Re: [PATCH] efi/libstub/arm64: Enable __efistub_global define in .data section

[Victor Erminpour]

On 4/10/20 1:09 AM, Ard Biesheuvel wrote:
> On Thu, 9 Apr 2020 at 23:44, Victor Erminpour
> <victor.erminpour@xxxxxxxxxx> wrote:
> > Enable the __efistub_global define to place variables in the
> > .data section for both CONFIG_ARM and CONFIG_ARM64.
> >
> > This places the EFIstub sys_table variable and other EFIstub
> > static variables in the .data section for both CONFIG_ARM and
> > CONFIG_ARM64.
>
> What does that achieve?

Hi Ard,

Without placing these global variables in .data, I get the
following errors when booting an ARM64 EFI system:

EFI stub: ERROR: Exit boot services failed.
EFI stub: ERROR: Failed to update FDT and exit boot services


I know that the ARM64 linker script is supposed to put the
.init.bss into the .init.data section, but I don't think this
is happening for all systems.

Having it explicitly enabled for CONFIG_ARM64 worked for me.


Regards,
--Victor


> > Signed-off-by: Victor Erminpour <victor.erminpour@xxxxxxxxxx>
> > ---
> >   drivers/firmware/efi/libstub/efistub.h | 2 +-
> >   1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/firmware/efi/libstub/efistub.h b/drivers/firmware/efi/libstub/efistub.h
> > index c244b16..59932d6 100644
> > --- a/drivers/firmware/efi/libstub/efistub.h
> > +++ b/drivers/firmware/efi/libstub/efistub.h
> > @@ -25,7 +25,7 @@
> >   #define EFI_ALLOC_ALIGN                EFI_PAGE_SIZE
> >   #endif
> >
> > -#ifdef CONFIG_ARM
> > +#if defined(CONFIG_ARM) || defined(CONFIG_ARM64)
> >   #define __efistub_global       __section(.data)
> >   #else
> >   #define __efistub_global

--
Victor Hugo Erminpour
Principal Member of Technical Staff
Oracle America