Re: [PATCH] arm64 module: remove (NOLOAD)

From: Ard Biesheuvel
Date: Fri Feb 18 2022 - 03:18:04 EST


On Fri, 18 Feb 2022 at 09:12, Fangrui Song <maskray@xxxxxxxxxx> wrote:
>
> On ELF, (NOLOAD) sets the section type to SHT_NOBITS[1]. It is conceptually
> inappropriate for .plt and .text.* sections which are always
> SHT_PROGBITS.
>
> In GNU ld, if PLT entries are needed, .plt will be SHT_PROGBITS anyway
> and (NOLOAD) will be essentially ignored. In ld.lld, since
> https://reviews.llvm.org/D118840 ("[ELF] Support (TYPE=<value>) to
> customize the output section type"), ld.lld will report a `section type
> mismatch` error. Just remove (NOLOAD) to fix the error.
>
> [1] https://lld.llvm.org/ELF/linker_script.html As of today, "The
> section should be marked as not loadable" on
> https://sourceware.org/binutils/docs/ld/Output-Section-Type.html is
> outdated for ELF.

This patch lacks a SOB line.

With one added,

Acked-by: Ard Biesheuvel <ardb@xxxxxxxxxx>

> ---
> arch/arm64/include/asm/module.lds.h | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/arch/arm64/include/asm/module.lds.h b/arch/arm64/include/asm/module.lds.h
> index a11ccadd47d2..094701ec5500 100644
> --- a/arch/arm64/include/asm/module.lds.h
> +++ b/arch/arm64/include/asm/module.lds.h
> @@ -1,8 +1,8 @@
> SECTIONS {
> #ifdef CONFIG_ARM64_MODULE_PLTS
> - .plt 0 (NOLOAD) : { BYTE(0) }
> - .init.plt 0 (NOLOAD) : { BYTE(0) }
> - .text.ftrace_trampoline 0 (NOLOAD) : { BYTE(0) }
> + .plt 0 : { BYTE(0) }
> + .init.plt 0 : { BYTE(0) }
> + .text.ftrace_trampoline 0 : { BYTE(0) }
> #endif
>
> #ifdef CONFIG_KASAN_SW_TAGS
> --
> 2.35.1.265.g69c8d7142f-goog
>