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charset=UTF-8 Content-Transfer-Encoding: 7bit On 11/6/24 00:14, Artem Bityutskiy wrote: > The non-architectural part of it is basically this. > > The algorithm assumes that in the sub-state part of the mwait hint (4 least > significant bits) always starts with 0 and then next sub-state is always 1, and > there are no gaps. This is not documented in Intel SDM. This happens to work on > majority of Intel platforms, but this is not architectural. I wouldn't call that a "non-architectural algorithm". It's a bug, plain and simple.