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Date: Mon, 6 Jun 2011 22:49:23 +0300
From: Dan Carpenter <error27@gmail.com>
To: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: anish <anish198519851985@gmail.com>, devel@driverdev.osuosl.org,
        arnd@arndb.de, lucas.demarchi@profusion.mobi, gregkh@suse.de,
        linux-kernel@vger.kernel.org, jic23@cam.ac.uk,
        manuel.stahl@iis.fraunhofer.de
Subject: Re: [PATCH 1/2] staging: iio replaced kmalloc with local variables.
Message-ID: <20110606194923.GC3846@shale.localdomain>
References: <1307387257.4327.12.camel@anish-desktop>
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On Mon, Jun 06, 2011 at 09:13:29PM +0200, Geert Uytterhoeven wrote:
> On Mon, Jun 6, 2011 at 21:07, anish <anish198519851985@gmail.com> wrote:
> > From: anish kumar <anish198519851985@gmail.com>
> >
> > Replace kmalloc with local variables as it was un-necessary and
> 
> Is it really unnecessary?
> Or is this hardware that cannot transfer buffers on the stack?
> IIRC there have been similar problems with SCSI command buffers on the stack.

Yes.  You're right.  These buffers are not allowed to be stack
memory.  The documentation is the section "What memory is DMA'able?"
in Documentation/DMA-API-HOWTO.txt.

regards,
dan carpenter