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So, we >> use a CPU vendor specific check to approximate that the chipset is >> recent and not affected by the bug? If so, is there no better way to >> check for a newer chipset than this? > > So I did some git archeology but that particular addition is in some > conglomerate, glued-together patch from 2007 which added the cpuidle > tree: > > commit 4f86d3a8e297205780cca027e974fd5f81064780 > Author: Len Brown > Date: Wed Oct 3 18:58:00 2007 -0400 > > cpuidle: consolidate 2.6.22 cpuidle branch into one patch > > > so the most precise check here should be to limit that dummy read to > that Intel chipset which needed it. Damned if I knew how to figure out > which... > Functionally most Intel platforms use intel_idle though these days though, right?