diff --git a/qemu-img.c b/qemu-img.c
index 7f4938a5ef..53bd32bf8f 100644
--- a/qemu-img.c
+++ b/qemu-img.c
@@ -1681,7 +1681,6 @@ typedef struct ImgConvertState {
     BlockBackend *target;
     bool has_zero_init;
     bool compressed;
-    bool unallocated_blocks_are_zero;
     bool target_is_new;
     bool target_has_backing;
     int64_t target_backing_sectors; /* negative if unknown */
@@ -1726,7 +1725,7 @@ static int convert_iteration_sectors(ImgConvertState *s, int64_t sector_num)
 
     if (s->target_backing_sectors >= 0) {
         if (sector_num >= s->target_backing_sectors) {
-            post_backing_zero = s->unallocated_blocks_are_zero;
+            post_backing_zero = true;
         } else if (sector_num + n > s->target_backing_sectors) {
             /* Split requests around target_backing_sectors (because
              * starting from there, zeros are handled differently) */
@@ -2678,7 +2677,6 @@ static int img_convert(int argc, char **argv)
     } else {
         s.compressed = s.compressed || bdi.needs_compressed_writes;
         s.cluster_sectors = bdi.cluster_size / BDRV_SECTOR_SIZE;
-        s.unallocated_blocks_are_zero = bdi.unallocated_blocks_are_zero;
     }
 
     ret = convert_do_copy(&s);