x86/hyperv: Update 'struct hv_enlightened_vmcs' definition
authorVitaly Kuznetsov <vkuznets@redhat.com>
Tue, 30 Aug 2022 13:37:06 +0000 (15:37 +0200)
committerPaolo Bonzini <pbonzini@redhat.com>
Mon, 26 Sep 2022 16:02:37 +0000 (12:02 -0400)
commit5ef384a60f22f70a99b45f769144761de37b037c
treeab6325f3a7b75309e2f7f7d9b286c60b8264f47c
parentea9da788a61e47e7ab9cbad397453e51cd82ac0d
x86/hyperv: Update 'struct hv_enlightened_vmcs' definition

Updated Hyper-V Enlightened VMCS specification lists several new
fields for the following features:

- PerfGlobalCtrl
- EnclsExitingBitmap
- Tsc Scaling
- GuestLbrCtl
- CET
- SSP

Update the definition.

Note, the updated spec also provides an additional CPUID feature flag,
CPUIDD.0x4000000A.EBX BIT(0), for PerfGlobalCtrl to workaround a Windows
11 quirk.  Despite what the TLFS says:

  Indicates support for the GuestPerfGlobalCtrl and HostPerfGlobalCtrl
  fields in the enlightened VMCS.

guests can safely use the fields if they are enumerated in the
architectural VMX MSRs.  I.e. KVM-on-HyperV doesn't need to check the
CPUID bit, but KVM-as-HyperV must ensure the bit is set if PerfGlobalCtrl
fields are exposed to L1.

https://docs.microsoft.com/en-us/virtualization/hyper-v-on-windows/tlfs/tlfs

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
[sean: tweak CPUID name to make it PerfGlobalCtrl only]
Signed-off-by: Sean Christopherson <seanjc@google.com>
Acked-by: Wei Liu <wei.liu@kernel.org>
Link: https://lore.kernel.org/r/20220830133737.1539624-3-vkuznets@redhat.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
arch/x86/include/asm/hyperv-tlfs.h