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Date: Tue, 27 May 2014 09:38:28 -0500 (CDT)
From: Christoph Lameter <cl@gentwo.org>
To: Vladimir Davydov <vdavydov@parallels.com>
cc: hannes@cmpxchg.org, mhocko@suse.cz, akpm@linux-foundation.org,
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Subject: Re: [PATCH RFC 3/3] slub: reparent memcg caches' slabs on memcg
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On Fri, 23 May 2014, Vladimir Davydov wrote:

> > If you look at the end of unfreeze_partials() you see that we release
> > locks and therefore enable preempt before calling into the page allocator.
>
> Yes, we release the node's list_lock before calling discard_slab(), but
> we don't enable irqs, which are disabled in put_cpu_partial(), just
> before calling it, so we call the page allocator with irqs off and
> therefore preemption disabled.

Ok that is something that could be fixed.