qemu-img commit invalidates all images between base and top. This should be mentioned in the man page.
Suggested-by: Ping Li <[email protected]> Signed-off-by: Max Reitz <[email protected]> --- 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
