linux-kernel - Re: lockdep warning with LTP dio test (v2.6.24-rc6-125-g5356f66)

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] [day] [month] [year] [list]

Date:	Fri, 25 Jan 2008 11:16:13 -0500
From:	Chris Mason <chris.mason@...cle.com>
To:	Jan Kara <jack@...e.cz>
Cc:	Zach Brown <zach.brown@...cle.com>, Erez Zadok <ezk@...sunysb.edu>,
	linux-kernel@...r.kernel.org, ext3-users@...hat.com,
	Peter Zijlstra <peterz@...radead.org>,
	linux-fsdevel@...r.kernel.org
Subject: Re: lockdep warning with LTP dio test (v2.6.24-rc6-125-g5356f66)

On Friday 25 January 2008, Jan Kara wrote:

> > If ext3's DIO code only touches transactions in get_block, then it can
> > violate data=ordered rules.  Basically the transaction that allocates
> > the blocks might commit before the DIO code gets around to writing them.
> >
> > A crash in the wrong place will expose stale data on disk.
>
>   Hmm, I've looked at it and I don't think so - look at the rationale in
> the patch below... That patch should fix the lock-inversion problem (at
> least I see no lockdep warnings on my test machine).
>

Ah ok, when I was looking at this I was allowing holes to get filled without 
falling back to buffered.  But, with the orphan inode entry protecting things 
I see how you're safe with this patch.

-chris
--
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/