diff --git a/block/mirror.c b/block/mirror.c
index d8ecb9efa2..3c4ab1159d 100644
--- a/block/mirror.c
+++ b/block/mirror.c
@@ -73,7 +73,7 @@ typedef struct MirrorBlockJob {
 
     uint64_t last_pause_ns;
     unsigned long *in_flight_bitmap;
-    int in_flight;
+    unsigned in_flight;
     int64_t bytes_in_flight;
     QTAILQ_HEAD(, MirrorOp) ops_in_flight;
     int ret;
diff --git a/block/nbd.c b/block/nbd.c
index 5849d312cc..97683cce27 100644
--- a/block/nbd.c
+++ b/block/nbd.c
@@ -77,7 +77,7 @@ typedef struct BDRVNBDState {
     QemuMutex requests_lock;
     NBDClientState state;
     CoQueue free_sema;
-    int in_flight;
+    unsigned in_flight;
     NBDClientRequest requests[MAX_NBD_REQUESTS];
     QEMUTimer *reconnect_delay_timer;