Re: [PATCH] x86/idle: Mark "idle=poll" as deprecated

[Borislav Petkov]

On Sun, Jan 18, 2026 at 06:10:09PM -0500, Aaron Tomlin wrote:
> The "idle=poll" boot parameter is a blunt instrument that forces all
> CPUs in the system into a continuous "polling" state. While effective
> at eliminating wake-up latency, this global override is architecturally
> obsolete and inefficient on modern multicore systems.

Nope.

It is still very useful when you want to stop the machine from entering sleep
states.

> By writing special value "n/a" to the per-CPU sysfs node
> /sys/devices/system/cpu/cpuN/power/pm_qos_resume_latency_us, userspace
> can force a specific CPU to poll without imposing this cost globally.

You can't do that on the kernel command line and thus prevent entering sleep
states from the get-go.

So no, it ain't broke so no need to fix it.

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette