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Date: Wed, 24 Oct 2012 18:18:36 +0530
Message-ID: <CAAHN_R0jTey+4TOXfKh96aApOPUXQq6wwobejmhFeRuTV2VJKA@mail.gmail.com>
Subject: Re: [PATCH] [RESEND 2] Take over futex of dead task only if
 FUTEX_WAITERS is not set
From: Siddhesh Poyarekar <siddhesh.poyarekar@gmail.com>
To: Thomas Gleixner <tglx@linutronix.de>
Cc: Darren Hart <dvhart@linux.intel.com>, LKML <linux-kernel@vger.kernel.org>,
        Ingo Molnar <mingo@kernel.org>, Peter Zijlstra <peterz@infradead.org>
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> Now there is a different solution to that problem. Do not look at the
> user space value at all and enforce a lookup of possibly available
> pi_state. If pi_state can be found, then the new incoming locker T3
> blocks on that pi_state and legitimately races with T2 to acquire the
> rt_mutex and the pi_state and therefor the proper ownership of the
> user space futex.

That works. Thanks for the detailed explanation too.


-- 
http://siddhesh.in