diff --git a/block/io.c b/block/io.c
index a7bc8bd..0ec9c75 100644
--- a/block/io.c
+++ b/block/io.c
@@ -1819,10 +1819,13 @@ static int64_t coroutine_fn bdrv_co_get_block_status(BlockDriverState *bs,
             /* Ignore errors.  This is just providing extra information, it
              * is useful but not necessary.
              */
-            if (!file_pnum) {
-                /* !file_pnum indicates an offset at or beyond the EOF; it is
-                 * perfectly valid for the format block driver to point to such
-                 * offsets, so catch it and mark everything as zero */
+            if (ret2 & BDRV_BLOCK_EOF &&
+                (!file_pnum || ret2 & BDRV_BLOCK_ZERO)) {
+                /*
+                 * It is valid for the format block driver to read
+                 * beyond the end of the underlying file's current
+                 * size; such areas read as zero.
+                 */
                 ret |= BDRV_BLOCK_ZERO;
             } else {
                 /* Limit request to the range reported by the protocol driver */
@@ -1849,16 +1852,30 @@ static int64_t coroutine_fn bdrv_co_get_block_status_above(BlockDriverState *bs,
 {
     BlockDriverState *p;
     int64_t ret = 0;
+    bool first = true;

     assert(bs != base);
     for (p = bs; p != base; p = backing_bs(p)) {
         ret = bdrv_co_get_block_status(p, sector_num, nb_sectors, pnum, file);
-        if (ret < 0 || ret & BDRV_BLOCK_ALLOCATED) {
+        if (ret < 0) {
+            break;
+        }
+        if (ret & BDRV_BLOCK_ZERO && ret & BDRV_BLOCK_EOF && !first) {
+            /*
+             * Reading beyond the end of the file continues to read
+             * zeroes, but we can only widen the result to the
+             * unallocated length we learned from an earlier
+             * iteration.
+             */
+            *pnum = nb_sectors;
+        }
+        if (ret & (BDRV_BLOCK_ZERO | BDRV_BLOCK_DATA)) {
             break;
         }
         /* [sector_num, pnum] unallocated on this layer, which could be only
          * the first part of [sector_num, nb_sectors].  */
         nb_sectors = MIN(nb_sectors, *pnum);
+        first = false;
     }
     return ret;
 }
diff --git a/tests/qemu-iotests/154 b/tests/qemu-iotests/154
index 687b8f3..d4dae83 100755
--- a/tests/qemu-iotests/154
+++ b/tests/qemu-iotests/154
@@ -334,8 +334,6 @@ $QEMU_IO -c "alloc $size 2048" "$TEST_IMG" | _filter_qemu_io
 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map

 # Repeat with backing file holding unallocated cluster.
-# TODO: Note that this forces an allocation, because we aren't yet able to
-# quickly detect that reads beyond EOF of the backing file are always zero
 CLUSTER_SIZE=2048 TEST_IMG="$TEST_IMG.base" _make_test_img $((size + 1024))

 # Write at the front: sector-wise, the request is:
@@ -371,8 +369,6 @@ $QEMU_IO -c "alloc $size 2048" "$TEST_IMG" | _filter_qemu_io
 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map

 # Repeat with backing file holding zero'd cluster
-# TODO: Note that this forces an allocation, because we aren't yet able to
-# quickly detect that reads beyond EOF of the backing file are always zero
 $QEMU_IO -c "write -z $size 512" "$TEST_IMG.base" | _filter_qemu_io

 # Write at the front: sector-wise, the request is:
diff --git a/tests/qemu-iotests/154.out b/tests/qemu-iotests/154.out
index b86f074..9e7abf2 100644
--- a/tests/qemu-iotests/154.out
+++ b/tests/qemu-iotests/154.out
@@ -310,19 +310,19 @@ wrote 512/512 bytes at offset 134217728
 512 bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
 2048/2048 bytes allocated at offset 128 MiB
 [{ "start": 0, "length": 134217728, "depth": 1, "zero": true, "data": false},
-{ "start": 134217728, "length": 2048, "depth": 0, "zero": false, "data": true, "offset": OFFSET}]
+{ "start": 134217728, "length": 2048, "depth": 0, "zero": true, "data": false}]
 Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=134219776 backing_file=TEST_DIR/t.IMGFMT.base
 wrote 512/512 bytes at offset 134219264
 512 bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
 2048/2048 bytes allocated at offset 128 MiB
 [{ "start": 0, "length": 134217728, "depth": 1, "zero": true, "data": false},
-{ "start": 134217728, "length": 2048, "depth": 0, "zero": false, "data": true, "offset": OFFSET}]
+{ "start": 134217728, "length": 2048, "depth": 0, "zero": true, "data": false}]
 Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=134219776 backing_file=TEST_DIR/t.IMGFMT.base
 wrote 1024/1024 bytes at offset 134218240
 1 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
 2048/2048 bytes allocated at offset 128 MiB
 [{ "start": 0, "length": 134217728, "depth": 1, "zero": true, "data": false},
-{ "start": 134217728, "length": 2048, "depth": 0, "zero": false, "data": true, "offset": OFFSET}]
+{ "start": 134217728, "length": 2048, "depth": 0, "zero": true, "data": false}]
 Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=134219776 backing_file=TEST_DIR/t.IMGFMT.base
 wrote 2048/2048 bytes at offset 134217728
 2 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
@@ -336,19 +336,19 @@ wrote 512/512 bytes at offset 134217728
 512 bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
 2048/2048 bytes allocated at offset 128 MiB
 [{ "start": 0, "length": 134217728, "depth": 1, "zero": true, "data": false},
-{ "start": 134217728, "length": 2048, "depth": 0, "zero": false, "data": true, "offset": OFFSET}]
+{ "start": 134217728, "length": 2048, "depth": 0, "zero": true, "data": false}]
 Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=134219776 backing_file=TEST_DIR/t.IMGFMT.base
 wrote 512/512 bytes at offset 134219264
 512 bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
 2048/2048 bytes allocated at offset 128 MiB
 [{ "start": 0, "length": 134217728, "depth": 1, "zero": true, "data": false},
-{ "start": 134217728, "length": 2048, "depth": 0, "zero": false, "data": true, "offset": OFFSET}]
+{ "start": 134217728, "length": 2048, "depth": 0, "zero": true, "data": false}]
 Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=134219776 backing_file=TEST_DIR/t.IMGFMT.base
 wrote 1024/1024 bytes at offset 134218240
 1 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
 2048/2048 bytes allocated at offset 128 MiB
 [{ "start": 0, "length": 134217728, "depth": 1, "zero": true, "data": false},
-{ "start": 134217728, "length": 2048, "depth": 0, "zero": false, "data": true, "offset": OFFSET}]
+{ "start": 134217728, "length": 2048, "depth": 0, "zero": true, "data": false}]
 Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=134219776 backing_file=TEST_DIR/t.IMGFMT.base
 wrote 2048/2048 bytes at offset 134217728
 2 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
