Intel now comes with a new ACPI specification called Platform Firmware Runtime Update and Telemetry (PFRUT). This allows for firmware updates to a PC’s BIOS or UEFI without forcing a reboot. This comes has a blessing for those who wish not to reboot the devices.The feature is Linux-only, at least for now. Windows users have to wait to get it.
Intel’s been working on PFRUT for some time, previously under the moniker Seamless Update. The idea is to reduce downtime, especially for servers that should ideally remain available 100 percent of the time. Servers can undergo BIOS/UEFI updates on the fly, keeping critical workloads fully operational the whole time.
The upcoming “pfr_update” driver is set to be introduced in Linux kernel 5.17. It appears to be designed for system firmware updates in cases of critical bugs or security issues, allowing server administrators to patch their hardware without downtime.
The current BIOS/UEFI update procedure requires the OS to upload the new firmware to the BIOS. On reboot, the firmware gets handed off to the motherboard to “flash” the BIOS or UEFI. Under the PFRUT driver set, the update is handled entirely by the OS, without restarting the computer.
Currently the driver update is in the “linux-next” branch. That means it should be in the next stable kernel cycle, coming sometime in mid-January and it is a “server-exclusive” feature. That means it may or may not be included in consumer Linux distributions. It might get incorporated due to its open source projet nature.
This is a Linux-only capability,PFRUT is a feature included in the ACPI power management specification, so it could arrive on Windows and other desktop PCs in the future.