Thunderbolt related fixes.
The SL4/USB-only Thunderbolt option is part of the ongoing Thunderbolt security level work for allowing the user to restrict the access rights of Thunderbolt devices connected to a system. On the desktop side it's being wired up through Red Hat's Bolt project and now there is the "SL4" security level where only USB support would be allowed to the connected device(s).
There are also NVMEM updates, hardware tracing driver updates, Parport updates, and other changes as outlined in full via the char/misc pull request.