Re: [PATCH] x86/efi-bgrt: remove the check of the version field

From: Ingo Molnar
Date: Thu Aug 11 2016 - 04:52:06 EST



* Icenowy Zheng <icenowy@xxxxxxxx> wrote:

>
>
> 10.08.2016, 20:52, "Ingo Molnar" <mingo@xxxxxxxxxx>:
> > * Icenowy Zheng <icenowy@xxxxxxxx> wrote:
> >
> >>  Some broken firmwares have a wrongly filled version field in BGRT table.
> >>  (See http://wiki.osdev.org/Broken_UEFI_implementations )
> >>
> >>  As we know, these firmwares can also provide correct BGRT image, although
> >>  the table is wrong.
> >>
> >>  After removing the check of the version field, the kernel can now extract
> >>  the image correctly, and the information is also correct.
> >>
> >>  Tested on a Thinkpad E531 (68854UC).
> >
> > What's the practical effects of the bug - what problems does a missing
> > /sys/firmware/acpi/bgrt/ cause?
>
> Currently nothing uses this featues. However, one of my friend is trying to
> develop a splash screen which uses ACPI BGRT, like the splash screen
> of Windows 8 and above.
> Without the directory, there won't be any way to retrieve the vendor splash
> logo.

Ok - please add this information to the changelog.

Acked-by: Ingo Molnar <mingo@xxxxxxxxxx>

Thanks,

Ingo