linux-kernel - Re: [PATCH 4/4] ARM: remove consistent dma region and use common vmalloc range for dma allocations

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]

Date:	Fri, 13 Apr 2012 19:38:13 +0100
From:	Russell King - ARM Linux <linux@....linux.org.uk>
To:	Marek Szyprowski <m.szyprowski@...sung.com>
Cc:	linux-arm-kernel@...ts.infradead.org,
	linaro-mm-sig@...ts.linaro.org, linux-mm@...ck.org,
	linux-kernel@...r.kernel.org,
	Kyungmin Park <kyungmin.park@...sung.com>,
	Arnd Bergmann <arnd@...db.de>,
	Chunsang Jeong <chunsang.jeong@...aro.org>,
	Krishna Reddy <vdumpa@...dia.com>,
	Konrad Rzeszutek Wilk <konrad.wilk@...cle.com>,
	Hiroshi Doyu <hdoyu@...dia.com>,
	Subash Patel <subashrp@...il.com>
Subject: Re: [PATCH 4/4] ARM: remove consistent dma region and use common
	vmalloc range for dma allocations

On Fri, Apr 13, 2012 at 04:05:50PM +0200, Marek Szyprowski wrote:
> This patch changes dma-mapping subsystem to use generic vmalloc areas
> for all consistent dma allocations. This increases the total size limit
> of the consistent allocations and removes platform hacks and a lot of
> duplicated code.

NAK.  I don't think you appreciate the contexts from which the dma coherent
code can be called from, and the reason why we pre-allocate the page
tables (so that IRQ-based allocations work.)

The vmalloc region doesn't allow that because page tables are allocated
using GFP_KERNEL not GFP_ATOMIC.

Sorry.
--
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/