diff --git a/loopy/transform/buffer.py b/loopy/transform/buffer.py
index b848a6f98abdc91ea6d9fd8052cae7de035cdfb3..57c4397f998a74222bc482127076dee809de2bac 100644
--- a/loopy/transform/buffer.py
+++ b/loopy/transform/buffer.py
@@ -245,7 +245,7 @@ def buffer_array_for_single_kernel(kernel, program_callables_info, var_name,
 
     from loopy.preprocess import prepare_for_caching
     key_kernel = prepare_for_caching(kernel)
-    cache_key = (key_kernel, program_callables_info, var_name,
+    cache_key = (key_kernel, var_name,
             tuple(buffer_inames),
             PymbolicExpressionHashWrapper(init_expression),
             PymbolicExpressionHashWrapper(store_expression), within,
diff --git a/loopy/transform/iname.py b/loopy/transform/iname.py
index 0d5f2015e293e977ebf29ee06b29bed9f6c20a73..20dc9a99bddf18ffcc7b381275614f24e95f6ed8 100644
--- a/loopy/transform/iname.py
+++ b/loopy/transform/iname.py
@@ -1088,6 +1088,7 @@ def has_schedulable_iname_nesting(knl):
 
 # {{{ rename_inames
 
+@iterate_over_kernels_if_given_program
 def rename_iname(knl, old_iname, new_iname, existing_ok=False, within=None):
     """
     :arg within: a stack match as understood by
diff --git a/loopy/transform/subst.py b/loopy/transform/subst.py
index 0dbc7939e681d45c0b292ed49b1eeb244c97f82e..6a93e0bd99bc779f66fa3fb0aea67b55ea246740 100644
--- a/loopy/transform/subst.py
+++ b/loopy/transform/subst.py
@@ -35,6 +35,7 @@ from pymbolic import var
 
 from loopy.program import iterate_over_kernels_if_given_program
 from loopy.kernel import LoopKernel
+from loopy.kernel.function_interface import CallableKernel, ScalarCallable
 
 import logging
 logger = logging.getLogger(__name__)
@@ -508,8 +509,17 @@ def find_rules_matching(knl, pattern):
     return [r for r in knl.substitutions if pattern.match(r)]
 
 
-def find_one_rule_matching(knl, pattern):
-    rules = find_rules_matching(knl, pattern)
+def find_one_rule_matching(program, pattern):
+    rules = []
+    for in_knl_callable in program.program_callables_info.values():
+        if isinstance(in_knl_callable, CallableKernel):
+            knl = in_knl_callable.subkernel
+            rules.extend(find_rules_matching(knl, pattern))
+        elif isinstance(in_knl_callable, ScalarCallable):
+            pass
+        else:
+            raise NotImplementedError("Unknown callable types %s." % (
+                type(in_knl_callable).__name__))
 
     if len(rules) > 1:
         raise ValueError("more than one substitution rule matched '%s'"
diff --git a/test/test_fortran.py b/test/test_fortran.py
index deca4d42e6ffcfc10292039bb17449ffb141f112..1a5a0c383615e2ca5a59b34fc1aef6300f14d89f 100644
--- a/test/test_fortran.py
+++ b/test/test_fortran.py
@@ -410,7 +410,7 @@ def test_fuse_kernels(ctx_factory):
     knl = lp.fuse_kernels((xderiv, yderiv), data_flow=[("result", 0, 1)])
     knl = lp.prioritize_loops(knl, "e,i,j,k")
 
-    assert len(knl.temporary_variables) == 2
+    assert len(knl.root_kernel.temporary_variables) == 2
 
     ctx = ctx_factory()
     lp.auto_test_vs_ref(xyderiv, ctx, knl, parameters=dict(nelements=20, ndofs=4))
diff --git a/test/test_numa_diff.py b/test/test_numa_diff.py
index 6b578838d99cb5aa28296619fdec6e8a2359ba0b..4f802f8bff3ba00763825bc09dbc6051ff1ac527 100644
--- a/test/test_numa_diff.py
+++ b/test/test_numa_diff.py
@@ -246,7 +246,9 @@ def test_gnuma_horiz_kernel(ctx_factory, ilp_multiple, Nq, opt_level):  # noqa
          "-cl-no-signed-zeros",
          ])
 
-    hsv = hsv.copy(name="horizontalStrongVolumeKernel")
+    # FIXME: renaming's a bit tricky in this program model.
+    # add a simple transformation for it
+    # hsv = hsv.copy(name="horizontalStrongVolumeKernel")
 
     results = lp.auto_test_vs_ref(ref_hsv, ctx, hsv, parameters=dict(elements=300),
             quiet=True)