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x86/hyperv: Update 'struct hv_enlightened_vmcs' definition

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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>
This commit is contained in:
Vitaly Kuznetsov 2022-08-30 15:37:06 +02:00 committed by Paolo Bonzini
parent ea9da788a6
commit 5ef384a60f
1 changed files with 16 additions and 2 deletions
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18
arch/x86/include/asm/hyperv-tlfs.h
View File

@ -138,6 +138,9 @@
#define HV_X64_NESTED_GUEST_MAPPING_FLUSH BIT(18)
#define HV_X64_NESTED_MSR_BITMAP BIT(19)
/* Nested features #2. These are HYPERV_CPUID_NESTED_FEATURES.EBX bits. */
#define HV_X64_NESTED_EVMCS1_PERF_GLOBAL_CTRL BIT(0)
/*
* This is specific to AMD and specifies that enlightened TLB flush is
* supported. If guest opts in to this feature, ASID invalidations only
@ -559,9 +562,20 @@ struct hv_enlightened_vmcs {
u64 partition_assist_page;
u64 padding64_4[4];
u64 guest_bndcfgs;
u64 padding64_5[7];
u64 guest_ia32_perf_global_ctrl;
u64 guest_ia32_s_cet;
u64 guest_ssp;
u64 guest_ia32_int_ssp_table_addr;
u64 guest_ia32_lbr_ctl;
u64 padding64_5[2];
u64 xss_exit_bitmap;
u64 padding64_6[7];
u64 encls_exiting_bitmap;
u64 host_ia32_perf_global_ctrl;
u64 tsc_multiplier;
u64 host_ia32_s_cet;
u64 host_ssp;
u64 host_ia32_int_ssp_table_addr;
u64 padding64_6;
} __packed;
#define HV_VMX_ENLIGHTENED_CLEAN_FIELD_NONE 0