On 24.04.20 00:17, Eric Blake wrote:
> Our comment did not actually match the code.  Rewrite the comment to
> be less sensitive to any future changes to qcow2-bitmap.c that might
> implement scenarios that we currently reject.
> 
> Signed-off-by: Eric Blake <eblake@redhat.com>
> ---
>  block/qcow2.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/block/qcow2.c b/block/qcow2.c
> index 34888a793354..6b6d1c3fa8b9 100644
> --- a/block/qcow2.c
> +++ b/block/qcow2.c
> @@ -3997,7 +3997,7 @@ static int coroutine_fn qcow2_co_truncate(BlockDriverState *bs, int64_t offset,
>          goto fail;
>      }
> 
> -    /* cannot proceed if image has bitmaps */
> +    /* See qcow2-bitmap.c for which bitmap scenarios prevent a resize. */

Clever. ;)

Reviewed-by: Max Reitz <mreitz@redhat.com>

>      if (qcow2_truncate_bitmaps_check(bs, errp)) {
>          ret = -ENOTSUP;
>          goto fail;
>