From mboxrd@z Thu Jan  1 00:00:00 1970
From: Alexander Graf <agraf@suse.de>
Subject: Re: [PATCH v2] powernv: kvm: make _PAGE_NUMA take effect
Date: Mon, 07 Apr 2014 10:36:21 +0200
Message-ID: <53426385.2010102@suse.de>
References: <1390292129-15871-1-git-send-email-pingfank@linux.vnet.ibm.com> <8761pdk6x5.fsf@linux.vnet.ibm.com> <C4D7ADEA-9CEB-4717-9AFD-CC8EFB18184A@suse.de> <CAFgQCTs8LSXUi+AwxR9j+2-QRGw4EFZWx-JxktAnJ3VvwLJb9A@mail.gmail.com> <533D47CD.906@suse.com> <87bnwdshzu.fsf@linux.vnet.ibm.com>
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Cc: linuxppc-dev@lists.ozlabs.org, kvm-ppc <kvm-ppc@vger.kernel.org>,
	kvm-devel <kvm@vger.kernel.org>,
	Ben Herrenschmidt <benh@kernel.crashing.org>,
	Paul Mackerras <paulus@samba.org>
To: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>,
	Alexander Graf <agraf@suse.com>,
	Liu ping fan <kernelfans@gmail.com>
Return-path: <kvm-ppc-owner@vger.kernel.org>
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Sender: kvm-ppc-owner@vger.kernel.org
List-Id: kvm.vger.kernel.org


On 07.04.14 09:42, Aneesh Kumar K.V wrote:
> Alexander Graf <agraf@suse.com> writes:
>
>> On 03.04.14 04:36, Liu ping fan wrote:
>>> Hi Alex, could you help to pick up this patch? since  v3.14 kernel can
>>> enable numa fault for powerpc.
>> What bad happens without this patch? We map a page even though it was
>> declared to get NUMA migrated? What happens next?
> Nothing much, we won't be properly accounting the numa access in the
> host.  What we want to achieve is to convert a guest access of the page to
> a host fault so that we can do proper numa access accounting in the
> host. This would enable us to migrate the page to the correct numa
> node.

Ok, so no breakages, just less performance. I wouldn't consider it 
stable material then :).


Alex