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Date: Tue, 3 May 2011 16:55:20 +1000
From: Anton Blanchard <anton@samba.org>
To: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Subject: Re: [PATCH] powerpc: Add Initiate Coprocessor Store Word (icswx)
	support
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Hi Ben,

> My only comment (sorry Anton :-) would have been that we could lazily
> allocate the spinlock on the first use_cop() ... or do we have that
> potentially called in the wrong context ?

I worry what might happen in a threaded app. It would be a strange
thing to do, but the program may call use_cop from two threads at the
same time. In that case you could corrupt the PID/ACOP values
and leak a spinlock of memory I think.

Anton