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Date: Thu, 17 Jan 2013 21:56:30 +0000
From: Christoph Lameter <cl@linux.com>
Subject: Re: [RFC][PATCH] slub: Check for page NULL before doing the node_match
 check
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To: Steven Rostedt <rostedt@goodmis.org>
Cc: LKML <linux-kernel@vger.kernel.org>, linux-mm <linux-mm@kvack.org>, Andrew Morton <akpm@linux-foundation.org>, Pekka Enberg <penberg@kernel.org>, Matt Mackall <mpm@selenic.com>, Thomas Gleixner <tglx@linutronix.de>, RT <linux-rt-users@vger.kernel.org>, Clark Williams <clark@redhat.com>, John Kacur <jkacur@gmail.com>, "Luis Claudio R. Goncalves" <lgoncalv@redhat.com>

on Thu, 17 Jan 2013, Christoph Lameter wrote:

> Ditto which leaves us with:
>
> Index: linux/mm/slub.c
> ===================================================================
> --- linux.orig/mm/slub.c	2013-01-17 15:49:57.417491975 -0600
> +++ linux/mm/slub.c	2013-01-17 15:50:49.010287150 -0600
> @@ -1993,8 +1993,9 @@ static inline void flush_slab(struct kme
>  	deactivate_slab(s, c->page, c->freelist);
>
>  	c->tid = next_tid(c->tid);
> -	c->page = NULL;
>  	c->freelist = NULL;
> +	barrier();
> +	c->page = NULL;
>  }

But the larger question is why is flush_slab() called with interrupts
enabled?

RT?

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