Re: [edk2-devel] [PATCH 1/1] OvmfPkg/PlatformInitLib: pass through reservations from qemu

["Ard Biesheuvel" <ardb@kernel.org>]

On Mon, 16 Jan 2023 at 21:10, Tom Lendacky <thomas.lendacky@amd.com> wrote:
>
> On 1/16/23 11:09, Ard Biesheuvel wrote:
> > On Thu, 12 Jan 2023 at 18:09, Tom Lendacky <thomas.lendacky@amd.com> wrote:
> >>
> >> On 12/6/22 23:32, Gerd Hoffmann via groups.io wrote:
> >>> qemu uses the etc/e820 fw_cfg file not only for memory, but
> >>> also for reservations.  Handle reservations by adding resource
> >>> descriptor hobs for them.
> >>>
> >>> A typical qemu configuration has a small reservation between
> >>> lapic and flash:
> >>>
> >>>     # sudo cat /proc/iomem
> >>>     [ ... ]
> >>>     fee00000-fee00fff : Local APIC
> >>>     feffc000-feffffff : Reserved          <= HERE
> >>>     ffc00000-ffffffff : Reserved
> >>>     [ ... ]
> >>>
> >>> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
> >>
> >> On newer versions of Qemu, this patch causes a boot failure on my
> >> AMD system with the following output:
> >>
> >> ...
> >> PciHostBridgeUtilityInitRootBridge: populated root bus 0, with room for 255 subordinate bus(es)
> >> RootBridge: PciRoot(0x0)
> >>     Support/Attr: 70069 / 70069
> >>       DmaAbove4G: No
> >> NoExtConfSpace: No
> >>        AllocAttr: 3 (CombineMemPMem Mem64Decode)
> >>              Bus: 0 - FF Translation=0
> >>               Io: 6000 - FFFF Translation=0
> >>              Mem: C0000000 - FBFFFFFF Translation=0
> >>       MemAbove4G: E000000000 - FFFFFFFFFF Translation=0
> >>             PMem: FFFFFFFFFFFFFFFF - 0 Translation=0
> >>      PMemAbove4G: FFFFFFFFFFFFFFFF - 0 Translation=0
> >> PciHostBridgeDxe: IntersectMemoryDescriptor: desc [FD00000000, 10000000000) type 1 cap 8000000000026000 conflicts with aperture [E000000000, 10000000000) cap 1
> >>
> >> ASSERT_EFI_ERROR (Status = Invalid Parameter)
> >> ASSERT [PciHostBridgeDxe] /root/kernels/ovmf-build-X64/MdeModulePkg/Bus/Pci/PciHostBridgeDxe/PciHostBridge.c(550): !(((INTN)(RETURN_STATUS)(Status)) < 0)
> >>
> >> Doing some bisecting, before Qemu patch
> >>
> >>      8504f129450b ("i386/pc: relocate 4g start to 1T where applicable")
> >>
> >> this issue wasn't observed. And before this OVMF patch, the newer version
> >> of Qemu doesn't have an issue.
> >>
> >> Also, if I add host-phys-bits=true to the Qemu -cpu parameter, then
> >> the issue isn't observed regardless of Qemu/OVMF level.
> >>
> >> I'm hoping someone has an understanding of what is going on and what
> >> can be done to fix it.
> >>
> >
> > Could someone look into this please? Gerd?
>
> Looks like Gerd is already on it.
>
> See https://bugzilla.tianocore.org/show_bug.cgi?id=4251
>

Right, I didn't realize these things were related.

In any case, those patches have been merged now - care to check
whether the issue has been resolved? Thanks.