Re: [RFC PATCH v5 092/104] KVM: TDX: Handle TDX PV HLT hypercall

From: Paolo Bonzini
Date: Thu Apr 07 2022 - 09:56:12 EST

On 3/4/22 20:49, isaku.yamahata@xxxxxxxxx wrote:
+ bool interrupt_disabled = tdvmcall_p1_read(vcpu);

Where is R12 documented for TDG.VP.VMCALL<Instruction.HLT>?

+ * Virtual interrupt can arrive after TDG.VM.VMCALL<HLT> during
+ * the TDX module executing. On the other hand, KVM doesn't
+ * know if vcpu was executing in the guest TD or the TDX module.

I don't understand this; why isn't it enough to check PI.ON or something like that as part of HLT emulation?

+ details.full = td_state_non_arch_read64(

TDX documentation says "the meaning of the field may change with Intel TDX module version", where is this field documented? I cannot find any "other guest state" fields in the TDX documentation.


+ if (details.vmxip)
+ return 1;
+ }
+ return kvm_emulate_halt_noskip(vcpu);