Re: [edk2-devel] CcProbeLib not working for runtime calls

["Min Xu" <min.m.xu@intel.com>]

On August 18, 2022 12:58 PM, Gerd Hoffmann wrote:
> On Thu, Aug 18, 2022 at 01:47:37AM +0000, Xu, Min M wrote:
> > On August 17, 2022 7:05 PM, Gerd Hoffmann wrote:
> > > https://bugzilla.redhat.com/show_bug.cgi?id=2114858
> > >
> > > I think the call chain is:
> > >
> > > -> linux does efi runtime call
> > >   -> some debug message printed
> > >     -> OvmfPkg/Library/PlatformDebugLibIoPort/DebugLib.c
> > >       -> MdePkg/Library/BaseIoLibIntrinsic (IoWriteFifo8)
> > >         -> OvmfPkg/Library/CcProbeLib (CcProbe)
> > >           -> page fault when trying to access WorkArea
> > >
> >
> > I think this bug shares the same root cause.
> > https://bugzilla.tianocore.org/show_bug.cgi?id=3974
> 
> Yes, highly likely this is the same.
> 
> > And there is a fix awaiting for review.
> > https://edk2.groups.io/g/devel/message/91132
> 
> Hmm.  When the tdx/sev code actually works properly in runtime mode we
> should be able to reserve the workarea, mark it as runtime memory
> (SetMemorySpaceAttributes) and access it from runtime code, so we don't
> need two different ways to figure what CC mode we are running in.
Yes. I will submit a patch to fix it.

Thanks
Min