1 files changed, 2 insertions, 1 deletions
diff --git a/block/block-backend.c b/block/block-backend.c
index 5c731a1c6c..3e58b95b8a 100644
--- a/block/block-backend.c
+++ b/block/block-backend.c
@@ -1762,8 +1762,9 @@ int coroutine_fn blk_co_pdiscard(BlockBackend *blk, int64_t offset,
 /* To be called between exactly one pair of blk_inc/dec_in_flight() */
 static int coroutine_fn blk_co_do_flush(BlockBackend *blk)
 {
-    blk_wait_while_drained(blk);
     IO_CODE();
+    blk_wait_while_drained(blk);
+    GRAPH_RDLOCK_GUARD();
 
     if (!blk_is_available(blk)) {
         return -ENOMEDIUM;