Re: [PATCH] module: Remove unused DISCARD_EH_FRAME definition from module.lds.S

[Sami Tolvanen]

On Fri, Jun 12, 2026 at 6:40 AM Petr Pavlu <petr.pavlu@xxxxxxxx> wrote:
>
> The linker script scripts/module.lds.S contains an unused DISCARD_EH_FRAME
> definition introduced by commit 68c76ad4a957 ("arm64: unwind: add
> asynchronous unwind tables to kernel and modules").
>
> As shown in an earlier version of that patch [1], DISCARD_EH_FRAME was
> meant to be used by SANITIZER_DISCARDS in the same file, as follows:
>
> -# define SANITIZER_DISCARDS    *(.eh_frame)
> +# define SANITIZER_DISCARDS    DISCARD_EH_FRAME
>
> However, in the meantime, SANITIZER_DISCARDS was removed entirely from
> module.lds.S by commit 89245600941e ("cfi: Switch to -fsanitize=kcfi").
> Eventually, the mentioned commit 68c76ad4a957 only added the new
> DISCARD_EH_FRAME definition to this file without actually using it.
>
> The file include/asm-generic/vmlinux.lds.h contains a similar
> DISCARD_EH_FRAME definition for vmlinux to discard .eh_frame sections that
> may be present when CONFIG_GCOV_KERNEL, CONFIG_KASAN_GENERIC or
> CONFIG_KCSAN is enabled. Testing these options on arm64 with LLVM 19.1 did
> not show any unexpected .eh_frame sections in modules.
>
> Remove the unused DISCARD_EH_FRAME definition from scripts/module.lds.S.
>
> Link: https://lore.kernel.org/linux-arm-kernel/20220701152724.3343599-2-ardb@xxxxxxxxxx/ [1]
> Signed-off-by: Petr Pavlu <petr.pavlu@xxxxxxxx>

Reviewed-by: Sami Tolvanen <samitolvanen@xxxxxxxxxx>

Sami