Re: [PATCH v2 15/28] init: lto: ensure initcall ordering

David Woodhouse
2020-09-10T09:29:02Z

[-- Attachment #1: Type: text/plain, Size: 876 bytes --]

On Thu, 2020-09-03 at 13:30 -0700, Sami Tolvanen wrote:
> With LTO, the compiler doesn't necessarily obey the link order for
> initcalls, and initcall variables need globally unique names to avoid
> collisions at link time.
>
> This change exports __KBUILD_MODNAME and adds the initcall_id() macro,
> which uses it together with __COUNTER__ and __LINE__ to help ensure
> these variables have unique names, and moves each variable to its own
> section when LTO is enabled, so the correct order can be specified using
> a linker script.
>
> The generate_initcall_ordering.pl script uses nm to find initcalls from
> the object files passed to the linker, and generates a linker script
> that specifies the intended order. With LTO, the script is called in
> link-vmlinux.sh.

Is this guaranteed to give you the *same* initcall ordering with LTO as
without?

[-- Attachment #2: smime.p7s --]
[-- Type: application/x-pkcs7-signature, Size: 5174 bytes --]