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Subject: Re: [PATCH kernel 1/2] mm: add the related functions to build the
 free page bitmap
From: Rik van Riel <riel@redhat.com>
To: Liang Li <liang.z.li@intel.com>, mst@redhat.com, viro@zeniv.linux.org.uk,
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Date: Tue, 19 Apr 2016 10:54:19 -0400
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On Tue, 2016-04-19 at 22:34 +0800, Liang Li wrote:
> The free page bitmap will be sent to QEMU through virtio interface
> and used for live migration optimization.
> Drop the cache before building the free page bitmap can get more
> free pages. Whether dropping the cache is decided by user.
> 

How do you prevent the guest from using those
recently-freed pages for something else, between
when you build the bitmap and the live migration
completes?

From mboxrd@z Thu Jan  1 00:00:00 1970
From: Rik van Riel <riel@redhat.com>
Subject: Re: [PATCH kernel 1/2] mm: add the related functions to build the
 free page bitmap
Date: Tue, 19 Apr 2016 10:54:19 -0400
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On Tue, 2016-04-19 at 22:34 +0800, Liang Li wrote:
> The free page bitmap will be sent to QEMU through virtio interface
> and used for live migration optimization.
> Drop the cache before building the free page bitmap can get more
> free pages. Whether dropping the cache is decided by user.
> 

How do you prevent the guest from using those
recently-freed pages for something else, between
when you build the bitmap and the live migration
completes?

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Subject: Re: [Qemu-devel] [PATCH kernel 1/2] mm: add the related functions
 to build the free page bitmap
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To: Liang Li <liang.z.li@intel.com>, mst@redhat.com, viro@zeniv.linux.org.uk, linux-kernel@vger.kernel.org, quintela@redhat.com, amit.shah@redhat.com, pbonzini@redhat.com, dgilbert@redhat.com
Cc: linux-mm@kvack.org, kvm@vger.kernel.org, qemu-devel@nongnu.org, agraf@suse.de, borntraeger@de.ibm.com

On Tue, 2016-04-19 at 22:34 +0800, Liang Li wrote:
> The free page bitmap will be sent to QEMU through virtio interface
> and used for live migration optimization.
> Drop the cache before building the free page bitmap can get more
> free pages. Whether dropping the cache is decided by user.
> 

How do you prevent the guest from using those
recently-freed pages for something else, between
when you build the bitmap and the live migration
completes?