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Date: Mon, 16 May 2011 14:24:14 +0200
From: Tejun Heo <tj@kernel.org>
To: Jan Kratochvil <jan.kratochvil@redhat.com>
Cc: Denys Vlasenko <vda.linux@googlemail.com>, Oleg Nesterov <oleg@redhat.com>,
        linux-kernel@vger.kernel.org, torvalds@linux-foundation.org,
        akpm@linux-foundation.org, indan@nul.nu
Subject: Re: PTRACE_DETACH without stop  [Re: [PATCH 04/11] ptrace:
 implement PTRACE_INTERRUPT]
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On Mon, May 16, 2011 at 02:08:22PM +0200, Jan Kratochvil wrote:
> > Nope.  What userland is currently dealing with isn't that type of
> > conditions.  It's dealing with nasty side effects of implied and
> > required signals, which will be removed with the new interface.
> 
> They won't as there will be new INTERRUPT event and when one wants to trap it
> one has to deal with various signals coming before or after it.

I'd rather lean toward handling it properly from userland.  Strictly
defining trap order is too fragile.  I think the right thing to do
here is properly documenting how to recognize and handle different
types of traps.

Thanks.

-- 
tejun
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