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Date: Wed, 12 Jan 2011 21:41:36 +0100
From: Jan Kratochvil <jan.kratochvil@redhat.com>
To: Tejun Heo <tj@kernel.org>
Cc: oleg@redhat.com, roland@redhat.com, linux-kernel@vger.kernel.org,
        rjw@sisk.pl
Subject: Re: [PATCH 1/4] signal: fix SIGCONT notification code
Message-ID: <20110112204136.GB13830@host1.dyn.jankratochvil.net>
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On Wed, 22 Dec 2010 12:13:15 +0100, Tejun Heo wrote:
> If SIGCONT is received while the child process is stopped, the code should
> be CLD_CONTINUED.  If SIGCONT is recieved while the child process is in the
> process of being stopped, it should be CLD_STOPPED.

If a process does
	kill (PID, SIGSTOP);
	<varying delay, possibly even from a different process>
	kill (PID, SIGCONT);

does it mean the PID's parent may get different waitid() results?
Or even that PID will finally remain still `T (stopped)'?

I do not see it has any userland impact, the
PTRACE_ATTACH-to-T(stopped)-process is already racy for different reasons.


Thanks,
Jan