Re: [edk2-devel] [PATCH v1 03/13] UefiCpuPkg/SmmRelocationLib: Add library instance for OVMF

["Gerd Hoffmann" <kraxel@redhat.com>]

  Hi,

> > > 2) Existing SmBase configuration is different between the AMD & OVMF.
> > > OVMF:
> > >  AmdCpuState->x64.SMBASE = (UINT32)mSmBaseForAllCpus[CpuIndex];
> > >
> > > AMD:
> > >  if ((CpuSaveState->x86.SMMRevId & 0xFFFF) == 0) {
> > >     CpuSaveState->x86.SMBASE = (UINT32)mSmBaseForAllCpus[CpuIndex];
> > >   } else {
> > >     CpuSaveState->x64.SMBASE = (UINT32)mSmBaseForAllCpus[CpuIndex];
> > >   }

> I don't the background why AMD and OVMF has such difference. Maybe OVFM doesn't not support the MSR "EFER_ADDRESS".

It surely does, it's a rather essential MSR for x64 CPUs.

> > The SmBase configuration for OVMF looks suspicious to me.  I'm wondering
> > whenever the OVMF code actually works in Ia32 builds ...

Tested OvmfPkg/OvmfPkgIa32.dsc with SMM_REQUIRE == TRUE (master branch).
Doesn't boot.  The difference above (where the OVMF code does not
consider the 32bit case) could very well explain why 32bit support is
broken.  Switching to the AMD code might actually fix that.

Is the SmmRelocationLib approach supposed to work with mixed mode
firmware where PEI is running in ia32 mode and dxe/smm is running
in x64 mode (i.e. OvmfPkg/OvmfPkgIa32X64.dsc)?

take care,
  Gerd



-=-=-=-=-=-=-=-=-=-=-=-
Groups.io Links: You receive all messages sent to this group.
View/Reply Online (#117877): https://edk2.groups.io/g/devel/message/117877
Mute This Topic: https://groups.io/mt/105441992/7686176
Group Owner: devel+owner@edk2.groups.io
Unsubscribe: https://edk2.groups.io/g/devel/unsub [rebecca@openfw.io]
-=-=-=-=-=-=-=-=-=-=-=-