[PATCH 03/25] KVM: TDX: Add TDX "architectural" error codes

Rick Edgecombe
2024-08-12T22:48:30Z

From: Sean Christopherson <sean.j.christopherson@intel.com>

Add error codes for the TDX SEAMCALLs both for TDX VMM side for TDH
SEAMCALL and TDX guest side for TDG.VP.VMCALL. KVM issues the TDX
SEAMCALLs and checks its error code. KVM handles hypercall from the TDX
guest and may return an error. So error code for the TDX guest is also
needed.

TDX SEAMCALL uses bits 31:0 to return more information, so these error
codes will only exactly match RAX[63:32]. Error codes for TDG.VP.VMCALL is
defined by TDX Guest-Host-Communication interface spec.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Yuan Yao <yuan.yao@intel.com>
Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com>
---
v19:
- Drop TDX_EPT_WALK_FAILED, TDX_EPT_ENTRY_NOT_FREE
- Rename TDG_VP_VMCALL_ => TDVMCALL_ to match the existing code
- Move TDVMCALL error codes to shared/tdx.h
- Added TDX_OPERAND_ID_TDR
- Fix bisectability issues in headers (Kai)
---
arch/x86/include/asm/shared/tdx.h | 6 ++++++
arch/x86/kvm/vmx/tdx.h | 1 +
arch/x86/kvm/vmx/tdx_errno.h | 36 +++++++++++++++++++++++++++++++
3 files changed, 43 insertions(+)
create mode 100644 arch/x86/kvm/vmx/tdx_errno.h

diff --git a/arch/x86/include/asm/shared/tdx.h b/arch/x86/include/asm/shared/tdx.h
index fdfd41511b02..6ebbf8ee80b3 100644
--- a/arch/x86/include/asm/shared/tdx.h
+++ b/arch/x86/include/asm/shared/tdx.h
@@ -28,6 +28,12 @@

#define TDVMCALL_STATUS_RETRY 1

+/*
+ * TDG.VP.VMCALL Status Codes (returned in R10)
+ */
+#define TDVMCALL_SUCCESS 0x0000000000000000ULL
+#define TDVMCALL_INVALID_OPERAND 0x8000000000000000ULL
+
/*
* Bitmasks of exposed registers (with VMM).
*/
diff --git a/arch/x86/kvm/vmx/tdx.h b/arch/x86/kvm/vmx/tdx.h
index 1d6fa81a072d..faed454385ca 100644
--- a/arch/x86/kvm/vmx/tdx.h
+++ b/arch/x86/kvm/vmx/tdx.h
@@ -2,6 +2,7 @@
#define __KVM_X86_VMX_TDX_H

#include "tdx_arch.h"
+#include "tdx_errno.h"

#ifdef CONFIG_INTEL_TDX_HOST
void tdx_bringup(void);
diff --git a/arch/x86/kvm/vmx/tdx_errno.h b/arch/x86/kvm/vmx/tdx_errno.h
new file mode 100644
index 000000000000..dc3fa2a58c2c
--- /dev/null
+++ b/arch/x86/kvm/vmx/tdx_errno.h
@@ -0,0 +1,36 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* architectural status code for SEAMCALL */
+
+#ifndef __KVM_X86_TDX_ERRNO_H
+#define __KVM_X86_TDX_ERRNO_H
+
+#define TDX_SEAMCALL_STATUS_MASK 0xFFFFFFFF00000000ULL
+
+/*
+ * TDX SEAMCALL Status Codes (returned in RAX)
+ */
+#define TDX_NON_RECOVERABLE_VCPU 0x4000000100000000ULL
+#define TDX_INTERRUPTED_RESUMABLE 0x8000000300000000ULL
+#define TDX_OPERAND_INVALID 0xC000010000000000ULL
+#define TDX_OPERAND_BUSY 0x8000020000000000ULL
+#define TDX_PREVIOUS_TLB_EPOCH_BUSY 0x8000020100000000ULL
+#define TDX_PAGE_METADATA_INCORRECT 0xC000030000000000ULL
+#define TDX_VCPU_NOT_ASSOCIATED 0x8000070200000000ULL
+#define TDX_KEY_GENERATION_FAILED 0x8000080000000000ULL
+#define TDX_KEY_STATE_INCORRECT 0xC000081100000000ULL
+#define TDX_KEY_CONFIGURED 0x0000081500000000ULL
+#define TDX_NO_HKID_READY_TO_WBCACHE 0x0000082100000000ULL
+#define TDX_FLUSHVP_NOT_DONE 0x8000082400000000ULL
+#define TDX_EPT_WALK_FAILED 0xC0000B0000000000ULL
+#define TDX_EPT_ENTRY_STATE_INCORRECT 0xC0000B0D00000000ULL
+
+/*
+ * TDX module operand ID, appears in 31:0 part of error code as
+ * detail information
+ */
+#define TDX_OPERAND_ID_RCX 0x01
+#define TDX_OPERAND_ID_TDR 0x80
+#define TDX_OPERAND_ID_SEPT 0x92
+#define TDX_OPERAND_ID_TD_EPOCH 0xa9
+
+#endif /* __KVM_X86_TDX_ERRNO_H */
--
2.34.1