Linux USB4STREAM Lands in Kernel 7.2: Raw Data Streams Over Thunderbolt, No Network Needed
Linux USB4STREAM Lands in Kernel 7.2: Raw Data Streams Over Thunderbolt, No Network Needed
Publish Date: 2026-06-23 09:18:00
Source Domain: www.techtimes.com
On June 22, 2026, Intel’s USB4STREAM protocol — a new mechanism for sending raw data directly between two machines over a USB4 or Thunderbolt cable — was merged into the official Linux 7.2 kernel tree by Linus Torvalds, with no objections raised during the merge window review. Any developer with a USB4 or Thunderbolt port and Linux 7.2 can now stream data between machines at up to 40–80 Gbps without configuring a network interface, without the IP stack, and without modifying a single existing application.
The merge completes a development arc that Intel Thunderbolt maintainer Mika Westerberg and fellow Intel engineer Alan Borzeszkowski began in early May 2026 when they sent the first USB4STREAM patches for public review. The driver was merged without objection as part of a broader USB/Thunderbolt pull request submitted by subsystem maintainer Greg Kroah-Hartman.
What USB4STREAM Is, and What It Is Not
USB4STREAM is not a faster version of Thunderbolt networking. That already exists: the thunderbolt_net driver has been in the Linux kernel for years, creating a virtual Ethernet interface over Thunderbolt cable connections and delivering around 13–14 Gbps of real-world throughput over a 40 Gbps hardware link. USB4STREAM is a categorically different abstraction. Instead of creating a network interface, it creates a character device at /dev/tbstreamX — a Unix file-like interface that applications open with standard open(), read with read(), and write with write() system calls.
The practical difference is architectural: a Thunderbolt networking connection requires IP addresses, network configuration, and a software stack that imposes framing overhead. A USB4STREAM connection requires neither. Two machines, one cable, one dd command.
Any Read-Write App Works: The Unix Device Philosophy at 40 Gbps
Because USB4STREAM exposes a character device — the same abstraction that Linux uses for serial ports, sound cards, and frame buffers — every Unix application that…
