linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Lecopzer Chen <lecopzer.chen@mediatek.com>
To: <ndesaulniers@google.com>, <keescook@chromium.org>,
	<samitolvanen@google.com>, <linux-kbuild@vger.kernel.org>,
	<nathan@kernel.org>
Cc: <clang-built-linux@googlegroups.com>,
	<linux-kernel@vger.kernel.org>, <yj.chiang@mediatek.com>,
	<masahiroy@kernel.org>, <michal.lkml@markovi.net>,
	Lecopzer Chen <lecopzer.chen@mediatek.com>
Subject: [PATCH v3 0/2] Kbuild: lto: add make version checking for MODVERSIONS
Date: Fri, 2 Jul 2021 11:29:41 +0800	[thread overview]
Message-ID: <20210702032943.7865-1-lecopzer.chen@mediatek.com> (raw)

LTO with MODVERSIONS will fail in generating correct CRC because
the makefile rule doesn't work for make with version 3.8X.

Refer to [1]:
> When building modules(CONFIG_...=m), I found some of module versions
> are incorrect and set to 0.
> This can be found in build log for first clean build which shows

> WARNING: EXPORT symbol "XXXX" [drivers/XXX/XXX.ko] version generation failed,
> symbol will not be versioned.

> But in second build(incremental build), the WARNING disappeared and the
> module version becomes valid CRC and make someone who want to change
> modules without updating kernel image can't insert their modules.

> The problematic code is
> + $(foreach n, $(filter-out FORCE,$^),        \
> +   $(if $(wildcard $(n).symversions),      \
> +     ; cat $(n).symversions >> $@.symversions))

The issue is fixed when make version upgrading to 4.2.

Thus we need to check make version during selecting on LTO Kconfig.
Add CONFIG_MAKE_VERSION which means MAKE_VERSION in canonical digits
for arithmetic comparisons.

[1] https://lore.kernel.org/lkml/20210616080252.32046-1-lecopzer.chen@mediatek.com/
Signed-off-by: Lecopzer Chen <lecopzer.chen@mediatek.com>


----
v3:
- fix comment in make-version.sh

v2:
https://lore.kernel.org/lkml/20210701092841.1419-1-lecopzer.chen@mediatek.com/
- change MAKE_VERSION_INT to MAKE_VERSION
- remove $(make-version)
- tweak commit message

v1:
https://lore.kernel.org/lkml/20210630121436.19581-1-lecopzer.chen@mediatek.com/
----


Lecopzer Chen (2):
  Kbuild: lto: add CONFIG_MAKE_VERSION
  Kbuild: lto: add make version checking

 Makefile                |  2 +-
 arch/Kconfig            |  1 +
 init/Kconfig            |  4 ++++
 scripts/make-version.sh | 13 +++++++++++++
 4 files changed, 19 insertions(+), 1 deletion(-)
 create mode 100755 scripts/make-version.sh

-- 
2.18.0


             reply	other threads:[~2021-07-02  3:29 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-07-02  3:29 Lecopzer Chen [this message]
2021-07-02  3:29 ` [PATCH v3 1/2] Kbuild: lto: add CONFIG_MAKE_VERSION Lecopzer Chen
2021-07-04  0:15   ` Nathan Chancellor
2021-07-05  2:02   ` Masahiro Yamada
2021-07-05 17:59     ` Sami Tolvanen
2021-07-06  9:06       ` Lecopzer Chen
2021-07-07 17:02         ` Sami Tolvanen
2021-07-09  8:25           ` Lecopzer Chen
2021-07-02  3:29 ` [PATCH v3 2/2] Kbuild: lto: add make version checking Lecopzer Chen
2021-07-04  0:16   ` Nathan Chancellor
2021-07-05  2:04   ` Masahiro Yamada

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20210702032943.7865-1-lecopzer.chen@mediatek.com \
    --to=lecopzer.chen@mediatek.com \
    --cc=clang-built-linux@googlegroups.com \
    --cc=keescook@chromium.org \
    --cc=linux-kbuild@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=masahiroy@kernel.org \
    --cc=michal.lkml@markovi.net \
    --cc=nathan@kernel.org \
    --cc=ndesaulniers@google.com \
    --cc=samitolvanen@google.com \
    --cc=yj.chiang@mediatek.com \
    --subject='Re: [PATCH v3 0/2] Kbuild: lto: add make version checking for MODVERSIONS' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).