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Date: Tue, 15 Oct 2013 08:04:25 +0200
From: Ingo Molnar <mingo@kernel.org>
To: Kees Cook <keescook@chromium.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>, LKML <linux-kernel@vger.kernel.org>,
        Michael Davidson <md@google.com>, Thomas Gleixner <tglx@linutronix.de>,
        "H. Peter Anvin" <hpa@linux.intel.com>,
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Subject: Re: [tip:x86/kaslr] x86, relocs: Add more per-cpu gold special cases
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* Kees Cook <keescook@chromium.org> wrote:

> On Mon, Oct 14, 2013 at 9:28 AM, H. Peter Anvin <hpa@zytor.com> wrote:
> > On 10/14/2013 07:19 AM, H. Peter Anvin wrote:
> >> My guess is that the 95 addresses are randomized and the 82 address is an address which failed to relocate.
> >
> >> ffffffff82a04a58 is:
> >> ffffffff82a03000 t init_per_cpu__gdt_page
> >
> >
> > Specifically, it looks like the percpu stuff isn't getting set up correctly.
> 
> It wouldn't surprise me if there are even more percpu things to fix.
> It's the main area we've continued to trip over while working on this
> with various linkers. Which linker and version are you seeing this
> with?

The failure I saw triggered with fairly modern userspace:

 GNU ld version 2.23.52.0.1-9.fc19 20130226

 gcc version 4.8.1 20130603 (Red Hat 4.8.1-1) (GCC) 

Thanks,

	Ingo