lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <20160531132706.GC29837@sirena.org.uk>
Date:	Tue, 31 May 2016 14:27:07 +0100
From:	Mark Brown <broonie@...nel.org>
To:	Michal Suchanek <hramrach@...il.com>
Cc:	Geert Uytterhoeven <geert@...ux-m68k.org>,
	linux-sunxi <linux-sunxi@...glegroups.com>,
	Maxime Ripard <maxime.ripard@...e-electrons.com>,
	Chen-Yu Tsai <wens@...e.org>,
	linux-spi <linux-spi@...r.kernel.org>,
	"linux-arm-kernel@...ts.infradead.org" 
	<linux-arm-kernel@...ts.infradead.org>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH 5/5] RFC spi: sun4i: add DMA support

On Tue, May 31, 2016 at 12:44:54PM +0200, Michal Suchanek wrote:
> On 30 May 2016 at 17:50, Mark Brown <broonie@...nel.org> wrote:
> > On Mon, May 30, 2016 at 05:28:10PM +0200, Michal Suchanek wrote:

> >> It's what the driver did to start with and it was requested to fall
> >> back to non-DMA in the case DMA is not available.

> > Why?  I really can't see any sensible use case for this that doesn't
> > have a better solution available.

> Of course, the solution is to compile in the DMA driver.

> It's been argued that some drivers which use only short transfers will
> just work.

With nothing else in the system that needs DMA?  It's making the
performance of the system less reliable for the benefit of a very narrow
use case.

Download attachment "signature.asc" of type "application/pgp-signature" (474 bytes)

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ