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Subject: Re: [PATCH v3] add param that allows bootline control of hardened
 usercopy
To:     Kees Cook <keescook@chromium.org>
Cc:     Laura Abbott <labbott@redhat.com>, Paolo Abeni <pabeni@redhat.com>,
        LKML <linux-kernel@vger.kernel.org>,
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From:   Christoph von Recklinghausen <crecklin@redhat.com>
Organization: Red Hat
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Date:   Mon, 2 Jul 2018 14:55:35 -0400
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On 07/02/2018 02:43 PM, Kees Cook wrote:
> On Sat, Jun 30, 2018 at 1:43 PM, Christoph von Recklinghausen
> <crecklin@redhat.com> wrote:
>> The last issue I'm chasing is build failures on ARCH=m68k. The error is
>> atomic_read and friends needed by the jump label code not being found.
>> The config has CONFIG_BROKEN_ON_SMP=y, so the jump label calls I added
>> will only be made #ifndef CONFIG_BROKEN_ON_SMP. Do you think that's
>> worth a mention in the blurb that's added to
>> Documentation/admin-guide/kernel-parameters.txt?
> Uhm, that's weird -- I think the configs on m68k need fixing then? I
> don't want to have to sprinkle that ifdef in generic code.
>
> How are other users of static keys and jump labels dealing with m68k weirdness?
>
> -Kees
>
There's also CONFIG_JUMP_LABEL which is defined in x86_64 but not
defined in the m68k configs. I'll use that instead. In hindsight I
should have spotted that but didn't.

Thanks,

Chris