Commit Message
Isaku Yamahata
Feb. 26, 2024, 8:26 a.m. UTC
From: Isaku Yamahata <isaku.yamahata@intel.com> Implement TDG.VP.VMCALL<GetTdVmCallInfo> hypercall. If the input value is zero, return success code and zero in output registers. TDG.VP.VMCALL<GetTdVmCallInfo> hypercall is a subleaf of TDG.VP.VMCALL to enumerate which TDG.VP.VMCALL sub leaves are supported. This hypercall is for future enhancement of the Guest-Host-Communication Interface (GHCI) specification. The GHCI version of 344426-001US defines it to require input R12 to be zero and to return zero in output registers, R11, R12, R13, and R14 so that guest TD enumerates no enhancement. Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com> --- v19: - rename TDG_VP_VMCALL_GET_TD_VM_CALL_INFO => TDVMCALL_GET_TD_VM_CALL_INFO --- arch/x86/include/asm/shared/tdx.h | 1 + arch/x86/kvm/vmx/tdx.c | 16 ++++++++++++++++ 2 files changed, 17 insertions(+)
diff --git a/arch/x86/include/asm/shared/tdx.h b/arch/x86/include/asm/shared/tdx.h index 28c4a62b7dba..3e8ce567fde0 100644 --- a/arch/x86/include/asm/shared/tdx.h +++ b/arch/x86/include/asm/shared/tdx.h @@ -22,6 +22,7 @@ #define TDCS_NOTIFY_ENABLES 0x9100000000000010 /* TDX hypercall Leaf IDs */ +#define TDVMCALL_GET_TD_VM_CALL_INFO 0x10000 #define TDVMCALL_MAP_GPA 0x10001 #define TDVMCALL_GET_QUOTE 0x10002 #define TDVMCALL_REPORT_FATAL_ERROR 0x10003 diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c index 3481c0b6ef2c..725cb40d0814 100644 --- a/arch/x86/kvm/vmx/tdx.c +++ b/arch/x86/kvm/vmx/tdx.c @@ -1353,6 +1353,20 @@ static int tdx_emulate_wrmsr(struct kvm_vcpu *vcpu) return 1; } +static int tdx_get_td_vm_call_info(struct kvm_vcpu *vcpu) +{ + if (tdvmcall_a0_read(vcpu)) + tdvmcall_set_return_code(vcpu, TDVMCALL_INVALID_OPERAND); + else { + tdvmcall_set_return_code(vcpu, TDVMCALL_SUCCESS); + kvm_r11_write(vcpu, 0); + tdvmcall_a0_write(vcpu, 0); + tdvmcall_a1_write(vcpu, 0); + tdvmcall_a2_write(vcpu, 0); + } + return 1; +} + static int handle_tdvmcall(struct kvm_vcpu *vcpu) { if (tdvmcall_exit_type(vcpu)) @@ -1371,6 +1385,8 @@ static int handle_tdvmcall(struct kvm_vcpu *vcpu) return tdx_emulate_rdmsr(vcpu); case EXIT_REASON_MSR_WRITE: return tdx_emulate_wrmsr(vcpu); + case TDVMCALL_GET_TD_VM_CALL_INFO: + return tdx_get_td_vm_call_info(vcpu); default: break; }