Key Power Management Fixes Arrive in Linux 7.1 The Linux kernel’s power management subsystem has received a series of critical updates for both AMD and Intel platforms, addressing essential issues to improve the reliability of power management functions directly impacting laptop battery life. The updates, finalized for integration into the mainline on May 22, 2026, focus particularly on AMD’s Dynamic EPP functionality and fixes related to Intel’s new Bartlett Lake processors.

Significant Design Changes to AMD P-State Driver’s Dynamic EPP One of the most noteworthy updates involves modifications to the handling of the Dynamic EPP (Dynamic Energy Performance Preference) feature in the AMD P-State driver.

Dynamic EPP enables AMD Ryzen-powered laptops to automatically switch between different performance profiles based on whether they are plugged into an AC power source or running on battery. Specifically, the system dynamically adjusts EPP values by evaluating multiple factors like power state, plug/unplug events, and ACPI Platform Profiles. This allows the kernel to autonomously ensure high performance when connected to power and reduced energy consumption during battery use. However, this feature, introduced during Linux 7.1’s merge window, faced multiple bug reports early on. As a result, the development team decided to make significant changes to how Dynamic EPP is implemented. Previously, Dynamic EPP could be enabled during the kernel build phase as a Kconfig option. With the latest update, this option has been removed from Kconfig, and users must explicitly enable it at boot time by using the module parameter amd_pstate=dynamic_epp=1. This shift means users must consciously activate the feature during system startup rather than during kernel compilation. The change was made to avoid the risks associated with enabling the feature by default, especially in a state where bugs might still persist. If left as a build-time option, distributions could inadvertently activate it in their default settings. Switching to a module parameter ensures that only users testing the feature can opt-in, thereby minimizing potential instability. In addition to this procedural change, several bug fixes have been applied directly to the Dynamic EPP code. Improvements include refining the control logic for how the kernel autonomously adjusts EPP modes and implementing measures to block manual EPP writes to the AMD P-State driver. The development community remains optimistic that the Dynamic EPP feature will achieve sufficient stability to be enabled by default in the future. However, no specific timeline for this has been provided as of now.

Fixing the 7GHz Misreporting Issue for Intel Bartlett Lake Intel has also addressed a critical issue affecting its P-State driver on the newly introduced Bartlett Lake platform. In processors featuring only Performance cores (P-cores), the driver was incorrectly reporting clock frequencies as 7GHz—a figure that is technically unachievable. Bartlett Lake is one of Intel’s latest platforms, featuring processors with P-core-only configurations. On these chips, the Intel P-State driver miscalculated scaling factors and reported the erroneous clock frequency to the system. This issue not only displayed incorrect values in frequency monitoring tools like CPUFreq but also had the potential to disrupt power management logic. If the system recognized the CPU as operating at 7GHz, it might set inappropriate voltage and frequency control parameters, leading to inefficiencies. The timing of this fix is notable. Initially, the Bartlett Lake scaling factor adjustment was scheduled for the Linux 7.2 development cycle. However, due to the severity of the issue, it was prioritized for inclusion in Linux 7.1. By addressing the problem before the stable kernel release, the development team ensured that Bartlett Lake users would not experience the issue.

Concurrent Fix for Raptor Lake E CPU Scaling Alongside the Bartlett Lake adjustment, another scaling issue was resolved in the Intel P-State driver concerning Raptor Lake E CPUs. These processors, part of Intel’s 13th-generation Core lineup, also faced incorrect scaling factors, which hindered accurate reporting of clock frequencies and potentially disrupted power management operations. The Intel P-State driver is a critical component for managing CPU frequency scaling and power states across Intel platforms. Its scaling factor converts internal hardware frequency register values into the actual clock speeds visible to user-space tools. Errors in these calculations can lead to discrepancies between reported and actual operating frequencies, reducing the precision of power management.

Future Outlook for Power Management in Linux 7.1 These updates aim to tackle pressing issues in the Linux kernel’s power management subsystem, addressing problems specific to AMD and Intel platforms. The fixes significantly enhance the quality of the Linux 7.1 release. For laptop users, improved power management precision directly impacts battery life and system responsiveness. Stability in AMD’s Dynamic EPP functionality and accurate frequency management in Intel’s new and existing processors promise substantial benefits. Since these fixes are already merged into the Linux kernel’s mainline branch, distributions are expected to incorporate them in upcoming updates, making them available to end-users soon.