linux-kernel - Re: [2.6.20][PATCH] fix mempolicy error check on a system with memory-less-node

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: <20070207190738.30f1d419.kamezawa.hiroyu@jp.fujitsu.com>
Date:	Wed, 7 Feb 2007 19:07:38 +0900
From:	KAMEZAWA Hiroyuki <kamezawa.hiroyu@...fujitsu.com>
To:	Andi Kleen <ak@...e.de>
Cc:	linux-kernel@...r.kernel.org, y-goto@...fujitsu.com,
	clameter@...r.sgi.com, akpm@...l.org
Subject: Re: [2.6.20][PATCH] fix mempolicy error check on a system with
 memory-less-node

On 07 Feb 2007 11:20:06 +0100
Andi Kleen <ak@...e.de> wrote:

> KAMEZAWA Hiroyuki <kamezawa.hiroyu@...fujitsu.com> writes:
> 
> > current mempolicy just checks whether a node is online or not.
> > If there is memory-less-node, mempolicy's target node can be
> > invalid.
> > This patch adds a check whether a node has memory or not.
> 
> IMHO there shouldn't be any memory less nodes. The architecture code
> should not create them. The CPU should be assigned to a nearby node instead.
> At least x86-64 ensures that.
> 
AFAIK, ia64 creates nodes just depends on SRAT's possible resource information.
Then, ia64 can create cpu-memory-less-node(node with no available resource.).
(*)I don't like this.

If we don't allow memory-less-node, we may have to add several codes for cpu-hot-add.
cpus should be moved to nearby node at hotadd .
And node-hot-add have to care that cpus mustn't be added before memory, cpu-driven 
node-hot-add will never occur. (ACPI's 'container' device spec can't guaranntee this.)

-Kame



-
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/