From: Tom Lendacky <thomas.lenda...@amd.com> BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=2198
Under SEV-ES, a VMMCALL intercept generates a #VC exception. VMGEXIT must be used to allow the hypervisor to handle this intercept. Cc: Jordan Justen <jordan.l.jus...@intel.com> Cc: Laszlo Ersek <ler...@redhat.com> Cc: Ard Biesheuvel <ard.biesheu...@arm.com> Acked-by: Laszlo Ersek <ler...@redhat.com> Signed-off-by: Tom Lendacky <thomas.lenda...@amd.com> --- OvmfPkg/Library/VmgExitLib/VmgExitVcHandler.c | 48 ++++++++++++++++++++ 1 file changed, 48 insertions(+) diff --git a/OvmfPkg/Library/VmgExitLib/VmgExitVcHandler.c b/OvmfPkg/Library/VmgExitLib/VmgExitVcHandler.c index ddaa19c7bcb4..dbea9c1f6aff 100644 --- a/OvmfPkg/Library/VmgExitLib/VmgExitVcHandler.c +++ b/OvmfPkg/Library/VmgExitLib/VmgExitVcHandler.c @@ -883,6 +883,50 @@ WbinvdExit ( return VmgExit (Ghcb, SVM_EXIT_WBINVD, 0, 0); } +/** + Handle a VMMCALL event. + + Use the VMGEXIT instruction to handle a VMMCALL event. + + @param[in, out] Ghcb Pointer to the Guest-Hypervisor Communication + Block + @param[in, out] Regs x64 processor context + @param[in] InstructionData Instruction parsing context + + @retval 0 Event handled successfully + @return New exception value to propagate + +**/ +STATIC +UINT64 +VmmCallExit ( + IN OUT GHCB *Ghcb, + IN OUT EFI_SYSTEM_CONTEXT_X64 *Regs, + IN SEV_ES_INSTRUCTION_DATA *InstructionData + ) +{ + UINT64 Status; + + DecodeModRm (Regs, InstructionData); + + Ghcb->SaveArea.Rax = Regs->Rax; + GhcbSetRegValid (Ghcb, GhcbRax); + Ghcb->SaveArea.Cpl = (UINT8) (Regs->Cs & 0x3); + GhcbSetRegValid (Ghcb, GhcbCpl); + + Status = VmgExit (Ghcb, SVM_EXIT_VMMCALL, 0, 0); + if (Status != 0) { + return Status; + } + + if (!GhcbIsRegValid (Ghcb, GhcbRax)) { + return UnsupportedExit (Ghcb, Regs, InstructionData); + } + Regs->Rax = Ghcb->SaveArea.Rax; + + return 0; +} + /** Handle an MSR event. @@ -1397,6 +1441,10 @@ VmgExitHandleVc ( NaeExit = MsrExit; break; + case SVM_EXIT_VMMCALL: + NaeExit = VmmCallExit; + break; + case SVM_EXIT_WBINVD: NaeExit = WbinvdExit; break; -- 2.28.0 -=-=-=-=-=-=-=-=-=-=-=- Groups.io Links: You receive all messages sent to this group. View/Reply Online (#64198): https://edk2.groups.io/g/devel/message/64198 Mute This Topic: https://groups.io/mt/76166997/21656 Group Owner: devel+ow...@edk2.groups.io Unsubscribe: https://edk2.groups.io/g/devel/unsub [arch...@mail-archive.com] -=-=-=-=-=-=-=-=-=-=-=-