Incompatibilities of kmem_cache_create

Incompatibilities of kmem_cache_create

[werner]

[-- Attachment #1: Type: text/plain, Size: 523 bytes --]

Of the kernel 2.6.22-git15 of this night,  kmem_cache_create is not compatible and causes compiling errors of some fundamental programs.  Before, this error didnt occur.

At least this happened on compiling the externel modules for btrfs and ndiskwrapper.    Principally the compatibility of the Kernel with older and new versions of the file systems have to be observed very good, for the reliability to can read dates.

Thus this should be checked, and corrected

Werner Landgraf

werner@copaya.yi.org

www.copaya.yi.org

Re: Incompatibilities of kmem_cache_create

[Paul Mundt]

On Sat, Jul 21, 2007 at 02:50:01AM -0300, werner wrote:
> Of the kernel 2.6.22-git15 of this night,  kmem_cache_create is not
> compatible and causes compiling errors of some fundamental programs.
> Before, this error didnt occur.
> 
Slab destructors haven't been supported in the kernel for ages, anything
that's relying on them to work out-of-tree is fundamentally broken.

> At least this happened on compiling the externel modules for btrfs and
> ndiskwrapper.    Principally the compatibility of the Kernel with older
> and new versions of the file systems have to be observed very good, for
> the reliability to can read dates.
> 
> Thus this should be checked, and corrected
> 
Indeed it should. You can correct this by removing the extraneous NULL
parameter for the slab dtor from the kmem_cache_create() callsite in the
out-of-tree code. All of the in-tree users were already converted.

Re: Incompatibilities of kmem_cache_create

[Christoph Lameter]

On Sat, 21 Jul 2007, Paul Mundt wrote:

> On Sat, Jul 21, 2007 at 02:50:01AM -0300, werner wrote:
> > Of the kernel 2.6.22-git15 of this night,  kmem_cache_create is not
> > compatible and causes compiling errors of some fundamental programs.
> > Before, this error didnt occur.
> > 
> Slab destructors haven't been supported in the kernel for ages, anything
> that's relying on them to work out-of-tree is fundamentally broken.

Slab destructors were supported and used in Linux kernels up to 
version 2.6.20. They were removed late in the 2.6.21 merge cycle.