linux-kernel - Re: UBI fastmap updates

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:	Sat, 30 Jun 2012 13:43:18 +0300
From:	Artem Bityutskiy <dedekind1@...il.com>
To:	Richard Weinberger <richard@....at>
Cc:	linux-mtd@...ts.infradead.org, nyoushchenko@...sta.com,
	artem.bityutskiy@...ux.intel.com, linux-kernel@...r.kernel.org,
	adrian.hunter@...el.com, Heinz.Egger@...utronix.de,
	thomas.wucher@...utronix.de, shmulik.ladkani@...il.com,
	tglx@...utronix.de, Marius.Mazarel@...l.ro, tim.bird@...sony.com
Subject: Re: UBI fastmap updates

On Fri, 2012-06-29 at 17:14 +0200, Richard Weinberger wrote:
> This is the next round of UBI fastmap updates.
> 
> Fastmap is now disabled by default.
> If you attach an image it will not automatically convert it
> to the fastmap format.
> UBI has a new module parameter "fm_auto".
> If set to 1 UBI will create a fastmap automatically on your
> flash device.
> Please see commit "Add a module parameter to enable fastmap"
> for more details.

One thing I've noticed is that you use vmalloc for some of the buffers
you do I/O on (fm_raw). This is a problem for many ARM platforms because
they cannot do DMA on such buffers. The drivers have to implement
various workarouns for this: either fall back to memcopies or do an
extra copy to a DMA-able buffers.

UBI and UBIFS already to I/O on vmalloc'ed buffers, an I am planning to
fix this, which is not easy. Would be great to not add more of these.

-- 
Best Regards,
Artem Bityutskiy

Download attachment "signature.asc" of type "application/pgp-signature" (837 bytes)