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Date: Mon, 23 Jul 2018 10:28:41 +0100
From: Alan Cox <gnomes@lxorguk.ukuu.org.uk>
Subject: Re: [PATCH v14 20/25] x86/tsc: calibrate tsc only once
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> >> If we determined tsc early in boot using one of the quick methods:
> >> from cpuid/msr/quick_pit, can we assume that frequencies of all other
> >> CPUs will be determined the same way? Or do we still have to fallback

Not on 32bit at least. You can have a mixed slot 1 SMP system such as
an ASUS BP6 with cores at say 300 and 450MHz.

Now whether you'll find any such system in the world today is another
question.

Alan