Re: [PATCH v2] kbuild: fix UNUSED_KSYMS_WHITELIST for Clang LTO
From: Masahiro Yamada
Date: Sat Feb 27 2021 - 01:57:23 EST
On Fri, Feb 26, 2021 at 6:26 PM Sedat Dilek <sedat.dilek@xxxxxxxxx> wrote:
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On Fri, Feb 26, 2021 at 7:26 AM Masahiro Yamada <masahiroy@xxxxxxxxxx> wrote:
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> Commit fbe078d397b4 ("kbuild: lto: add a default list of used symbols")
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> does not work as expected if the .config file has already specified
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> CONFIG_UNUSED_KSYMS_WHITELIST="my/own/white/list" before enabling
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> CONFIG_LTO_CLANG.
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> So, the user-supplied whitelist and LTO-specific white list must be
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> independent of each other.
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> I refactored the shell script so CONFIG_MODVERSIONS and CONFIG_CLANG_LTO
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> handle whitelists in the same way.
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> Fixes: fbe078d397b4 ("kbuild: lto: add a default list of used symbols")
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> Signed-off-by: Masahiro Yamada <masahiroy@xxxxxxxxxx>
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> ---
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> Changes in v2:
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> - Rebase on top of Arnd's patch:
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> https://lore.kernel.org/lkml/20210225143456.3829513-1-arnd@xxxxxxxxxx/
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> init/Kconfig | 1 -
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> scripts/gen_autoksyms.sh | 35 ++++++++++++++++++++++++---------
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> scripts/lto-used-symbollist.txt | 6 ------
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People who want to use their own "white-listed" (allow-listed)
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symbollist-file can do that via
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CONFIG_UNUSED_KSYMS_WHITELIST="my/own/white/list".
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Correct?
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Why do you delete the default "scripts/lto-used-symbollist.txt" file
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and remove the default in the appropriate Kconfig for people who want
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to enable Clang-(Thin)LTO?
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These people should now use
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CONFIG_UNUSED_KSYMS_WHITELIST="scripts/lto-used-symbollist.txt"?
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But again - the file was deleted with your patch.
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Do I miss something?
I think so.
I moved those symbols to scripts/gen_autoksyms.sh
--
Best Regards
Masahiro Yamada