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Date: Mon, 19 Mar 2007 14:16:01 -0700 (PDT)
From: Christoph Lameter <clameter@sgi.com>
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To: Matt Mackall <mpm@selenic.com>
cc: Pekka J Enberg <penberg@cs.helsinki.fi>, akpm@linux-foundation.org,
       ast@domdv.de, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] slab: deal with NULL pointers passed to kmem_cache_free
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On Mon, 19 Mar 2007, Matt Mackall wrote:

> I think this sort of thing should work:
> 
> a = kmalloc(...)
> b = kmem_cache_alloc(..)
> c = allocate_some_id(...)
> if (!a || !b || !c) {
>    free_some_id(c)
>    kmem_cache_free(c)

^^^^ this requires the specification of a kmem_cache structure and the 
object must be allocated by that cache.

>    kfree(a);

Here we dynamically determine the slab cache and do not verify even which 
slab it came from.

So you can always use kfree if you do not care. kmem_cache_free verifies
correctness.