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Date: Mon, 7 Oct 2002 14:51:52 -0600
From: Michal Jaegermann <michal@harddata.com>
To: linux-kernel@vger.kernel.org
Subject: Is this racy?
Message-ID: <20021007145152.A4065@mail.harddata.com>
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In fs/proc/array.c (2.4.20-pre9, 2.4.19 and likely many other
versions) in function 'proc_pid_stat()' there is a code like that:

	......
	read_lock(&tasklist_lock);
	ppid = task->pid ? task->p_opptr->pid : 0;
	read_unlock(&tasklist_lock);
	res = sprintf(buffer,"<long format string>",
		task->pid,
		......
		ppid,
		......

So assignment to ppid is locked but other reads from fiels of 'task'
structure are not guarded that way.  Is this ok or if not we do not
particularly care?  Function 'task_state()' in the same file seems
to be more careful about this.

  Michal