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Date: Wed, 29 Feb 2012 11:51:49 -0600
Message-ID: <CABqD9haTSHdAcGBy4kLrhAs4UFSrMPFNsLC+X-Hf5_ud2_w19Q@mail.gmail.com>
Subject: Re: [PATCH v11 10/12] ptrace,seccomp: Add PTRACE_SECCOMP support
From: Will Drewry <wad@chromium.org>
To: Roland McGrath <mcgrathr@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>, linux-kernel@vger.kernel.org,
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On Wed, Feb 29, 2012 at 11:41 AM, Roland McGrath <mcgrathr@google.com> wrote:
> I don't think TIF_NOTIFY_RESUME is apropos here.  That only triggers on
> returning to user mode, i.e. after syscall exit.  But regardless of the
> exact implementation details, I don't think it will be prohibitive to add
> some means by which the fast-path can back off before actual syscall entry
> and go to the slow path for ptrace reporting.
>
> Since there is no strong reason to think it can't be reorganized that way
> later, I don't see any good rationale for constraining the seccomp-filter
> feature definition based on a plan to optimize the implementation in the
> future.

Sounds good to me.   I'll move to ptrace_event and save the problem of
code organization for the future.

Thanks!