Re: [PATCH] mm: Add additional consistency check

From: Matthew Wilcox
Date: Mon Apr 03 2017 - 10:55:41 EST


On Mon, Apr 03, 2017 at 09:03:50AM -0500, Christoph Lameter wrote:
> On Mon, 3 Apr 2017, Michael Ellerman wrote:
>
> > At least in slab.c it seems that would allow you to "free" an object
> > from one kmem_cache onto the array_cache of another kmem_cache, which
> > seems fishy. But maybe there's a check somewhere I'm missing?
>
> kfree can be used to free any object from any slab cache.

Is that a guarantee? There's some wording in the RCU free code that
seems to indicate we can't rely on that being true.