linux-kernel - Re: [git patches] xfs and block fixes for virtually indexed arches

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:	Thu, 17 Dec 2009 12:39:57 -0500
From:	tytso@....edu
To:	Linus Torvalds <torvalds@...ux-foundation.org>
Cc:	Kyle McMartin <kyle@...artin.ca>, linux-parisc@...r.kernel.org,
	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
	James.Bottomley@...e.de, hch@...radead.org,
	linux-arch@...r.kernel.org, Jens Axboe <jens.axboe@...cle.com>
Subject: Re: [git patches] xfs and block fixes for virtually indexed arches

On Thu, Dec 17, 2009 at 08:46:33AM -0800, Linus Torvalds wrote:
> kmalloc() memory should be ok. It's backed by "real pages". Doing the DMA 
> translations for such pages is trivial and fundamental.

Sure, but there's some rumors/oral traditions going around that some
block devices want bio address which are page aligned, because they
want to play some kind of refcounting game, and if you pass them a
kmalloc() memory, they will explode in some interesting and
entertaining way.  And it's Weird Shit(tm) (aka iSCSI, AoE) type
drivers, that most of us don't have access to, so just because it
works Just Fine on SATA doesn't mean anything.

And none of this is documented anywhere, which is frustrating as hell.
Just rumors that "if you do this, AoE/iSCSI will corrupt your file
systems".

    	    	    	       		       - Ted
--
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/