cpuid-dump should print hypervisor leaves (0x40000000)#349
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dlenski wants to merge 1 commit intopytorch:mainfrom
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cpuid-dump should print hypervisor leaves (0x40000000)#349dlenski wants to merge 1 commit intopytorch:mainfrom
dlenski wants to merge 1 commit intopytorch:mainfrom
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Per https://en.wikipedia.org/wiki/CPUID#EAX=4000'0000h-4FFFF'FFFh:_Reserved_for_Hypervisors: > CPUID leaves 40000000h to 4FFFFFFFh are not implemented in hardware, and > are reserved for use by hypervisors to provide hypervisor-specific > identification and feature information through this interception > mechanism. > > For leaf 40000000h, the hypervisor is expected to return the index of the > highest supported hypervisor CPUID leaf in EAX, and a 12-character > hypervisor ID string in EBX,ECX,EDX (in that order). For leaf 40000001h, > the hypervisor may return an interface identification signature in EAX - > e.g. hypervisors that wish to advertise that they are Hyper-V compatible > may return 0x31237648—"Hv#1" in EAX. For example, running with user-mode QEMU: ``` $ qemu-x86_64 cpuid-dump … CPUID 40000000: 40000001-54474354-43544743-47435447 [TCGTCGTCGTCG] CPUID 40000001: 00000000-00000000-00000000-00000000 … ``` Running under a recent version of WSL2 (Microsoft Hyper-V): ``` $ cpuid-dump … CPUID 40000000: 4000000B-7263694D-666F736F-76482074 [Microsoft Hv] CPUID 40000001: 31237648-00000000-00000000-00000000 [Hv#1] … CPUID 4000000B: 00000000-00000000-00000000-00000000 ```
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Per https://en.wikipedia.org/wiki/CPUID#EAX=4000'0000h-4FFFF'FFFh:_Reserved_for_Hypervisors:
For example, running with user-mode QEMU:
Running under a recent version of WSL2 (Microsoft Hyper-V):