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> Windows > Why CPUID hypervisor flag is set? |
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bitRAKE 11 Aug 2021, 19:23
AMD documentation states it as reserved, but read as zero. Obviously, the hypervisor controls what is returned for CPUID and can set it to any value.
This article suggests that the value is not well defined: http://www.os2museum.com/wp/frequently-given-misleading-answers/ Maybe you could test from an EFI Shell to insure Windows is not doing something? _________________ ¯\(°_o)/¯ “languages are not safe - uses can be” Bjarne Stroustrup |
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11 Aug 2021, 19:23 |
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sinsi 11 Aug 2021, 21:06
If you have enabled Hyper-V in Windows, then even if you aren't using any VMs Windows runs as a special VM.
Quote: with virtualization enabled, the host OS also runs on top of the Hyper-V virtualization layer, just as guest operating systems do. https://docs.microsoft.com/en-us/virtualization/hyper-v-on-windows/about/ |
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11 Aug 2021, 21:06 |
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Feryno 20 Aug 2021, 05:11
then you can then ask hypervisor info by executing cpuid with input eax=40000000h and further
more info here: https://docs.microsoft.com/en-us/virtualization/hyper-v-on-windows/reference/tlfs |
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20 Aug 2021, 05:11 |
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