Re: SLUB/debugobjects locking (Re: 2.6.27-rc4-git1: Reported regressions from 2.6.26)

["Vegard Nossum" <vegard.nossum@gmail.com>]

On Wed, Aug 27, 2008 at 12:14 AM, Daniel J Blueman
<daniel.blueman@gmail.com> wrote:
> On Mon, Aug 25, 2008 at 8:44 PM, Vegard Nossum <vegard.nossum@gmail.com> wrote:
>> I tried your suggestion of promoting the lock to irq-safe, and it
>> fixed the warning for me (didn't get or look for deadlocks yet, but it
>> seems likely that it is caused by the same thing?), the patch is
>> attached for reference.
>>
>> I also don't know if this is the best fix, but I also don't have any
>> other (better) suggestions.
>>
>> Others are welcome to pick it up from here...
>
> The solution looks like is needs to get the lock ordering correct
> w.r.t. SLUB, as we get this, alas:
>
> =======================================================
> [ INFO: possible circular locking dependency detected ]
> 2.6.27-rc4-229c-debug #1

Hm. Is this with my first patch + the one in the e-mail you replied
to? It was intended to be a delta patch on top of my first one.

That would be the one in

    http://marc.info/?l=linux-kernel&m=121946972307110&w=4

plus the one in

    http://marc.info/?l=linux-kernel&m=121969394110327&w=1

Thanks for testing and sorry for the confusion. (Maybe I just confused
myself. Please let me know either way.)


Vegard

-- 
"The animistic metaphor of the bug that maliciously sneaked in while
the programmer was not looking is intellectually dishonest as it
disguises that the error is the programmer's own creation."
	-- E. W. Dijkstra, EWD1036