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Date:   Fri, 9 Feb 2018 15:00:41 -0800
From:   Andi Kleen <ak@linux.intel.com>
To:     Chris Wilson <chris@chris-wilson.co.uk>
Cc:     Arnd Bergmann <arnd@arndb.de>, x86@kernel.org,
        Nicolas Pitre <nico@linaro.org>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 0/3] x86 bugfixes for LTO
Message-ID: <20180209230041.GI10945@tassilo.jf.intel.com>
References: <20180202145434.100626-1-arnd@arndb.de>
 <151821507347.9954.4785393248908071074@mail.alporthouse.com>
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On Fri, Feb 09, 2018 at 10:24:33PM +0000, Chris Wilson wrote:
> Quoting Arnd Bergmann (2018-02-02 14:54:28)
> > Here are three bugfixes for x86 that I needed to get LTO-enabled
> > kernels to build reliably. I'm not sure abouto that first one
> > though.
> 
> Is there a howto on how to build LTO kernels? I tried Andi's lto-415-2
> branch, but linking fails with lots of arcane PIE-vs-PIC errors. We are
> wanting to investigate how we can use LTO to reduce our (i915.ko) module
> size (by e.g. supporting a subset of chipsets).

What are the errors? Kernel shouldn't use PIE or PIC

-Andi