On Thu, Oct 26, 2017 at 09:59:47AM +0200, Max Reitz wrote:
> qemu-img commit invalidates all images between base and top. This
> should be mentioned in the man page.
>
> Suggested-by: Ping Li <pi...@redhat.com>
> Signed-off-by: Max Reitz <mre...@redhat.com>
> ---
> qemu-img.texi | 9 ++++-----
> 1 file changed, 4 insertions(+), 5 deletions(-)
>
> diff --git a/qemu-img.texi b/qemu-img.texi
> index ee5c5940d3..fdcf120f36 100644
> --- a/qemu-img.texi
> +++ b/qemu-img.texi
> @@ -274,11 +274,10 @@ If the backing chain of the given image file
> @var{filename} has more than one
> layer, the backing file into which the changes will be committed may be
> specified as @var{base} (which has to be part of @var{filename}'s backing
> chain). If @var{base} is not specified, the immediate backing file of the top
> -image (which is @var{filename}) will be used. For reasons of consistency,
> -explicitly specifying @var{base} will always imply @code{-d} (since emptying
> an
> -image after committing to an indirect backing file would lead to different
> data
> -being read from the image due to content in the intermediate backing chain
> -overruling the commit target).
> +image (which is @var{filename}) will be used. Note that after a commit
> operation
> +all images between @var{base} and the top image will be invalid and may
> return
> +garbage data when read. For this reason, @code{-b} implies @code{-d} (so that
> +the top image stays valid).
>
> @item compare [-f @var{fmt}] [-F @var{fmt}] [-T @var{src_cache}] [-p] [-s]
> [-q] @var{filename1} @var{filename2}
>
> --
> 2.13.6
>
>
Reviewed-by: Jeff Cody <jc...@redhat.com>
