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Subject: Re: Is in_le32 and out_le32 atomic?
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Wolfgang Grandegger <wg@grandegger.com>
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> Can anybody tell me why the spin_* protection is needed? I thought that 
> 32-bit read and write operations are atomic.

It doesn't seem to make sense indeed...

Ben.