Re: [PATCH v3 1/4] x86/xen.lds.S: Work around binutils build id alignment bug

[Jan Beulich <jbeulich@xxxxxxxx>]

On 07.09.2020 21:00, Trammell Hudson wrote:
> --- a/xen/arch/x86/xen.lds.S
> +++ b/xen/arch/x86/xen.lds.S
> @@ -156,6 +156,7 @@ SECTIONS
>         __note_gnu_build_id_end = .;
>    } :note :text
>  #elif defined(BUILD_ID_EFI)
> +  . = ALIGN(32); /* workaround binutils section overlap bug */
>    DECL_SECTION(.buildid) {
>         __note_gnu_build_id_start = .;
>         *(.buildid)

It being "just" 32 bytes may make it look as if we could take this
without much thinking, but I'm then struggling where we would draw
the boundary. The binutils bug having got fixed (or at least worked
around), I don't really like this getting applied uniformly, the
more that nothing would normally have the requirement you have (to
be able to objcopy the whole thing).

Personally I think this kind of a workaround patch is something
distros ought to be fine to carry, if they care about the
functionality and only until they get around to upgrade their
binutils. But I'll be happy to hear differing opinions.

I also don't see any mention anywhere of why it's 32 bytes, and not
16 or 64 or yet something else.

Finally, please Cc maintainers on patch submissions.

Jan