We do add COW child to the node. In future we are going to forbid adding COW child to the node that doesn't support backing. So, fix it here now.
Don't worry about setting bs->backing itself: it further commit we'll update the block-layer to automatically set/unset this field in generic code. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com> --- tests/unit/test-bdrv-drain.c | 1 + 1 file changed, 1 insertion(+) diff --git a/tests/unit/test-bdrv-drain.c b/tests/unit/test-bdrv-drain.c index 2d3c17e566..45edbd867f 100644 --- a/tests/unit/test-bdrv-drain.c +++ b/tests/unit/test-bdrv-drain.c @@ -1944,6 +1944,7 @@ static void coroutine_fn bdrv_replace_test_co_drain_end(BlockDriverState *bs) static BlockDriver bdrv_replace_test = { .format_name = "replace_test", .instance_size = sizeof(BDRVReplaceTestState), + .supports_backing = true, .bdrv_close = bdrv_replace_test_close, .bdrv_co_preadv = bdrv_replace_test_co_preadv, -- 2.31.1