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From: Arnd Bergmann <arnd@arndb.de>
To: Kees Cook <keescook@chromium.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Laura Abbott <laura@labbott.name>, Mark Rutland <mark.rutland@arm.com>,
        Jeremy Linton <jeremy.linton@arm.com>,
        Ard Biesheuvel <ard.biesheuvel@linaro.org>,
        kernel-hardening@lists.openwall.com, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] lkdtm: add test for executing .rodata
Date: Wed, 17 Feb 2016 22:45:49 +0100
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On Wednesday 17 February 2016 22:44:12 Arnd Bergmann wrote:
> On Tuesday 16 February 2016 13:49:04 Kees Cook wrote:
> >  }
> >  
> > +static void __attribute__((__section__(".rodata,\"a\",@progbits#")))
> > +do_nothing_rodata(void)
> > +{
> > +       return;
> > +}
> > +
> >  static void do_nothing(void)
> >  {
> > 
> 
> I think this also needs to be marked "noinline" to ensure that the
> function does not get eliminated. I've seen clang do that on
> execute_location() recently and submitted a patch for that.

Nevermind, this gets passed by reference into execute_location(),
so it's enough if that is marked noinline, but do_nothing_rodata
needs no such annotation.

	Arnd