From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mga01.intel.com (mga01.intel.com [192.55.52.88]) by mx.groups.io with SMTP id smtpd.web12.43668.1635772972691691836 for ; Mon, 01 Nov 2021 06:22:52 -0700 Authentication-Results: mx.groups.io; dkim=missing; spf=pass (domain: intel.com, ip: 192.55.52.88, mailfrom: min.m.xu@intel.com) X-IronPort-AV: E=McAfee;i="6200,9189,10154"; a="254617502" X-IronPort-AV: E=Sophos;i="5.87,199,1631602800"; d="scan'208";a="254617502" Received: from orsmga008.jf.intel.com ([10.7.209.65]) by fmsmga101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 01 Nov 2021 06:16:47 -0700 X-IronPort-AV: E=Sophos;i="5.87,199,1631602800"; d="scan'208";a="500035458" Received: from mxu9-mobl1.ccr.corp.intel.com ([10.255.29.216]) by orsmga008-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 01 Nov 2021 06:16:45 -0700 From: "Min Xu" To: devel@edk2.groups.io Cc: Min Xu , Ard Biesheuvel , Jiewen Yao , Jordan Justen , Brijesh Singh , Erdem Aktas , James Bottomley , Tom Lendacky , Gerd Hoffmann Subject: [PATCH V3 04/29] OvmfPkg: Extend VmgExitLib to handle #VE exception Date: Mon, 1 Nov 2021 21:15:53 +0800 Message-Id: X-Mailer: git-send-email 2.29.2.windows.2 In-Reply-To: References: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit RFC： https://bugzilla.tianocore.org/show_bug.cgi?id=3429 The base VmgExitLib library provides a default limited interface to handle #VE exception. To provide full support, the OVMF version of VmgExitLib is extended to provide full support of #VE handler. PcdIgnoreVeHalt is created in OvmfPkg.dec to ignore the VE halt. Cc: Ard Biesheuvel Cc: Jiewen Yao Cc: Jordan Justen Cc: Brijesh Singh Cc: Erdem Aktas Cc: James Bottomley Cc: Jiewen Yao Cc: Tom Lendacky Cc: Gerd Hoffmann Signed-off-by: Min Xu --- OvmfPkg/Library/VmgExitLib/SecVmgExitLib.inf | 3 +- .../Library/VmgExitLib/VmTdExitVeHandler.c | 515 ++++++++++++++++++ OvmfPkg/Library/VmgExitLib/VmgExitLib.inf | 4 + OvmfPkg/OvmfPkg.dec | 3 + 4 files changed, 524 insertions(+), 1 deletion(-) create mode 100644 OvmfPkg/Library/VmgExitLib/VmTdExitVeHandler.c diff --git a/OvmfPkg/Library/VmgExitLib/SecVmgExitLib.inf b/OvmfPkg/Library/VmgExitLib/SecVmgExitLib.inf index e6f6ea7972fd..20d381387bf9 100644 --- a/OvmfPkg/Library/VmgExitLib/SecVmgExitLib.inf +++ b/OvmfPkg/Library/VmgExitLib/SecVmgExitLib.inf @@ -25,6 +25,7 @@ VmgExitVcHandler.c VmgExitVcHandler.h SecVmgExitVcHandler.c + VmTdExitVeHandler.c [Packages] MdePkg/MdePkg.dec @@ -42,4 +43,4 @@ [FixedPcd] gUefiOvmfPkgTokenSpaceGuid.PcdOvmfSecGhcbBackupBase gUefiOvmfPkgTokenSpaceGuid.PcdOvmfSecGhcbBackupSize - + gUefiOvmfPkgTokenSpaceGuid.PcdIgnoreVeHalt diff --git a/OvmfPkg/Library/VmgExitLib/VmTdExitVeHandler.c b/OvmfPkg/Library/VmgExitLib/VmTdExitVeHandler.c new file mode 100644 index 000000000000..fe157208154a --- /dev/null +++ b/OvmfPkg/Library/VmgExitLib/VmTdExitVeHandler.c @@ -0,0 +1,515 @@ +/** @file + + Copyright (c) 2021, Intel Corporation. All rights reserved.
+ + SPDX-License-Identifier: BSD-2-Clause-Patent + +**/ + +#include +#include +#include +#include +#include +#include +#include + +typedef union { + struct { + UINT32 Eax; + UINT32 Edx; + } Regs; + UINT64 Val; +} MSR_DATA; + +typedef union { + UINT8 Val; + struct { + UINT8 B:1; + UINT8 X:1; + UINT8 R:1; + UINT8 W:1; + } Bits; +} REX; + +typedef union { + UINT8 Val; + struct { + UINT8 Rm:3; + UINT8 Reg:3; + UINT8 Mod:2; + } Bits; +} MODRM; + +typedef struct { + UINT64 Regs[4]; +} CPUID_DATA; + +/** + Handle an CPUID event. + + Use the TDVMCALL instruction to handle cpuid #ve + + @param[in, out] Regs x64 processor context + @param[in] Veinfo VE Info + + @retval 0 Event handled successfully + @return New exception value to propagate +**/ +STATIC +UINT64 +EFIAPI +CpuIdExit ( + IN EFI_SYSTEM_CONTEXT_X64 *Regs, + IN TDCALL_VEINFO_RETURN_DATA *Veinfo + ) +{ + CPUID_DATA CpuIdData; + UINT64 Status; + + Status = TdVmCallCpuid (Regs->Rax, Regs->Rcx, &CpuIdData); + + if (Status == 0) { + Regs->Rax = CpuIdData.Regs[0]; + Regs->Rbx = CpuIdData.Regs[1]; + Regs->Rcx = CpuIdData.Regs[2]; + Regs->Rdx = CpuIdData.Regs[3]; + } + + return Status; +} + +/** + Handle an IO event. + + Use the TDVMCALL instruction to handle either an IO read or an IO write. + + @param[in, out] Regs x64 processor context + @param[in] Veinfo VE Info + + @retval 0 Event handled successfully + @return New exception value to propagate +**/ +STATIC +UINT64 +EFIAPI +IoExit ( + IN OUT EFI_SYSTEM_CONTEXT_X64 *Regs, + IN TDCALL_VEINFO_RETURN_DATA *Veinfo + ) +{ + BOOLEAN Write; + UINTN Size; + UINTN Port; + UINT64 Val; + UINT64 RepCnt; + UINT64 Status; + + Val = 0; + Write = Veinfo->ExitQualification.Io.Direction ? FALSE : TRUE; + Size = Veinfo->ExitQualification.Io.Size + 1; + Port = Veinfo->ExitQualification.Io.Port; + + if (Veinfo->ExitQualification.Io.String) { + // + // If REP is set, get rep-cnt from Rcx + // + RepCnt = Veinfo->ExitQualification.Io.Rep ? Regs->Rcx : 1; + + while (RepCnt) { + Val = 0; + if (Write == TRUE) { + CopyMem (&Val, (VOID *) Regs->Rsi, Size); + Regs->Rsi += Size; + } + + Status = TdVmCall (EXIT_REASON_IO_INSTRUCTION, Size, Write, Port, Val, (Write ? NULL : &Val)); + if (Status != 0) { + break; + } + if (Write == FALSE) { + CopyMem ((VOID *) Regs->Rdi, &Val, Size); + Regs->Rdi += Size; + } + + if (Veinfo->ExitQualification.Io.Rep) { + Regs->Rcx -= 1; + } + RepCnt -= 1; + } + } else { + if (Write == TRUE) { + CopyMem (&Val, (VOID *) &Regs->Rax, Size); + } + Status = TdVmCall (EXIT_REASON_IO_INSTRUCTION, Size, Write, Port, Val, (Write ? NULL : &Val)); + if ((Status == 0) && (Write == FALSE)) { + CopyMem ((VOID *) &Regs->Rax, &Val, Size); + } + } + return Status; +} + +/** + Handle an READ MSR event. + + Use the TDVMCALL instruction to handle msr read + + @param[in, out] Regs x64 processor context + @param[in] Veinfo VE Info + + @retval 0 Event handled successfully + @return New exception value to propagate +**/ +STATIC +UINT64 +ReadMsrExit ( + IN OUT EFI_SYSTEM_CONTEXT_X64 *Regs, + IN TDCALL_VEINFO_RETURN_DATA *Veinfo + ) +{ + MSR_DATA Data; + UINT64 Status; + + Status = TdVmCall (EXIT_REASON_MSR_READ, Regs->Rcx, 0, 0, 0, &Data); + if (Status == 0) { + Regs->Rax = Data.Regs.Eax; + Regs->Rdx = Data.Regs.Edx; + } + + return Status; +} + +/** + Handle an WRITE MSR event. + + Use the TDVMCALL instruction to handle msr write + + @param[in, out] Regs x64 processor context + @param[in] Veinfo VE Info + + @retval 0 Event handled successfully + @return New exception value to propagate +**/ +STATIC +UINT64 +WriteMsrExit ( + IN OUT EFI_SYSTEM_CONTEXT_X64 *Regs, + IN TDCALL_VEINFO_RETURN_DATA *Veinfo + ) +{ + UINT64 Status; + MSR_DATA Data; + + Data.Regs.Eax = (UINT32) Regs->Rax; + Data.Regs.Edx = (UINT32) Regs->Rdx; + + Status = TdVmCall (EXIT_REASON_MSR_WRITE, Regs->Rcx, Data.Val, 0, 0, NULL); + + return Status; +} + +STATIC +VOID +EFIAPI +TdxDecodeInstruction ( + IN UINT8 *Rip +) +{ + UINTN i; + DEBUG ((DEBUG_INFO,"TDX: #TD[EPT] instruction (%p):", Rip)); + for (i = 0; i < 15; i++) { + DEBUG ((DEBUG_INFO, "%02x:", Rip[i])); + } + DEBUG ((DEBUG_INFO, "\n")); +} + +#define TDX_DECODER_BUG_ON(x) \ + if ((x)) { \ + TdxDecodeInstruction(Rip); \ + TdVmCall(TDVMCALL_HALT, 0, 0, 0, 0, 0); \ + } + +STATIC +UINT64 * +EFIAPI +GetRegFromContext ( + IN EFI_SYSTEM_CONTEXT_X64 *Regs, + IN UINTN RegIndex +) +{ + switch (RegIndex) { + case 0: return &Regs->Rax; break; + case 1: return &Regs->Rcx; break; + case 2: return &Regs->Rdx; break; + case 3: return &Regs->Rbx; break; + case 4: return &Regs->Rsp; break; + case 5: return &Regs->Rbp; break; + case 6: return &Regs->Rsi; break; + case 7: return &Regs->Rdi; break; + case 8: return &Regs->R8; break; + case 9: return &Regs->R9; break; + case 10: return &Regs->R10; break; + case 11: return &Regs->R11; break; + case 12: return &Regs->R12; break; + case 13: return &Regs->R13; break; + case 14: return &Regs->R14; break; + case 15: return &Regs->R15; break; + } + return NULL; +} + +/** + Handle an MMIO event. + + Use the TDVMCALL instruction to handle either an mmio read or an mmio write. + + @param[in, out] Regs x64 processor context + @param[in] Veinfo VE Info + + @retval 0 Event handled successfully + @return New exception value to propagate +**/ +STATIC +INTN +EFIAPI +MmioExit ( + IN OUT EFI_SYSTEM_CONTEXT_X64 *Regs, + IN TDCALL_VEINFO_RETURN_DATA *Veinfo + ) +{ + UINT64 Status; + UINT32 MmioSize; + UINT32 RegSize;; + UINT8 OpCode; + BOOLEAN SeenRex; + UINT64 *Reg; + UINT8 *Rip; + UINT64 Val; + UINT32 OpSize; + MODRM ModRm; + REX Rex; + + Rip = (UINT8 *) Regs->Rip; + Val = 0; + Rex.Val = 0; + SeenRex = FALSE; + + // + // Default to 32bit transfer + // + OpSize = 4; + + do { + OpCode = *Rip++; + if (OpCode == 0x66) { + OpSize = 2; + } else if (OpCode == 0x64 || OpCode == 0x65 || OpCode == 0x67) { + continue; + } else if (OpCode >= 0x40 && OpCode <= 0x4f) { + SeenRex = TRUE; + Rex.Val = OpCode; + } else { + break; + } + } while (TRUE); + + // + // We need to have at least 2 more bytes for this instruction + // + TDX_DECODER_BUG_ON(((UINT64)Rip - Regs->Rip) > 13); + + OpCode = *Rip++; + // + // Two-byte opecode, get next byte + // + if (OpCode == 0x0F) { + OpCode = *Rip++; + } + + switch (OpCode) { + case 0x88: + case 0x8A: + case 0xB6: + MmioSize = 1; + break; + case 0xB7: + MmioSize = 2; + break; + default: + MmioSize = Rex.Bits.W ? 8 : OpSize; + break; + } + + /* Punt on AH/BH/CH/DH unless it shows up. */ + ModRm.Val = *Rip++; + TDX_DECODER_BUG_ON(MmioSize == 1 && ModRm.Bits.Reg > 4 && !SeenRex && OpCode != 0xB6); + Reg = GetRegFromContext (Regs, ModRm.Bits.Reg | ((int)Rex.Bits.R << 3)); + TDX_DECODER_BUG_ON(!Reg); + + if (ModRm.Bits.Rm == 4) + ++Rip; /* SIB byte */ + + if (ModRm.Bits.Mod == 2 || (ModRm.Bits.Mod == 0 && ModRm.Bits.Rm == 5)) + Rip += 4; /* DISP32 */ + else if (ModRm.Bits.Mod == 1) + ++Rip; /* DISP8 */ + + switch (OpCode) { + case 0x88: + case 0x89: + CopyMem ((void *)&Val, Reg, MmioSize); + Status = TdVmCall (TDVMCALL_MMIO, MmioSize, 1, Veinfo->GuestPA, Val, 0); + break; + case 0xC7: + CopyMem ((void *)&Val, Rip, OpSize); + Status = TdVmCall (TDVMCALL_MMIO, MmioSize, 1, Veinfo->GuestPA, Val, 0); + Rip += OpSize; + default: + // + // 32-bit write registers are zero extended to the full register + // Hence 'MOVZX r[32/64], r/m16' is + // hardcoded to reg size 8, and the straight MOV case has a reg + // size of 8 in the 32-bit read case. + // + switch (OpCode) { + case 0xB6: + RegSize = Rex.Bits.W ? 8 : OpSize; + break; + case 0xB7: + RegSize = 8; + break; + default: + RegSize = MmioSize == 4 ? 8 : MmioSize; + break; + } + + Status = TdVmCall (TDVMCALL_MMIO, MmioSize, 0, Veinfo->GuestPA, 0, &Val); + if (Status == 0) { + ZeroMem (Reg, RegSize); + CopyMem (Reg, (void *)&Val, MmioSize); + } + } + + if (Status == 0) { + TDX_DECODER_BUG_ON(((UINT64)Rip - Regs->Rip) > 15); + + // + // We change instruction length to reflect true size so handler can + // bump rip + // + Veinfo->ExitInstructionLength = (UINT32)((UINT64)Rip - Regs->Rip); + } + + return Status; +} + +/** + Handle a #VE exception. + + Performs the necessary processing to handle a #VE exception. + + @param[in, out] ExceptionType Pointer to an EFI_EXCEPTION_TYPE to be set + as value to use on error. + @param[in, out] SystemContext Pointer to EFI_SYSTEM_CONTEXT + + @retval EFI_SUCCESS Exception handled + @retval EFI_UNSUPPORTED #VE not supported, (new) exception value to + propagate provided + @retval EFI_PROTOCOL_ERROR #VE handling failed, (new) exception value to + propagate provided + +**/ +EFI_STATUS +EFIAPI +VmTdExitHandleVe ( + IN OUT EFI_EXCEPTION_TYPE *ExceptionType, + IN OUT EFI_SYSTEM_CONTEXT SystemContext + ) +{ + UINT64 Status; + TD_RETURN_DATA ReturnData; + EFI_SYSTEM_CONTEXT_X64 *Regs; + + Regs = SystemContext.SystemContextX64; + Status = TdCall (TDCALL_TDGETVEINFO, 0, 0, 0, &ReturnData); + ASSERT (Status == 0); + if (Status != 0) { + DEBUG ((DEBUG_ERROR, "#VE happened. TDGETVEINFO failed with Status = 0x%llx\n", Status)); + TdVmCall (TDVMCALL_HALT, 0, 0, 0, 0, 0); + } + + switch (ReturnData.VeInfo.ExitReason) { + case EXIT_REASON_CPUID: + Status = CpuIdExit (Regs, &ReturnData.VeInfo); + DEBUG ((DEBUG_VERBOSE , + "CPUID #VE happened, ExitReasion is %d, ExitQualification = 0x%x.\n", + ReturnData.VeInfo.ExitReason, ReturnData.VeInfo.ExitQualification.Val + )); + break; + + case EXIT_REASON_HLT: + if (FixedPcdGetBool (PcdIgnoreVeHalt) == FALSE) { + Status = TdVmCall (EXIT_REASON_HLT, 0, 0, 0, 0, 0); + } + break; + + case EXIT_REASON_IO_INSTRUCTION: + Status = IoExit (Regs, &ReturnData.VeInfo); + DEBUG ((DEBUG_VERBOSE , + "IO_Instruction #VE happened, ExitReasion is %d, ExitQualification = 0x%x.\n", + ReturnData.VeInfo.ExitReason, ReturnData.VeInfo.ExitQualification.Val + )); + break; + + case EXIT_REASON_MSR_READ: + Status = ReadMsrExit (Regs, &ReturnData.VeInfo); + DEBUG ((DEBUG_VERBOSE , + "RDMSR #VE happened, ExitReasion is %d, ExitQualification = 0x%x. Regs->Rcx=0x%llx, Status = 0x%llx\n", + ReturnData.VeInfo.ExitReason, ReturnData.VeInfo.ExitQualification.Val, Regs->Rcx, Status + )); + break; + + case EXIT_REASON_MSR_WRITE: + Status = WriteMsrExit (Regs, &ReturnData.VeInfo); + DEBUG ((DEBUG_VERBOSE , + "WRMSR #VE happened, ExitReasion is %d, ExitQualification = 0x%x. Regs->Rcx=0x%llx, Status = 0x%llx\n", + ReturnData.VeInfo.ExitReason, ReturnData.VeInfo.ExitQualification.Val, Regs->Rcx, Status + )); + break; + + case EXIT_REASON_EPT_VIOLATION: + Status = MmioExit (Regs, &ReturnData.VeInfo); + DEBUG ((DEBUG_VERBOSE , + "MMIO #VE happened, ExitReasion is %d, ExitQualification = 0x%x.\n", + ReturnData.VeInfo.ExitReason, ReturnData.VeInfo.ExitQualification.Val + )); + break; + + case EXIT_REASON_VMCALL: + case EXIT_REASON_MWAIT_INSTRUCTION: + case EXIT_REASON_MONITOR_INSTRUCTION: + case EXIT_REASON_WBINVD: + case EXIT_REASON_RDPMC: + /* Handle as nops. */ + break; + + default: + DEBUG ((DEBUG_ERROR, + "Unsupported #VE happened, ExitReason is %d, ExitQualification = 0x%x.\n", + ReturnData.VeInfo.ExitReason, ReturnData.VeInfo.ExitQualification.Val + )); + + ASSERT (FALSE); + CpuDeadLoop (); + } + if (Status) { + DEBUG ((DEBUG_ERROR, + "#VE Error (0x%llx) returned from host, ExitReason is %d, ExitQualification = 0x%x.\n", + Status, ReturnData.VeInfo.ExitReason, ReturnData.VeInfo.ExitQualification.Val + )); + + TdVmCall (TDVMCALL_HALT, 0, 0, 0, 0, 0); + } + SystemContext.SystemContextX64->Rip += ReturnData.VeInfo.ExitInstructionLength; + return EFI_SUCCESS; +} diff --git a/OvmfPkg/Library/VmgExitLib/VmgExitLib.inf b/OvmfPkg/Library/VmgExitLib/VmgExitLib.inf index c66c68726cdb..e3da12af2f7a 100644 --- a/OvmfPkg/Library/VmgExitLib/VmgExitLib.inf +++ b/OvmfPkg/Library/VmgExitLib/VmgExitLib.inf @@ -25,6 +25,7 @@ VmgExitVcHandler.c VmgExitVcHandler.h PeiDxeVmgExitVcHandler.c + VmTdExitVeHandler.c [Packages] MdePkg/MdePkg.dec @@ -37,4 +38,7 @@ DebugLib LocalApicLib MemEncryptSevLib + TdxLib +[Pcd] + gUefiOvmfPkgTokenSpaceGuid.PcdIgnoreVeHalt diff --git a/OvmfPkg/OvmfPkg.dec b/OvmfPkg/OvmfPkg.dec index 340d83f794d0..2124bd639399 100644 --- a/OvmfPkg/OvmfPkg.dec +++ b/OvmfPkg/OvmfPkg.dec @@ -350,6 +350,9 @@ gUefiOvmfPkgTokenSpaceGuid.PcdBfvRawDataOffset|0|UINT32|0x56 gUefiOvmfPkgTokenSpaceGuid.PcdBfvRawDataSize|0|UINT32|0x57 + ## Ignore the VE halt in Tdx + gUefiOvmfPkgTokenSpaceGuid.PcdIgnoreVeHalt|FALSE|BOOLEAN|0x58 + [PcdsDynamic, PcdsDynamicEx] gUefiOvmfPkgTokenSpaceGuid.PcdEmuVariableEvent|0|UINT64|2 gUefiOvmfPkgTokenSpaceGuid.PcdOvmfFlashVariablesEnable|FALSE|BOOLEAN|0x10 -- 2.29.2.windows.2