From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx138.postini.com [74.125.245.138]) by kanga.kvack.org (Postfix) with SMTP id E913F6B002B for ; Wed, 17 Oct 2012 04:51:00 -0400 (EDT) Received: by mail-oa0-f41.google.com with SMTP id k14so8827045oag.14 for ; Wed, 17 Oct 2012 01:51:00 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <507E4F0C.9040506@cn.fujitsu.com> References: <507656D1.5020703@jp.fujitsu.com> <50765896.4000300@jp.fujitsu.com> <507E4F0C.9040506@cn.fujitsu.com> From: KOSAKI Motohiro Date: Wed, 17 Oct 2012 04:50:40 -0400 Message-ID: Subject: Re: [PATCH 2/2]suppress "Device nodeX does not have a release() function" warning Content-Type: text/plain; charset=ISO-8859-1 Sender: owner-linux-mm@kvack.org List-ID: To: Wen Congyang Cc: Yasuaki Ishimatsu , linux-mm@kvack.org, linux-kernel@vger.kernel.org, rientjes@google.com, liuj97@gmail.com, minchan.kim@gmail.com, akpm@linux-foundation.org On Wed, Oct 17, 2012 at 2:24 AM, Wen Congyang wrote: > At 10/12/2012 06:33 AM, KOSAKI Motohiro Wrote: >> On Thu, Oct 11, 2012 at 1:26 AM, Yasuaki Ishimatsu >> wrote: >>> When calling unregister_node(), the function shows following message at >>> device_release(). >>> >>> "Device 'node2' does not have a release() function, it is broken and must >>> be fixed." >>> >>> The reason is node's device struct does not have a release() function. >>> >>> So the patch registers node_device_release() to the device's release() >>> function for suppressing the warning message. Additionally, the patch adds >>> memset() to initialize a node struct into register_node(). Because the node >>> struct is part of node_devices[] array and it cannot be freed by >>> node_device_release(). So if system reuses the node struct, it has a garbage. >>> >>> CC: David Rientjes >>> CC: Jiang Liu >>> Cc: Minchan Kim >>> CC: Andrew Morton >>> CC: KOSAKI Motohiro >>> Signed-off-by: Yasuaki Ishimatsu >>> Signed-off-by: Wen Congyang >>> --- >>> drivers/base/node.c | 11 +++++++++++ >>> 1 file changed, 11 insertions(+) >>> >>> Index: linux-3.6/drivers/base/node.c >>> =================================================================== >>> --- linux-3.6.orig/drivers/base/node.c 2012-10-11 10:04:02.149758748 +0900 >>> +++ linux-3.6/drivers/base/node.c 2012-10-11 10:20:34.111806931 +0900 >>> @@ -252,6 +252,14 @@ static inline void hugetlb_register_node >>> static inline void hugetlb_unregister_node(struct node *node) {} >>> #endif >>> >>> +static void node_device_release(struct device *dev) >>> +{ >>> +#if defined(CONFIG_MEMORY_HOTPLUG_SPARSE) && defined(CONFIG_HUGETLBFS) >>> + struct node *node_dev = to_node(dev); >>> + >>> + flush_work(&node_dev->node_work); >>> +#endif >>> +} >> >> The patch description don't explain why this flush_work() is needed. > > If the node is onlined after it is offlined, we will clear the memory, > so we should flush_work() before node_dev is set to 0. So then, it is irrelevant from warning supressness. You should make an another patch. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org