linux-kernel - Re: [PATCH 1/2 V2] memory-hotplug: fix BUG_ON in move

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

Message-ID: <55345756.40902@huawei.com>
Date:	Mon, 20 Apr 2015 09:33:10 +0800
From:	Xishi Qiu <qiuxishi@...wei.com>
To:	Yasuaki Ishimatsu <yasu.isimatu@...il.com>
CC:	Andrew Morton <akpm@...ux-foundation.org>,
	Yasuaki Ishimatsu <isimatu.yasuaki@...fujitsu.com>,
	Kamezawa Hiroyuki <kamezawa.hiroyu@...fujitsu.com>,
	<izumi.taku@...fujitsu.com>, Tang Chen <tangchen@...fujitsu.com>,
	Gu Zheng <guz.fnst@...fujitsu.com>,
	Xiexiuqi <xiexiuqi@...wei.com>, Mel Gorman <mgorman@...e.de>,
	David Rientjes <rientjes@...gle.com>,
	Linux MM <linux-mm@...ck.org>,
	LKML <linux-kernel@...r.kernel.org>, <yasu.ishimatsu@...il.com>
Subject: Re: [PATCH 1/2 V2] memory-hotplug: fix BUG_ON in move_freepages()

On 2015/4/18 4:05, Yasuaki Ishimatsu wrote:

> 
> Your patches will fix your issue.
> But, if BIOS reports memory first at node hot add, pgdat can
> not be initialized.
> 
> Memory hot add flows are as follows:
> 
> add_memory
>   ...
>   -> hotadd_new_pgdat()
>   ...
>   -> node_set_online(nid)
> 
> When calling hotadd_new_pgdat() for a hot added node, the node is
> offline because node_set_online() is not called yet. So if applying
> your patches, the pgdat is not initialized in this case.
> 
> Thanks,
> Yasuaki Ishimatsu
> 

Hi Yasuaki,

I'm not quite understand, when BIOS reports memory first, why pgdat
can not be initialized?
When hotadd a new node, hotadd_new_pgdat() will be called too, and
when hotadd memory to a existent node, it's no need to call hotadd_new_pgdat(),
right?

Thanks,
Xishi Qiu

--
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/