Re: [Qemu-devel] [PATCH v2] block: Introduce bs->zero_beyond_eof

[Stefan Hajnoczi <stefanha@gmail.com>]

On Thu, Aug 22, 2013 at 03:24:14PM +0800, Asias He wrote:
> In 4146b46c42e0989cb5842e04d88ab6ccb1713a48 (block: Produce zeros when
> protocols reading beyond end of file), we break qemu-iotests ./check
> -qcow2 022. This happens because qcow2 temporarily sets ->growable = 1
> for vmstate accesses (which are stored beyond the end of regular image
> data).
> 
> We introduce the bs->zero_beyond_eof to allow qcow2_load_vmstate() to
> disable ->zero_beyond_eof temporarily in addition to enable ->growable.
> 
> Suggested-by: Stefan Hajnoczi <stefanha@redhat.com>
> Signed-off-by: Asias He <asias@redhat.com>
> ---
> Changes in v2: Set bs->zero_beyond_eof in bdrv_open_common
> 
>  block.c                   | 4 +++-
>  block/qcow2.c             | 3 +++
>  include/block/block_int.h | 3 +++
>  3 files changed, 9 insertions(+), 1 deletion(-)

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

...with a little twist: since the broken patch hasn't been merged yet
I'm applying this fix *first* to keep the tree bisectable.

Stefan