diff --git a/block/copy-on-read.c b/block/copy-on-read.c
index cc0f848b0f108f0b2ca7a419bd7238bf9577b220..b4d6b7efc30f3e422eb190ace878c3871895bc87 100644
--- a/block/copy-on-read.c
+++ b/block/copy-on-read.c
@@ -259,7 +259,6 @@ static BlockDriver bdrv_copy_on_read = {
     .bdrv_co_eject                      = cor_co_eject,
     .bdrv_co_lock_medium                = cor_co_lock_medium,
 
-    .has_variable_length                = true,
     .is_filter                          = true,
 };
 
diff --git a/block/filter-compress.c b/block/filter-compress.c
index ac285f4b665776f195f6c7213a53f88bcccfce55..320d9576fa1cac2b2d0e445ec593fac90bdf5b9b 100644
--- a/block/filter-compress.c
+++ b/block/filter-compress.c
@@ -146,7 +146,6 @@ static BlockDriver bdrv_compress = {
     .bdrv_co_eject                      = compress_co_eject,
     .bdrv_co_lock_medium                = compress_co_lock_medium,
 
-    .has_variable_length                = true,
     .is_filter                          = true,
 };
 
diff --git a/block/preallocate.c b/block/preallocate.c
index 71c360180945b57f44cd8392d61daee570098a7a..4d821250366ed33299fc99a4e1e75f749e53fd87 100644
--- a/block/preallocate.c
+++ b/block/preallocate.c
@@ -558,7 +558,6 @@ BlockDriver bdrv_preallocate_filter = {
     .bdrv_set_perm = preallocate_set_perm,
     .bdrv_child_perm = preallocate_child_perm,
 
-    .has_variable_length = true,
     .is_filter = true,
 };
 
diff --git a/block/replication.c b/block/replication.c
index de01f9618467158130d6db712e1cbff3f49b0d3a..ea4bf1aa8012bb6a4f38b1d1dd82af67afcd434c 100644
--- a/block/replication.c
+++ b/block/replication.c
@@ -762,7 +762,6 @@ static BlockDriver bdrv_replication = {
 
     .is_filter                  = true,
 
-    .has_variable_length        = true,
     .strong_runtime_opts        = replication_strong_runtime_opts,
 };