On 9/22/22 10:48, Limonciello, Mario wrote: > > 2) The title says to limit it to old intel systems, but nothing about this actually enforces that. > It actually is limited to all Intel systems, but effectively won't be used on anything but new > ones because of intel_idle. > > As an idea for #2 you could check for CONFIG_INTEL_IDLE in the Intel case and > if it's not defined show a pr_notice_once() type of message trying to tell people to use > Intel Idle instead for better performance. What does that have to do with *this* patch, though? If you've got CONFIG_INTEL_IDLE disabled, you'll be slow before this patch. You'll also be slow after this patch. It's entirely orthogonal. I can add a "Practically" to the subject so folks don't confuse it with some hard limit that is being enforced: ACPI: processor idle: Practically limit "Dummy wait" workaround to old Intel systems BTW, is there seriously a strong technical reason that AMD systems are still using this code? Or is it pure inertia?