On 13/03/2023 12:21 pm, Roger Pau Monné wrote: > On Mon, Mar 13, 2023 at 11:55:56AM +0000, Andrew Cooper wrote: >> On 12/03/2023 7:54 am, Huang Rui wrote: >>> From: Roger Pau Monne <roger....@citrix.com> >>> >>> The VFCT ACPI table is used by AMD GPUs to expose the vbios ROM image >>> from the firmware instead of doing it on the PCI ROM on the physical >>> device. >>> >>> As such, this needs to be available for PVH dom0 to access, or else >>> the GPU won't work. >>> >>> Reported-by: Huang Rui <ray.hu...@amd.com> >>> Signed-off-by: Roger Pau Monné <roger....@citrix.com> >>> Acked-and-Tested-by: Huang Rui <ray.hu...@amd.com> >>> Release-acked-by: Henry Wang <henry.w...@arm.com> >>> Signed-off-by: Huang Rui <ray.hu...@amd.com> >> Huh... Despite the release ack, this didn't get committed for 4.17. > There was a pending query from Jan as to where was this table > signature documented or at least registered, as it's not in the ACPI > spec or any related files. > > I don't oppose to the change, as it's already used by Linux, so I > think it's impossible for the table signature to be reused, even if > not properly documented (it would cause havoc). > > It's however not ideal to set this kind of precedents.
It's not great, but this exists in real systems, for several generations it seems. Making things work for users trumps any idealistic beliefs about firmware actually conforming to spec. ~Andrew
