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Date: Tue, 14 Jun 2016 16:34:22 +0200
From: Oleg Nesterov <oleg@redhat.com>
To: Andy Lutomirski <luto@amacapital.net>
Cc: Dmitry Safonov <dsafonov@virtuozzo.com>, "H. Peter Anvin" <hpa@zytor.com>,
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        X86 ML <x86@kernel.org>, Ingo Molnar <mingo@redhat.com>
Subject: Re: [PATCH 5/6] x86/ptrace: down with test_thread_flag(TIF_IA32)
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On 06/13, Andy Lutomirski wrote:
>
> On Mon, Jun 13, 2016 at 6:50 AM, Oleg Nesterov <oleg@redhat.com> wrote:
> >
> > Well, I can't resist but to me SA_IA32_ABI/SA_X32_ABI looks like a hack
> > too.  We actually shift TIF_*32 into k_sigaction->flags, and the fact
> > that we do this per-signal looks, well, interesting ;)
>
> Is anything actually wrong with this, though?

No, I think the patch is correct... It adds the user-visible change, but
I do not think it can break something.

Well, perhaps we should also remove SA_IA32_ABI|SA_X32_ABI from
oact->sa.sa_flags in do_sigaction() to ensure that these non-uapi flags won't
leak to user-space, but probably we do not really care.

Oleg.