Linux 6.11 Upstream Now Defaults To A Better SATA Link Power Management Policy

It's not too often that the ATA pull request for a new Linux kernel merge window has much worth mentioning. With Linux 6.11 there is a change to the kernel defaults worth noting over the default SATA link power management policy. In this case most Linux distributions have been setting a better default themselves and is now a case of the upstream kernel defaults catching up.

The Linux kernel CONFIG_SATA_MOBILE_LPM_POLICY option is used for setting the default SATA link power management policy whether it be for sticking to firmware settings, maximum performance, medium power, or minimum power use. The Linux kernel has long defaulted to the "keep firmware settings" option while most Linux distribution vendor kernels have opted for the medium power mode. With Linux 6.11, the upstream kernel is defaulting to the medium power mode with the "med_power_with_dipm" option.

The Linux kernel default previously stuck to using the "keep firmware settings" as the SATA link power management policy since changing the link power management (LPM) could break SATA hot-plugging support. But since then the Linux kernel has changed so that any external SATA ports are treated as to always keep their firmware settings.

In practice this change won't mean much for those sticking close to distribution vendor kernel configurations, but for those spinning their own kernels or otherwise sticking close to the upstream kernel defaults, this change can help enhance the SATA power management... That is if you are still relying on SATA drives.

That's about it for the ATA pull of changes for Linux 6.11.