From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCH] slub: Make CONFIG_PAGE_ALLOC work with new fastpath
Date: Fri, 13 May 2011 23:26:42 +0200
Message-ID: <1305322002.3120.11.camel@edumazet-laptop>
References: <bug-33502-10286@https.bugzilla.kernel.org/>
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	 <1303244270.2756.3.camel@edumazet-laptop> <4DC90D7D.9030808@cs.helsinki.fi>
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Cc: Vegard Nossum <vegardno@ifi.uio.no>,
	Pekka Enberg <penberg@cs.helsinki.fi>,
	casteyde.christian@free.fr,
	Andrew Morton <akpm@linux-foundation.org>,
	netdev@vger.kernel.org, bugzilla-daemon@bugzilla.kernel.org,
	bugme-daemon@bugzilla.kernel.org
To: Christoph Lameter <cl@linux.com>
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Le vendredi 13 mai 2011 =C3=A0 16:15 -0500, Christoph Lameter a =C3=A9c=
rit :
> I ran this with hackbench under KVM with CONFIG_DEBUG_PAGEALLOC and I=
 saw
> no failures.
>=20
>=20
> Subject: slub: Make CONFIG_PAGE_ALLOC work with new fastpath
>=20
> Fastpath can do a speculative access to a page that CONFIG_PAGE_ALLOC=
 may have
> marked as invalid to retrieve the pointer to the next free object.
>=20
> Use probe_kernel_read in that case in order not to cause a page fault=
=2E
>=20
> Signed-off-by: Christoph Lameter <cl@linux.com>

Reported-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>

Thanks !