[PATCH 3/7] Makefile.lib: Preserve .rodata section for EFI file

[Heinrich Schuchardt]

On 11.06.24 16:06, Jiaxun Yang wrote:
>
>
> 在2024年6月11日六月 下午2:49，Ilias Apalodimas写道：
>> Hi Jiaxun
>>
>>
>> On Fri, 17 May 2024 at 19:33, Jiaxun Yang <jiaxun.yang at flygoat.com> wrote:
>>>
>>> This is required in performing objcopy to MIPS EFI files.
>>>
>>
>> This seems not mips specific. What was missing for your case?
>
> So MIPS EFI file would come with .rodata section. If we don't preserve
> it here, the whole section would be stripped away.
>
> .rodata is always necessary in binary if it's in ELF as it contains
> valid program data.
>
> Other architectures won't generate .rodata section in their ELF file
> so it's harmless. Besides GNU-EFI's universal strip commands also have
> -j .rodata argument.
>
> Thanks
> - Jiaxun
>>
>> Thanks
>> /Ilias
>>> Signed-off-by: Jiaxun Yang <jiaxun.yang at flygoat.com>
>>> ---
>>>   scripts/Makefile.lib | 2 +-
>>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>>
>>> diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
>>> index 62f87517c09c..52aed7a65d47 100644
>>> --- a/scripts/Makefile.lib
>>> +++ b/scripts/Makefile.lib
>>> @@ -469,7 +469,7 @@ $(obj)/%_efi.S: $(obj)/%.efi
>>>
>>>   quiet_cmd_efi_objcopy = OBJCOPY $@
>>>   cmd_efi_objcopy = $(OBJCOPY) -j .header -j .text -j .sdata -j .data -j \
>>> -               .dynamic -j .dynsym  -j .rel* -j .rela* -j .reloc \
>>> +               .dynamic -j .dynsym  -j .rel* -j .rela* -j .reloc -j .rodata \
>>>                  $(if $(EFI_TARGET),$(EFI_TARGET),-O binary) $^ $@
>>>
>>>   $(obj)/%.efi: $(obj)/%_efi.so
>>>
>>> --
>>> 2.34.1
>>>
>

We have:

arch/arm/lib/elf_aarch64_efi.lds:26:            *(.rodata*)
arch/arm/lib/elf_arm_efi.lds:26:                *(.rodata*)
arch/riscv/lib/elf_riscv32_efi.lds:26:          *(.rodata*)
arch/riscv/lib/elf_riscv64_efi.lds:26:          *(.rodata*)
arch/x86/lib/elf_ia32_efi.lds:35:               *(.rodata*)
arch/x86/lib/elf_x86_64_efi.lds:37:             *(.rodata*)

Not considering .rodata in objcopy looks inconsistent.

As we use -fdata-sections wouldn't we expect a .rodata* section per
function with constants on LoongArch? Shouldn't we use:

+ .dynamic -j .dynsym  -j .rel* -j .rela* -j .reloc -j .rodata* \

Best regards

Heinrich