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

[Victor Erminpour <victor.erminpour@oracle.com>]

On 4/10/20 1:09 AM, Ard Biesheuvel wrote:
> On Thu, 9 Apr 2020 at 23:44, Victor Erminpour
> <victor.erminpour@oracle.com> 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@oracle.com>
>> ---
>>   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