diff --git a/block.c b/block.c
index 1271dd2acda7271a4fa8c96525fcfa1e0b94c20c..aa9b5abf5dbccf4318cd75a4ba9c7280bdb3b228 100644
--- a/block.c
+++ b/block.c
@@ -1097,14 +1097,30 @@ fail:
 void bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd)
 {
 
+    if (bs->backing_hd) {
+        assert(bs->backing_blocker);
+        bdrv_op_unblock_all(bs->backing_hd, bs->backing_blocker);
+    } else if (backing_hd) {
+        error_setg(&bs->backing_blocker,
+                   "device is used as backing hd of '%s'",
+                   bs->device_name);
+    }
+
     bs->backing_hd = backing_hd;
     if (!backing_hd) {
+        error_free(bs->backing_blocker);
+        bs->backing_blocker = NULL;
         goto out;
     }
     bs->open_flags &= ~BDRV_O_NO_BACKING;
     pstrcpy(bs->backing_file, sizeof(bs->backing_file), backing_hd->filename);
     pstrcpy(bs->backing_format, sizeof(bs->backing_format),
             backing_hd->drv ? backing_hd->drv->format_name : "");
+
+    bdrv_op_block_all(bs->backing_hd, bs->backing_blocker);
+    /* Otherwise we won't be able to commit due to check in bdrv_commit */
+    bdrv_op_unblock(bs->backing_hd, BLOCK_OP_TYPE_COMMIT,
+                    bs->backing_blocker);
 out:
     bdrv_refresh_limits(bs);
 }
@@ -1803,8 +1819,9 @@ void bdrv_close(BlockDriverState *bs)
 
     if (bs->drv) {
         if (bs->backing_hd) {
-            bdrv_unref(bs->backing_hd);
-            bs->backing_hd = NULL;
+            BlockDriverState *backing_hd = bs->backing_hd;
+            bdrv_set_backing_hd(bs, NULL);
+            bdrv_unref(backing_hd);
         }
         bs->drv->bdrv_close(bs);
         g_free(bs->opaque);
@@ -2006,7 +2023,6 @@ void bdrv_swap(BlockDriverState *bs_new, BlockDriverState *bs_old)
     assert(QLIST_EMPTY(&bs_new->dirty_bitmaps));
     assert(bs_new->job == NULL);
     assert(bs_new->dev == NULL);
-    assert(bdrv_op_blocker_is_empty(bs_new));
     assert(bs_new->io_limits_enabled == false);
     assert(!throttle_have_timer(&bs_new->throttle_state));
 
@@ -2025,7 +2041,6 @@ void bdrv_swap(BlockDriverState *bs_new, BlockDriverState *bs_old)
     /* Check a few fields that should remain attached to the device */
     assert(bs_new->dev == NULL);
     assert(bs_new->job == NULL);
-    assert(bdrv_op_blocker_is_empty(bs_new));
     assert(bs_new->io_limits_enabled == false);
     assert(!throttle_have_timer(&bs_new->throttle_state));
 
diff --git a/block/mirror.c b/block/mirror.c
index 1c38aa8f7700250fb2fa4201d21b96cdac201b16..94c8661777c4b9e50e96ac6d1deb6c91d5bb00a7 100644
--- a/block/mirror.c
+++ b/block/mirror.c
@@ -498,7 +498,7 @@ immediate_exit:
             /* drop the bs loop chain formed by the swap: break the loop then
              * trigger the unref from the top one */
             BlockDriverState *p = s->base->backing_hd;
-            s->base->backing_hd = NULL;
+            bdrv_set_backing_hd(s->base, NULL);
             bdrv_unref(p);
         }
     }
diff --git a/include/block/block_int.h b/include/block/block_int.h
index 7b1c013c30d9725fc1506c5ed24198f63c1f1e91..f2e753f63243d43af91ad4c141b578a76f024559 100644
--- a/include/block/block_int.h
+++ b/include/block/block_int.h
@@ -369,6 +369,9 @@ struct BlockDriverState {
 
     QDict *options;
     BlockdevDetectZeroesOptions detect_zeroes;
+
+    /* The error object in use for blocking operations on backing_hd */
+    Error *backing_blocker;
 };
 
 int get_tmp_filename(char *filename, int size);