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]
Message-ID: <alpine.DEB.1.10.0906111021340.29827@gentwo.org>
Date:	Thu, 11 Jun 2009 10:24:35 -0400 (EDT)
From:	Christoph Lameter <cl@...ux-foundation.org>
To:	Pekka Enberg <penberg@...helsinki.fi>
cc:	linux-kernel@...r.kernel.org, mel@....ul.ie,
	Larry.Finger@...inger.net
Subject: Re: [PATCH 2/2] SLUB: Disable debugging if it increases the minimum
 page order

On Thu, 11 Jun 2009, Pekka Enberg wrote:

> On Thu, 2009-06-11 at 09:43 -0400, Christoph Lameter wrote:
> > We have had that with SLAB. NO! This leads to the situation that some
> > slabs have debug on and some have not. You just do not know which.
>
> I do see your point but surely we don't want to use order 1 allocations
> in the fall-back case for kmalloc-4096? Couldn't we just add a printk
> saying that debug was disabled for the cache? After all, my patch is
> much better than what SLAB does.

If we are enabling global debugging then we are looking for memory
corruption in *all* slab caches. Disabling debugging of some cache behind
the scenes is bad even if this leads to order 1 allocations.

We could refine the way to specify groups of slab caches that should have
debugging on.

> On Thu, 2009-06-11 at 09:43 -0400, Christoph Lameter wrote:
> > Note that CONFIG_SLUB_DEBUG only enables the code to debug a slab. It does
> > not enable debugging for each slab. CONFIG_SLUB_DEBUG_ON does that.
>
> True. Larry, do you have CONFIG_SLUB_DEBUG_ON enabled or are you passing
> SLUB debugging options to the kernel?


--
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

Powered by Openwall GNU/*/Linux Powered by OpenVZ