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By The Linux Camp News, October 15, 2026
The October 15 proposal would remove a manual boost opt-in on supporting CPPC systems. It changes the permitted performance range, not the hardware’s ability to deliver it.
On October 15, 2026, Huawei proposed enabling CPU boost by default in Linux’s generic ACPI CPPC CPUFreq driver. The trigger would be at least one possible CPU reporting boost support. The discussion retrieved on October 15 establishes a patch proposal, not a merged change or a kernel release operators can deploy. 3 2 1
CPPC stands for Collaborative Processor Performance Control. The generic driver is used on some ARM64 Linux servers, but this is not a proposal to change every CPU frequency driver. The existing behavior requires userspace to enable the sysfs boost option before using performance levels above the processor’s advertised nominal level. 1 3 2
The proposed initializer scans possible CPUs and reads their performance capabilities. A successful read with highest_perf greater than nominal_perf sets the driver’s boost_enabled flag and ends the search. Failed reads are skipped; without a qualifying CPU, the flag stays false. This happens before driver registration so the CPUFreq core can enable boost for each supporting policy, rather than assuming every CPU supports it. 3 2
For operators seeking the full advertised performance range, the benefit would be removing a manual opt-in, not adding hardware capability. An operational inference is that configurations relying on the disabled default deserve review if this patch is adopted: leaving boost untouched would no longer express the same performance restriction on supporting systems. 3
Arm’s Christian Loehle questioned whether a separate boost control remains useful, warning that it guarantees neither avoidance of throttling nor delivery of requested performance. He points operators needing platform- and workload-specific ceilings toward scaling_max_freq. That is reviewer guidance, not a tested tuning recipe: enabling boost should not be treated as evidence of a speedup or a thermal guarantee. 2 1