linux-kernel - Re: [PATCH 2/2 V2] slub, hotplug: ignore unrelated node's hot-adding and hot-removing

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date:	Wed, 31 Oct 2012 09:09:58 +0200
From:	Pekka Enberg <penberg@...nel.org>
To:	Lai Jiangshan <laijs@...fujitsu.com>
Cc:	linux-kernel@...r.kernel.org, David Rientjes <rientjes@...gle.com>,
	Minchan Kim <minchan.kim@...il.com>,
	KOSAKI Motohiro <kosaki.motohiro@...fujitsu.com>,
	Yasuaki Ishimatsu <isimatu.yasuaki@...fujitsu.com>,
	Rob Landley <rob@...dley.net>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Jiang Liu <jiang.liu@...wei.com>,
	Kay Sievers <kay.sievers@...y.org>,
	Greg Kroah-Hartman <gregkh@...e.de>,
	Mel Gorman <mgorman@...e.de>,
	FNST-Wen Congyang <wency@...fujitsu.com>,
	linux-doc@...r.kernel.org, linux-mm@...ck.org,
	Christoph Lameter <cl@...ux-foundation.org>,
	Matt Mackall <mpm@...enic.com>
Subject: Re: [PATCH 2/2 V2] slub, hotplug: ignore unrelated node's hot-adding
 and hot-removing

On Wed, Oct 24, 2012 at 12:43 PM, Lai Jiangshan <laijs@...fujitsu.com> wrote:
> SLUB only fucus on the nodes which has normal memory, so ignore the other
> node's hot-adding and hot-removing.
>
> Aka: if some memroy of a node(which has no onlined memory) is online,
> but this new memory onlined is not normal memory(HIGH memory example),
> we should not allocate kmem_cache_node for SLUB.
>
> And if the last normal memory is offlined, but the node still has memroy,
> we should remove kmem_cache_node for that node.(current code delay it when
> all of the memory is offlined)
>
> so we only do something when marg->status_change_nid_normal > 0.
> marg->status_change_nid is not suitable here.
>
> The same problem doesn't exsit in SLAB, because SLAB allocates kmem_list3
> for every node even the node don't have normal memory, SLAB tolerates
> kmem_list3 on alien nodes. SLUB only fucus on the nodes which has normal
> memory, it don't tolerates alien kmem_cache_node, the patch makes
> SLUB become self-compatible and avoid WARN and BUG in a rare condition.
>
> CC: David Rientjes <rientjes@...gle.com>
> Cc: Minchan Kim <minchan.kim@...il.com>
> CC: KOSAKI Motohiro <kosaki.motohiro@...fujitsu.com>
> CC: Yasuaki Ishimatsu <isimatu.yasuaki@...fujitsu.com>
> CC: Rob Landley <rob@...dley.net>
> CC: Andrew Morton <akpm@...ux-foundation.org>
> CC: Jiang Liu <jiang.liu@...wei.com>
> CC: Kay Sievers <kay.sievers@...y.org>
> CC: Greg Kroah-Hartman <gregkh@...e.de>
> CC: Mel Gorman <mgorman@...e.de>
> CC: 'FNST-Wen Congyang' <wency@...fujitsu.com>
> CC: linux-doc@...r.kernel.org
> CC: linux-kernel@...r.kernel.org
> CC: linux-mm@...ck.org
> Signed-off-by: Lai Jiangshan <laijs@...fujitsu.com>

The patch looks OK but changelog doesn't say what problem this fixes,
how you found about it, and do we need this in stable.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/