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Date: Wed, 24 Mar 2010 14:49:33 -0500 (CDT)
From: Christoph Lameter <cl@linux-foundation.org>
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To: Eric Dumazet <eric.dumazet@gmail.com>
cc: Pekka J Enberg <penberg@cs.helsinki.fi>,
       linux-kernel <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] slub: Potential stack overflow
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On Wed, 24 Mar 2010, Eric Dumazet wrote:

> Are we allowed to nest in these two functions ?

This is kmem_cache_close() no danger of nesting.

> These are debugging functions, what happens if kmalloc() returns NULL ?

Then you return ENOMEM and the user gets an error. We already do that in
validate_slab_cache().

Hmmm... In this case we called from list_slab_objects() which gets called
from free_partial() (which took a spinlock!) which gets called from
kmem_cache_close().

Its just a debugging aid so no problem if it fails. GFP_ATOMIC?