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From:   Nick Desaulniers <ndesaulniers@google.com>
Date:   Fri, 25 May 2018 13:36:26 -0700
Message-ID: <CAKwvOdkWsxoyXCnQz+Xwh0RQ0yPPVD3iCqVaWAimW_Z4QU0XiA@mail.gmail.com>
Subject: Re: [clang] stack protector and f1f029c7bf
To:     hpa@zytor.com
Cc:     Alistair Strachan <astrachan@google.com>,
        Manoj Gupta <manojgupta@google.com>,
        Matthias Kaehlcke <mka@google.com>,
        Greg Hackmann <ghackmann@google.com>, sedat.dilek@gmail.com,
        tstellar@redhat.com, LKML <linux-kernel@vger.kernel.org>,
        Kees Cook <keescook@google.com>
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On Fri, May 25, 2018 at 10:56 AM <hpa@zytor.com> wrote:
> You need the extern inline in the .h file and the out-of-line .S file
both.

But the out-of-line .S file looks like:

...
    10 ENTRY(native_save_fl)

    11   pushf

    12   pop %_ASM_AX

    13   ret

    14 ENDPROC(native_save_fl)

    15 EXPORT_SYMBOL(native_save_fl)
...

I don't see how you can specify to the linker from assembly source that
this function should be treated as `extern inline`?

I assume you don't literally mean the C keywords `extern inline` but
whatever the equivalent incantation is needed in terms of assembler
directives (which I also don't know).

I'm beginning to think that what you'd like to see cannot be expressed (at
least via `extern inline`).
--
Thanks,
~Nick Desaulniers