Re: [Qemu-devel] [PATCH v2 for-2.0] blockdev: Refuse to open encrypted image unless paused

[Stefan Hajnoczi <stefanha@redhat.com>]

On Fri, Mar 14, 2014 at 09:22:48AM +0100, Markus Armbruster wrote:
> Opening an encrypted image takes an additional step: setting the key.
> Between open and the key set, the image must not be used.
> 
> We have some protection against accidental use in place: you can't
> unpause a guest while we're missing keys.  You can, however, hot-plug
> block devices lacking keys into a running guest just fine, or insert
> media lacking keys.  In the latter case, notifying the guest of the
> insert is delayed until the key is set, which may suffice to protect
> at least some guests in common usage.
> 
> This patch makes the protection apply in more cases, in a rather
> heavy-handed way: it doesn't let you open encrypted images unless
> we're in a paused state.
> 
> It doesn't extend the protection to users other than the guest (block
> jobs?).  Use of runstate_check() from block.c is disgusting.  Best I
> can do right now.
> 
> Signed-off-by: Markus Armbruster <armbru@redhat.com>
> ---
> v2:
> * Don't break -incoming [Paolo]
> * Update qemu-iotests/087 [Fam]
> 
>  block.c                    |  9 ++++++++-
>  stubs/Makefile.objs        |  1 +
>  stubs/runstate-check.c     |  6 ++++++
>  tests/qemu-iotests/087     | 17 +++++++++++++++++
>  tests/qemu-iotests/087.out | 11 ++++++++++-
>  5 files changed, 42 insertions(+), 2 deletions(-)
>  create mode 100644 stubs/runstate-check.c

Thanks, applied to my block tree:
https://github.com/stefanha/qemu/commits/block

Stefan