The Linux Kernel 7.2 delivers a comprehensive set of updates that significantly enhance system stability, security, and performance. The focus of this release was on implementing new security mechanisms alongside deep optimizations for core components such as file systems and memory management.
A central aspect of the update is the enhancement of system security through the integration of the Rust library 'zerocopy'. This integration involves approximately 39,000 lines of code designed to eliminate unsafe operations during memory manipulation, thereby closing potential security vulnerabilities. Compatibility with Rust 1.98 and the software-based Kernel Address Sanitizer is also ensured.
Significant progress was made in the file system domain, particularly for Btrfs. The system now allows for the automatic activation of large folios and introduces huge folios up to 2 Megabytes. These extensions improve stability and the handling of large data volumes, while better management of direct I/O and optimized bio size limits for sequential writes lead to higher throughput.
The performance optimizations also extend to internal kernel mechanisms. A substantial improvement was achieved for the performance of anonymous and unnamed pipes. The update resolves a bottleneck where memory allocation previously held critical locks, which could cause system stalls. By implementing a new method to pre-allocate resources outside of the lock and efficiently recycle leftover pages, throughput is massively increased, and latency is reduced, especially under high memory pressure.
Regarding hardware support, important adjustments were made to power management. Kernel 7.2 offers new CPUFreq scaling support for modern chipsets like Qualcomm Shikra, along with improved thermal monitoring. Conversely, older hardware components, such as drivers for AMD Elan SoCs and i486 CPUs, are being deprecated and removed, future-proofing the system architecture. Furthermore, LZ4 compression options for hibernation are introduced, and ACPI standards are updated.