Sean Christopherson <seanjc@xxxxxxxxxx> writes: > On Tue, Aug 02, 2022, Vitaly Kuznetsov wrote: >> Updated Hyper-V Enlightened VMCS specification lists several new >> fields for the following features: >> >> - PerfGlobalCtrl >> - EnclsExitingBitmap >> - Tsc Scaling >> - GuestLbrCtl >> - CET >> - SSP >> >> Update the definition. The updated definition is available only when >> CPUID.0x4000000A.EBX BIT(0) is '1'. Add a define for it as well. >> >> Note: The latest TLFS is available at >> https://docs.microsoft.com/en-us/virtualization/hyper-v-on-windows/tlfs/tlfs >> >> Reviewed-by: Maxim Levitsky <mlevitsk@xxxxxxxxxx> >> Signed-off-by: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx> >> --- >> arch/x86/include/asm/hyperv-tlfs.h | 26 ++++++++++++++++++++++++-- >> 1 file changed, 24 insertions(+), 2 deletions(-) >> >> diff --git a/arch/x86/include/asm/hyperv-tlfs.h b/arch/x86/include/asm/hyperv-tlfs.h >> index 6f0acc45e67a..ebc27017fa48 100644 >> --- a/arch/x86/include/asm/hyperv-tlfs.h >> +++ b/arch/x86/include/asm/hyperv-tlfs.h >> @@ -138,6 +138,17 @@ >> #define HV_X64_NESTED_GUEST_MAPPING_FLUSH BIT(18) >> #define HV_X64_NESTED_MSR_BITMAP BIT(19) >> >> +/* >> + * Nested quirks. These are HYPERV_CPUID_NESTED_FEATURES.EBX bits. > > The "quirks" part is very confusing, largely because KVM has a well-established > quirks mechanism. I also don't see "quirks" anywhere in the TLFS documentation. > Can the "Nested quirks" part simply be dropped? > Yes, it's completely made up (just like I made up HV_X64_NESTED_EVMCS1_2022_UPDATE), let's drop it. >> + * >> + * Note: HV_X64_NESTED_EVMCS1_2022_UPDATE is not currently documented in any >> + * published TLFS version. When the bit is set, nested hypervisor can use >> + * 'updated' eVMCSv1 specification (perf_global_ctrl, s_cet, ssp, lbr_ctl, >> + * encls_exiting_bitmap, tsc_multiplier fields which were missing in 2016 >> + * specification). >> + */ >> +#define HV_X64_NESTED_EVMCS1_2022_UPDATE BIT(0) > > This bit is now defined[*], but the docs says it's only for perf_global_ctrl. Are > we expecting an update to the TLFS? > > Indicates support for the GuestPerfGlobalCtrl and HostPerfGlobalCtrl fields > in the enlightened VMCS. > > [*] https://docs.microsoft.com/en-us/virtualization/hyper-v-on-windows/tlfs/feature-discovery#hypervisor-nested-virtualization-features---0x4000000a > Oh well, better this than nothing. I'll ping the people who told me about this bit that their description is incomplete. >> + >> /* >> * 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 +570,20 @@ 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 >> -- >> 2.35.3 >> > -- Vitaly