From mboxrd@z Thu Jan  1 00:00:00 1970
From: Alex Chiang <achiang@hp.com>
Date: Tue, 19 Jan 2010 21:29:35 +0000
Subject: Re: SLUB ia64 linux-next crash bisected to 756dee75
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List-Id: <linux-ia64.vger.kernel.org>
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To: Christoph Lameter <cl@linux-foundation.org>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>, penberg@cs.helsinki.fi, linux-ia64@vger.kernel.org, linux-mm@kvack.org

* Christoph Lameter <cl@linux-foundation.org>:
> On Tue, 19 Jan 2010, Alex Chiang wrote:
> 
> > Well, making progress (maybe?).
> 
> Yes I think this is the fix.
> 
> > Now we're hitting a BUG_ON().
> 
> Thats a kfree of an object not allocated with a slab allocator.
> Recovery is easy in such a case: Dont free the object.

I don't get it.

static int sr_probe(struct device *dev)
{
	/* ... */

	cd = kzalloc(sizeof(*cd), GFP_KERNEL);
	if (!cd)
		goto fail;

	/* ... */

	fail_put:
		put_disk(disk);
	fail_free:
		kfree(cd);
}

The kfree() is balanced with kzalloc(). Unless the stack trace is
lying to us?

/ac