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Date: Mon, 10 May 2010 13:54:17 -0700
From: Dmitry Torokhov <dmitry.torokhov@gmail.com>
To: Mike Frysinger <vapier.adi@gmail.com>
Cc: Oskar Schirmer <os@emlix.com>,
       Michael Hennerich <Michael.Hennerich@analog.com>,
       Andrew Morton <akpm@linux-foundation.org>, linux-input@vger.kernel.org,
       linux-kernel@vger.kernel.org,
       Daniel =?iso-8859-1?Q?Gl=F6ckner?= <dg@emlix.com>,
       Oliver Schneidewind <osw@emlix.com>, Johannes Weiner <jw@emlix.com>
Subject: Re: [PATCH v3] ad7877: keep dma rx buffers in seperate cache lines
Message-ID: <20100510205416.GB30878@core.coreip.homeip.net>
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On Mon, May 10, 2010 at 12:39:49PM -0400, Mike Frysinger wrote:
> On Mon, May 10, 2010 at 06:42, Oskar Schirmer wrote:
> > With dma based spi transmission, data corruption
> > is observed occasionally. With dma buffers located
> > right next to msg and xfer fields, cache lines
> > correctly flushed in preparation for dma usage
> > may be polluted again when writing to fields
> > in the same cache line.
> >
> > Make sure cache fields used with dma do not
> > share cache lines with fields changed during
> > dma handling. As both fields are part of a
> > struct that is allocated via kzalloc, thus
> > cache aligned, moving the fields to the 1st
> > position and insert padding for alignment
> > does the job.
> 
> Acked-by: Mike Frysinger <vapier@gentoo.org>
> 
> i'm guessing Dmitry will pick it up now

Yep.

-- 
Dmitry