From mboxrd@z Thu Jan  1 00:00:00 1970
From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Subject: Re: [PATCH] rtmutex.c: Fix incorrect waiter check
Date: Tue, 17 Feb 2015 17:10:31 +0100
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Cc: Brad Mouring <bmouring@ni.com>,
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To: Steven Rostedt <rostedt@goodmis.org>
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* Steven Rostedt | 2015-01-21 15:13:52 [-0500]:

>On Wed, 14 Jan 2015 15:11:38 -0600
>"Brad Mouring" <bmouring@ni.com> wrote:
>
>> In task_blocks_on_lock, there's a null check on pi_blocked_on
>> of the task_struct. This pointer can encode the fact that the
>> task that contains the pointer is waking (preventing requeuing)
>> and therefore is non-null. Use the inline function to avoid
>> dereferencing an invalid "pointer"
>
>Yep, this looks legit. I can apply it to the series I maintain.

I added it to v3.18 with a stable tag. I don't know why this did not
pop-up earlier or if this is part of the rtmutex re-write.

>-- Steve

Sebastian