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Date: Tue, 15 Feb 2011 16:24:48 +0100
From: Tejun Heo <tj@kernel.org>
To: Oleg Nesterov <oleg@redhat.com>
Cc: Denys Vlasenko <vda.linux@googlemail.com>,
        Roland McGrath <roland@redhat.com>, jan.kratochvil@redhat.com,
        linux-kernel@vger.kernel.org, torvalds@linux-foundation.org,
        akpm@linux-foundation.org
Subject: Re: [PATCH 1/1] ptrace: make sure do_wait() won't hang after
 PTRACE_ATTACH
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Hello, Oleg, Denys.

On Mon, Feb 14, 2011 at 09:01:30PM +0100, Oleg Nesterov wrote:
> > Or we can avoid entering TASK_TRACED on ptrace(PTRACE_GETSIGINFO) et al.
> > Can we remain in TASK_STOPPED?
> 
> Oh, unlikely, I think.

Actually I was thinking along this line.  We can allow
PTRACE_GETSIGINFO to proceed without forcing the tracee into TRACED
state, the rationale being the operation is required to tell between
group stop and ptrace trap.  Am I missing something?

Thanks.

-- 
tejun
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