Linus Torvalds announced the stabilization of version 5.9.
Among other changes, he introduced support for FSGSBASE in the 5.9 kernel, which should improve context switching performance on AMD and Intel processors. FSGSBASE allows you to read and modify the contents of the FS/GS registers from user space, which should improve overall performance after the Specter/Metldown vulnerabilities were closed. The support itself was added by Microsoft engineers a few years ago.
Same:
- Added support for Radeon RX 6000 "RDNA 2"
- added support for NVMe drive zoning commands (NVMe zoned namespaces (ZNS))
- initial support for IBM Power10
- various improvements to the storage subsystem, tightened protection against the use of GPL layers for linking proprietary drivers with kernel components
- the energy consumption model (Energy Model framework) now describes not only the behavior of the energy consumption of the CPU, but also of peripheral devices
- REJECT added to Netfilter at the PREROUTING stage
- for AMD Zen and newer CPU models, support for P2PDMA technology has been added, which allows using DMA for direct data transfer between the memory of two devices connected to the PCI bus.
Source: linux.org.ru