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From: Andy Lutomirski <luto@amacapital.net>
Date: Tue, 14 Mar 2017 12:23:40 -0700
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Subject: Re: [PATCH v10 6/7] x86/arch_prctl: Add ARCH_[GET|SET]_CPUID
To: "H. Peter Anvin" <hpa@zytor.com>
Cc: Kyle Huey <me@kylehuey.com>,
        "Robert O'Callahan" <robert@ocallahan.org>,
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On Tue, Mar 14, 2017 at 12:01 PM, H. Peter Anvin <hpa@zytor.com> wrote:
> and at least theoretically we
> could be indirecting though the ->stack pointer for every one if gcc
> can't tell it won't have changed (we really need to get thread_info
> moved into the task_struct allocation and away from the kernel stack,
> especially since on x86 the pointer is the same size as the vestigial
> structure it points to.)

Solved by use of time machine:

commit 15f4eae70d365bba26854c90b6002aaabb18c8aa
Author: Andy Lutomirski <luto@kernel.org>
Date:   Tue Sep 13 14:29:25 2016 -0700

    x86: Move thread_info into task_struct


:)