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Date: Mon, 16 May 2011 15:54:14 +0200
From: Tejun Heo <tj@kernel.org>
To: Jan Kratochvil <jan.kratochvil@redhat.com>
Cc: oleg@redhat.com, vda.linux@googlemail.com, linux-kernel@vger.kernel.org,
        torvalds@linux-foundation.org, akpm@linux-foundation.org, indan@nul.nu
Subject: Re: PTRACE_SEIZE should not stop  [Re: [PATCH 02/11] ptrace:
 implement PTRACE_SEIZE]
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Hello,

On Mon, May 16, 2011 at 03:48:08PM +0200, Jan Kratochvil wrote:
> On Mon, 16 May 2011 15:45:10 +0200, Tejun Heo wrote:
> > I don't think INTERRUPT can be prioritized like that above existing
> > trap conditions.  Traps are taken sometimes deep in the kernel
> > (e.g. fork/exec) and often after modifying states irrevocably
> > (e.g. signal is already dequeued on signal trap).  I don't think how
> > it would be possible to rewind the state changes and replay it later.
> 
> OK, so that closes one of the major issues I was trying to get "fixed".

Sorry, this one was too difficult and, even if somehow I pulled it,
unlikely to make upstream.  It's gonna be extremely fragile.
Unfortunately, userland would still have to deal with arbitrary order
of traps.

Thank you.

-- 
tejun
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