Linux Kernel 6.15: Rust Integration, Performance Boosts, and Expanded Hardware Support

The latest iteration of the Linux kernel, version 6.15, has officially arrived, bringing a wealth of improvements, new features, and expanded hardware support to the open-source world. This release is particularly significant due to its advancements in file system performance, especially for exFAT, as well as its deeper integration of the Rust programming language for enhanced security and modernity.

Rust's Growing Presence

One of the most exciting aspects of Linux 6.15 is the introduction of the first Rust-written Direct Rendering Manager (DRM) driver, dubbed NOVA. This driver targets NVIDIA RTX 2000 "Turing" series and newer GPUs.

Written entirely in Rust, NOVA aims to succeed the existing Nouveau driver, paving the way for memory-safe kernel development. Furthermore, Rust support extends to hrtimer and ARMv7, showcasing a commitment to leveraging Rust's safety guarantees in essential kernel subsystems. This shift should reduce memory safety vulnerabilities often associated with low-level system software.

ExFAT Performance Revolutionized

Perhaps one of the most user-noticeable changes is the dramatic improvements to file system operations, with exFAT receiving a massive speed boost. According to reports, deleting large files on exFAT is now up to 150 times faster. Deleting an 80GB file with the discard mount option now takes a mere 1.6 seconds, compared to over 4 minutes in previous versions. This is achieved through optimized cluster discarding algorithms.

Key File System Enhancements:

• Btrfs: Now supports fast and real-time zstd compression levels (-15 to -1), which improves speed with reasonable compression ratios.
• FUSE: Can handle file names longer than 1024 characters and enforce timeouts on unresponsive user-space servers, enhancing stability.
• bcachefs: Gains case-insensitivity support and new 'scrub' functionality for error detection and repair.

Networking Improvements

Linux 6.15 also sees advancements in networking, including zero-copy receive (zcrx) via the io_uring subsystem. This allows network packet data to flow directly into userspace memory, minimizing overhead from kernel-to-user copying and circumventing traditional alignment requirements. Another networking enhancement is the addition of the TCP_RTO_MAX_MS socket option, giving users more precise control over TCP retransmission timeouts.

Expanded Hardware Support

Kernel 6.15 enriches hardware compatibility, featuring:

• Dedicated drivers for the Apple Touch Bar on both Intel and Apple M1/M2 MacBook Pros, including backlight, touch interaction, and function key display support.
• New Samsung GalaxyBook drivers offering full ACPI platform support, battery management, and function key handling.
• Improved support for Sony PlayStation 5, Xbox, and Turtle Beach game controllers, as well as new drivers for racing and flight simulator devices.
• Support for Intel Killer E5000 Ethernet controllers.

In addition, Linux 6.15 introduces a new fwctl subsystem for standardized firmware RPCs and a new fanotify API for real-time mount/unmount event monitoring, plus support for hardware-encrypted keys in the block layer. These features collectively contribute to a more versatile and secure computing environment.

From groundbreaking language integrations to notable file system performance improvements and extensive hardware support, Linux 6.15 is poised to deliver a more robust and faster Linux experience.

What are your thoughts on the changes in Linux 6.15? Share your opinions and experiences in the comments below!

• Kernel
• Linux
• Rust