Re: [Qemu-devel] [RFC PATCH 00/10] make qed and live migration usage safe

[Stefan Hajnoczi]

On Tue, Mar 06, 2012 at 06:32:19PM +0100, Benoît Canet wrote:
> QED + live migration is an unsafe and disabled mix.
> 
> This patchset make qed and live migration safe to use.
> 
> The check of QED images is delayed during the incoming migration.
> After the migration complete the QED images are checked.
> 
> Benoît Canet (10):
>   block: Add new BDRV_O_INCOMING flag to notice incoming live migration
>   block: add a function to set incoming live migration
>   block: add a function to clear incoming live migration
>   block: rename *_invalidate_cache_* to *_post_incoming_migration_*
>   migration: inform the block layer of incoming live status
>   block: open images with BDRV_O_INCOMING on incoming live migration
>   qed: extract image checking into check_image_if_needed
>   qed: add bdrv_post_incoming_migration operation checking the image
>   qed: honor BDRV_O_INCOMING for incoming live migration
>   qed: remove incoming live migration blocker
> 
>  block.c       |   35 +++++++++++++++++++++---
>  block.h       |   13 +++++++--
>  block/qcow2.c |    7 ++++-
>  block/qed.c   |   81 
> +++++++++++++++++++++++++++++++++++----------------------
>  block/qed.h   |    2 -
>  block_int.h   |    4 +-
>  migration.c   |    9 +++++-
>  vl.c          |    5 +++
>  8 files changed, 110 insertions(+), 46 deletions(-)

We talked about image format live migration approaches on IRC today with
Kevin.  I think the approach you have here will do the job.

Stefan