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, 10 Oct 2008 11:40:56 +0900
From:	FUJITA Tomonori <fujita.tomonori@....ntt.co.jp>
To:	yinghai@...nel.org
Cc:	grundler@...isc-linux.org, matthew@....cx,
	jbarnes@...tuousgeek.org, mingo@...e.hu, tglx@...utronix.de,
	hpa@...or.com, akpm@...ux-foundation.org,
	linux-kernel@...r.kernel.org, linux-pci@...r.kernel.org
Subject: Re: [PATCH] pci: print out DMA mask info

On Thu, 09 Oct 2008 16:05:57 -0700
Yinghai Lu <yinghai@...nel.org> wrote:

> Grant Grundler wrote:
> > On Thu, Oct 09, 2008 at 02:51:32PM -0700, Yinghai Lu wrote:
> >> On Thu, Oct 9, 2008 at 2:35 PM, Matthew Wilcox <matthew@....cx> wrote:
> >>> Why's that interesting to the sysadmin of the machine?  To the driver
> >>> writer, certainly.  But what's the use of it to the people using the
> >>> machine?
> > ...
> >> make linux kernel act like black box as other os?
> > 
> > I don't understand your reply.
> > If someone thinks linux is a black box, printing this message won't help them.
> > 
> could find out easily why some driver doesn't set dma mask correctly.
> like why 
> 	qlogic qla2xxx only set consistent to 64bit,
> 	emulex lpfc not set consistent to 64bit

IIRC, except for one SGI architecture, coherent_dma_mask is
meaningless, dma_mask is always equal to coherent_dma_mask. Lots of
IOMMU implementations ignore coherent_dma_mask and use dma_mask for
alloc_coherent(). Some drivers doesn't set up coherent_dma_mask.

Theoretically, we need to fix this but it doesn't cause any
problem. That's why nobody cares about it, I guess.
--
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/

Powered by blists - more mailing lists