From: Sven Joachim <svenjoac@gmx.de>
To: Tomas Janousek <tomi@nomi.cz>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
        Joe Perches <joe@perches.com>, Adam Borowski <kilobyte@angband.pl>,
        Michal Marek <mmarek@suse.com>, linux-kbuild@vger.kernel.org,
        linux-kernel@vger.kernel.org, ben@decadent.org.uk
Subject: Re: [RFC PATCH] kbuild: add -fno-PIE
References: <20161021111600.9417-1-bigeasy@linutronix.de>
        <20161021212127.GA32611@angband.pl> <87eg37niky.fsf@turtle.gmx.de>
        <1477250598.3561.4.camel@perches.com> <8760oinqly.fsf@turtle.gmx.de>
        <20161024074332.uomcxyhqo6aq7vxk@linutronix.de>
        <874m41mz4h.fsf@turtle.gmx.de>
        <20161029101007.zwqv3lslbzd4urco@nomi.cz>
Date: Sat, 29 Oct 2016 19:03:30 +0200
In-Reply-To: <20161029101007.zwqv3lslbzd4urco@nomi.cz> (Tomas Janousek's
        message of "Sat, 29 Oct 2016 12:10:08 +0200")
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On 2016-10-29 12:10 +0200, Tomas Janousek wrote:

> On Mon, Oct 24, 2016 at 07:32:30PM +0200, Sven Joachim wrote:
>> The attached patch works for me with Debian's gcc-6 package.
>
> I tried your patch when building 4.8.5 on an up-to-date Debian testing and
> still got this:
>
>   AS      arch/x86/entry/vdso/vdso32/note.o
> arch/x86/entry/vdso/vdso32/note.S:1:0: sorry, unimplemented: -mfentry
> isn’t supported for 32-bit in combination with -fpic

I cannot reproduce that, FWIW.  Also, arch/x86/entry/vdso/Makefile seems
to explicitly filter out -mfentry from the compiler flags, but maybe I
misunderstand something.

Could you please show the exact command that's failing with "make V=1"?

> Adding KBUILD_AFLAGS += $(call cc-option,-fno-pie,) helps.
> (Maybe that should be as-option instead. Don't know. There are lots of
> AFLAGS=$(call cc-option, ...) in the Makefiles, anyway.)

This is what Ubuntu is doing, so it works at least for them, I suppose.

Cheers,
       Sven