When creating an image fails because the format doesn't support option "backing_file" or "backing_fmt", bdrv_img_create() first has qemu_opt_set() put a generic error into @local_err, then puts the real error into @errp with error_setg(), and then propagates the former to the latter, which throws away the generic error. A bit complicated, but works.
Not that qemu_opt_set() returns a useful value, we can simply ignore the generic error instead. Signed-off-by: Markus Armbruster <arm...@redhat.com> --- block.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/block.c b/block.c index 93a5fbf60a..2dcf9afd61 100644 --- a/block.c +++ b/block.c @@ -6087,7 +6087,7 @@ void bdrv_img_create(const char *filename, const char *fmt, if (base_filename) { if (!qemu_opt_set(opts, BLOCK_OPT_BACKING_FILE, base_filename, - &local_err)) { + NULL)) { error_setg(errp, "Backing file not supported for file format '%s'", fmt); goto out; @@ -6095,7 +6095,7 @@ void bdrv_img_create(const char *filename, const char *fmt, } if (base_fmt) { - if (!qemu_opt_set(opts, BLOCK_OPT_BACKING_FMT, base_fmt, &local_err)) { + if (!qemu_opt_set(opts, BLOCK_OPT_BACKING_FMT, base_fmt, NULL)) { error_setg(errp, "Backing file format not supported for file " "format '%s'", fmt); goto out; -- 2.26.2