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Date: Tue, 9 Aug 2016 16:08:38 -0600
From: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
To: Dmitry Torokhov <dtor@chromium.org>
Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>,
        Christophe Ricard <christophe.ricard@gmail.com>,
        tpmdd-devel@lists.sourceforge.net,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [tpmdd-devel] [PATCH] tpm: fix cacheline alignment for DMA-able
 buffers
Message-ID: <20160809220837.GA5535@obsidianresearch.com>
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On Tue, Aug 09, 2016 at 08:18:00AM -0700, Dmitry Torokhov wrote:

>    Well, the main reason was simplicity and invasiveness of the
>    change.

Well, it isn't simple, because the proposed patches have had subtle
problems with DMA. Simple is to use a guaranteed dma-able allocation
for DMA memory and stop trying to over optimize.

Jason