| From | Thomas Gleixner <> | Subject | Re: [PATCH 0/2] RFC: Precise TSC migration | Date | Tue, 01 Dec 2020 14:48:11 +0100 |
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On Mon, Nov 30 2020 at 16:16, Marcelo Tosatti wrote: >> Besides, Linux guests don't sync the TSC via IA32_TSC write, >> but rather use IA32_TSC_ADJUST which currently doesn't participate >> in the tsc sync heruistics. > > Linux should not try to sync the TSC with IA32_TSC_ADJUST. It expects > the BIOS to boot with synced TSCs.
That's wishful thinking.
Reality is that BIOS tinkerers fail to get it right. TSC_ADJUST allows us to undo the wreckage they create.
Thanks,
tglx
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