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From: Roland McGrath <roland@redhat.com>
To: Frederic Weisbecker <fweisbec@gmail.com>
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Cc: Oleg Nesterov <oleg@redhat.com>, Alan Stern <stern@rowland.harvard.edu>,
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        Peter Zijlstra <a.p.zijlstra@chello.nl>,
        Prasad <prasad@linux.vnet.ibm.com>, linux-kernel@vger.kernel.org
Subject: Re: Q: perf_event && task->ptrace_bps[]
In-Reply-To: Frederic Weisbecker's message of  Tuesday, 18 January 2011 00:58:30 +0100 <20110117235828.GE16856@nowhere>
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Date: Mon, 17 Jan 2011 17:16:00 -0800 (PST)
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> Aah, so we check if the task is stopped when sys_ptrace() is called,
> but right after we do this check, the tracee can be resumed at any time?
> (with either SIGCONT or SIGKILL), even if we are servicing the ptrace
> request at the same time?

Only by SIGKILL.