Re: [PATCH v2 10/28] kbuild: lto: fix module versioning

Kees Cook
2020-09-03T22:12:17Z

On Thu, Sep 03, 2020 at 01:30:35PM -0700, Sami Tolvanen wrote:
> With CONFIG_MODVERSIONS, version information is linked into each
> compilation unit that exports symbols. With LTO, we cannot use this
> method as all C code is compiled into LLVM bitcode instead. This
> change collects symbol versions into .symversions files and merges
> them in link-vmlinux.sh where they are all linked into vmlinux.o at
> the same time.
>
> Signed-off-by: Sami Tolvanen <samitolvanen@google.com>

The only thought I have here is I wonder if this change could be made
universally instead of gating on LTO? (i.e. is it noticeably slower to
do it this way under non-LTO?)

Reviewed-by: Kees Cook <keescook@chromium.org>

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Kees Cook