linux-kernel - Re: [patch 4/4] x86: allow CONFIG_ISA_DMA

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: <201101270923.37476.arnd@arndb.de>
Date:	Thu, 27 Jan 2011 09:23:37 +0100
From:	Arnd Bergmann <arnd@...db.de>
To:	David Rientjes <rientjes@...gle.com>
Cc:	Andrew Morton <akpm@...ux-foundation.org>,
	Ingo Molnar <mingo@...hat.com>,
	"H. Peter Anvin" <hpa@...or.com>,
	Thomas Gleixner <tglx@...utronix.de>,
	Adam Belay <abelay@....edu>,
	Bjorn Helgaas <bjorn.helgaas@...com>,
	Russell King <linux@....linux.org.uk>, x86@...nel.org,
	linux-kernel@...r.kernel.org
Subject: Re: [patch 4/4] x86: allow CONFIG_ISA_DMA_API to be disabled

On Thursday 27 January 2011 04:14:54 David Rientjes wrote:
> 
> Not all 64-bit systems require ISA-style DMA, so allow it to be
> configurable.  x86 utilizes the generic ISA DMA allocator from
> kernel/dma.c, so require it only when CONFIG_ISA_DMA_API is enabled.
> 
> Disabling CONFIG_ISA_DMA_API is dependent on x86_64 since those machines
> do not have ISA slots and benefit the most from disabling the option (and
> on CONFIG_EXPERT as required by H. Peter Anvin).

But the x86_64 machines can also run 32 bit kernel, and I would expect
that they don't need ISA DMA in that configuration either.

I think it would make sense to let the CONFIG_EXPERT user disable
DMA for 32 bit as well.

	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/