linux-kernel - Re: [PATCH v2] ARM: mm: Do not invoke OOM for higher order IOMMU 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:	Mon, 23 Mar 2015 09:30:30 -0700
From:	Doug Anderson <dianders@...omium.org>
To:	Tomasz Figa <tfiga@...omium.org>
Cc:	"linux-arm-kernel@...ts.infradead.org" 
	<linux-arm-kernel@...ts.infradead.org>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	Russell King <linux@....linux.org.uk>,
	Marek Szyprowski <m.szyprowski@...sung.com>,
	Will Deacon <will.deacon@....com>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Laura Abbott <lauraa@...eaurora.org>,
	Ritesh Harjani <ritesh.harjani@...il.com>,
	Carlo Caione <carlo@...one.org>,
	Laurent Pinchart <laurent.pinchart+renesas@...asonboard.com>,
	Sonny Rao <sonnyrao@...omium.org>,
	David Rientjes <rientjes@...gle.com>
Subject: Re: [PATCH v2] ARM: mm: Do not invoke OOM for higher order IOMMU DMA allocations

Tomasz,

On Mon, Mar 23, 2015 at 12:27 AM, Tomasz Figa <tfiga@...omium.org> wrote:
> IOMMU should be able to use single pages as well as bigger blocks, so if
> higher order allocations fail, we should not affect state of the system,
> with events such as OOM killer, but rather fall back to order 0
> allocations.
>
> This patch changes the behavior of ARM IOMMU DMA allocator to use
> __GFP_NORETRY, which bypasses OOM invocation, for orders higher than
> zero and, only if that fails, fall back to normal order 0 allocation
> which might invoke OOM killer.
>
> Signed-off-by: Tomasz Figa <tfiga@...omium.org>
> ---
>  arch/arm/mm/dma-mapping.c | 27 +++++++++++++++++++++------
>  1 file changed, 21 insertions(+), 6 deletions(-)

FWIW:

Reviewed-by: Doug Anderson <dianders@...omium.org>
--
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/