From 3ef8bfc2b3742df8d56a7651c897bc5929a77088 Mon Sep 17 00:00:00 2001 From: Tom Lendacky Date: Wed, 12 Aug 2020 15:21:39 -0500 Subject: OvmfPkg/VmgExitLib: Add support for MONITOR/MONITORX NAE events BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=2198 Under SEV-ES, a MONITOR/MONITORX intercept generates a #VC exception. VMGEXIT must be used to allow the hypervisor to handle this intercept. Cc: Jordan Justen Cc: Laszlo Ersek Cc: Ard Biesheuvel Acked-by: Laszlo Ersek Signed-off-by: Tom Lendacky Regression-tested-by: Laszlo Ersek --- OvmfPkg/Library/VmgExitLib/VmgExitVcHandler.c | 38 +++++++++++++++++++++++++++ 1 file changed, 38 insertions(+) (limited to 'OvmfPkg/Library') diff --git a/OvmfPkg/Library/VmgExitLib/VmgExitVcHandler.c b/OvmfPkg/Library/VmgExitLib/VmgExitVcHandler.c index 9bb32f0c3c..1e8b8ce424 100644 --- a/OvmfPkg/Library/VmgExitLib/VmgExitVcHandler.c +++ b/OvmfPkg/Library/VmgExitLib/VmgExitVcHandler.c @@ -858,6 +858,40 @@ MmioExit ( return Status; } +/** + Handle a MONITOR event. + + Use the VMGEXIT instruction to handle a MONITOR 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 +MonitorExit ( + IN OUT GHCB *Ghcb, + IN OUT EFI_SYSTEM_CONTEXT_X64 *Regs, + IN SEV_ES_INSTRUCTION_DATA *InstructionData + ) +{ + DecodeModRm (Regs, InstructionData); + + Ghcb->SaveArea.Rax = Regs->Rax; // Identity mapped, so VA = PA + GhcbSetRegValid (Ghcb, GhcbRax); + Ghcb->SaveArea.Rcx = Regs->Rcx; + GhcbSetRegValid (Ghcb, GhcbRcx); + Ghcb->SaveArea.Rdx = Regs->Rdx; + GhcbSetRegValid (Ghcb, GhcbRdx); + + return VmgExit (Ghcb, SVM_EXIT_MONITOR, 0, 0); +} + /** Handle a WBINVD event. @@ -1496,6 +1530,10 @@ VmgExitHandleVc ( NaeExit = WbinvdExit; break; + case SVM_EXIT_MONITOR: + NaeExit = MonitorExit; + break; + case SVM_EXIT_NPF: NaeExit = MmioExit; break; -- cgit v1.2.3