linux-kernel - Re: [PATCH 10/29] drivers: add DRIVER_HAS_OWN_IOMMU

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 for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Mon, 01 Sep 2014 13:56:42 +0200
From:	Arnd Bergmann <arnd@...db.de>
To:	Marek Szyprowski <m.szyprowski@...sung.com>
Cc:	linux-arm-kernel@...ts.infradead.org,
	Thierry Reding <treding@...dia.com>,
	Rob Herring <robh@...nel.org>,
	"linux-samsung-soc@...r.kernel.org" 
	<linux-samsung-soc@...r.kernel.org>,
	Shaik Ameer Basha <shaik.ameer@...sung.com>,
	Inki Dae <inki.dae@...sung.com>,
	Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
	Joerg Roedel <joro@...tes.org>,
	"Rafael J. Wysocki" <rjw@...ysocki.net>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	Tomasz Figa <tomasz.figa@...il.com>,
	"linaro-mm-sig@...ts.linaro.org" <linaro-mm-sig@...ts.linaro.org>,
	"iommu@...ts.linux-foundation.org" <iommu@...ts.linux-foundation.org>,
	Kukjin Kim <kgene.kim@...sung.com>,
	Laurent Pinchart <laurent.pinchart@...asonboard.com>,
	Sylwester Nawrocki <s.nawrocki@...sung.com>,
	Olof Johansson <olof@...om.net>,
	Kyungmin Park <kyungmin.park@...sung.com>,
	Cho KyongHo <pullip.cho@...sung.com>
Subject: Re: [PATCH 10/29] drivers: add DRIVER_HAS_OWN_IOMMU_MANAGER flag

On Monday 01 September 2014 12:47:08 Marek Szyprowski wrote:
> > Who do you think needs to set this flag, and who needs to read it?
> 
> In the proposed solution Exynos IOMMU driver creates a separate IO 
> address space
> for every client device in a system and binds it to the default 
> dma-mapping space
> for the given device. When drivers are doing its own management of IO 
> address
> space, instead of relying on what is available by default with dma-mapping
> interface, this will require releasing of the previously created default
> structures and resources. So this flag is set by the driver doing its own
> management of io address space. The flags is then checked by Exynos 
> IOMMU driver
> to avoid creating the default dma-mapping address space for devices 
> which driver
> does its own management.

I don't completely understand it yet. I would assume the device
to be added to the default domain at device creation time
(of_platform_populate), way before we know which device driver
is going to be used. How can this prevent the iommu driver
from doing the association with the domain?

	Arnd
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/