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Date: Thu, 21 Mar 2013 07:20:34 +0200
From: "Michael S. Tsirkin" <mst@redhat.com>
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Subject: Re: [Qemu-devel] [RFC PATCH RDMA support v4: 03/10] more verbose
 documentation of the RDMA transport
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To: "Michael R. Hines" <mrhines@linux.vnet.ibm.com>
Cc: aliguori@us.ibm.com, qemu-devel@nongnu.org, owasserm@redhat.com, abali@us.ibm.com, mrhines@us.ibm.com, gokul@us.ibm.com, Paolo Bonzini <pbonzini@redhat.com>

On Wed, Mar 20, 2013 at 04:56:01PM -0400, Michael R. Hines wrote:
> 
> Forgive me, vmsplice system call? Or some other interface?
> 
> I'm not following......
> 
> On 03/20/2013 04:46 PM, Michael S. Tsirkin wrote:
> >On Wed, Mar 20, 2013 at 04:39:00PM -0400, Michael R. Hines wrote:
> >>Unmapped virtual addresses cannot be pinned for RDMA (the hardware
> >>will break),
> >>but there's no way to know they are unmapped without checking
> >>another data structure.
> >So for RDMA, when you try to register them, this will fault them in.

I'm just saying get_user_pages brings pages back in from swap.