On 05/19/20 23:50, Lendacky, Thomas wrote: > BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=2198 > > Under SEV-ES, a WBINVD 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> > Signed-off-by: Tom Lendacky <thomas.lenda...@amd.com> > --- > .../Library/VmgExitLib/X64/VmgExitVcHandler.c | 36 +++++++++++++++++++ > 1 file changed, 36 insertions(+) > > diff --git a/OvmfPkg/Library/VmgExitLib/X64/VmgExitVcHandler.c > b/OvmfPkg/Library/VmgExitLib/X64/VmgExitVcHandler.c > index 50199845ceef..0cf26c052b32 100644 > --- a/OvmfPkg/Library/VmgExitLib/X64/VmgExitVcHandler.c > +++ b/OvmfPkg/Library/VmgExitLib/X64/VmgExitVcHandler.c > @@ -843,6 +843,38 @@ MmioExit ( > return Status; > } > > +/** > + Handle a WBINVD event. > + > + Use the VMGEXIT instruction to handle a WBINVD 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 > + @retval Others New exception value to propagate > + > +**/ > +STATIC > +UINT64 > +WbinvdExit ( > + IN OUT GHCB *Ghcb, > + IN OUT EFI_SYSTEM_CONTEXT_X64 *Regs, > + IN SEV_ES_INSTRUCTION_DATA *InstructionData > + ) > +{ > + UINT64 Status; > + > + Status = VmgExit (Ghcb, SVM_EXIT_WBINVD, 0, 0); > + if (Status) { > + return Status; > + } > + > + return 0;
(1) I'd simplify: return VmgExit (Ghcb, SVM_EXIT_WBINVD, 0, 0); unless you want to keep the Status variable (maybe for inserting DEBUG statements more easily, if needed). Even in that case: Status = VmgExit (Ghcb, SVM_EXIT_WBINVD, 0, 0); return Status; With either option adopted: Acked-by: Laszlo Ersek <ler...@redhat.com> (The real wart I'm trying to address here is the evaluation of "Status" in a logical context, as usual.) Thanks, Laszlo > +} > + > /** > Handle an MSR event. > > @@ -1238,6 +1270,10 @@ VmgExitHandleVc ( > NaeExit = MsrExit; > break; > > + case SVM_EXIT_WBINVD: > + NaeExit = WbinvdExit; > + break; > + > case SVM_EXIT_NPF: > NaeExit = MmioExit; > break; > -=-=-=-=-=-=-=-=-=-=-=- Groups.io Links: You receive all messages sent to this group. View/Reply Online (#60145): https://edk2.groups.io/g/devel/message/60145 Mute This Topic: https://groups.io/mt/74336572/21656 Group Owner: devel+ow...@edk2.groups.io Unsubscribe: https://edk2.groups.io/g/devel/unsub [arch...@mail-archive.com] -=-=-=-=-=-=-=-=-=-=-=-
