Zstd Compressed Firmware Submitted For Linux 5.19, Other Driver Core Changes

Greg Kroah-Hartman has gotten onto submitting his feature pull requests to Linux 5.19 for various areas of the kernel he oversees. With the driver core changes with this new kernel is now the ability to compress firmware files using the popular Zstd.

For years there has been proposed patches for adding support for Zstd compression to the Linux kernel's firmware handling in order to save disk space while offering speedy decompression and as an alternative to the likes of the existing XZ compression. Those patches never made it over the finish line while finally with Linux 5.19 it is going to be in place.

As reported back in April, Zstd compressed firmware is finally happening for those wanting to use the Zstandard compression algorithm developed by Facebook. Zstd-compressed firmware should help in saving measurable amounts of disk space while still offering speedy decompression that is done dynamically by the kernel. Firmware files ending in .zst will be decompressed by the Linux kernel's firmware loader.

Another notable driver core change with Linux 5.19 is user-space able to initiate firmware updates via sysfs. This is an Intel-led change motivated by the need to easily allow firmware updates of their FPGA PCIe cards. To this point firmware updates were initiated just by the kernel space while now via this adaptable sysfs interface it makes it easier for user-space to initiate said updates when needed.

A third useful addition with this pull is the ability to report a device's physical location on the system such as a particular port for being particularly help when having multiple of the same devices connected to the system. Some devices expose physical locations via ACPI already while more buses are expected to be able to expose physical location properties moving ahead.

See this morning's pull request for the complete list of driver core changes for Linux 5.19.