diff --git a/eessi/testsuite/hooks.py b/eessi/testsuite/hooks.py
index 1c261077..d15ed76c 100644
--- a/eessi/testsuite/hooks.py
+++ b/eessi/testsuite/hooks.py
@@ -349,11 +349,15 @@ def filter_valid_systems_by_device_type(test: rfm.RegressionTest, required_devic
         # GPU_VENDOR=GPU_VENDORS[NVIDIA] extras
         valid_systems = f'+{FEATURES[GPU]} %{GPU_VENDOR}={GPU_VENDORS[NVIDIA]}'
 
-    elif required_device_type == DEVICE_TYPES[CPU]:
+    elif not is_cuda_module and required_device_type == DEVICE_TYPES[CPU]:
         # Using the CPU requires partitions with FEATURES[CPU] feature
         # Note: making FEATURES[CPU] an explicit feature allows e.g. skipping CPU-based tests on GPU partitions
         valid_systems = f'+{FEATURES[CPU]}'
 
+    elif is_cuda_module and required_device_type == DEVICE_TYPES[CPU]:
+        # Note: This applies for CUDA module tests that want to test only on cpus on gpu partitions.
+        valid_systems = f'+{FEATURES[CPU]} +{FEATURES[GPU]} %{GPU_VENDOR}={GPU_VENDORS[NVIDIA]}'
+
     elif not is_cuda_module and required_device_type == DEVICE_TYPES[GPU]:
         # Invalid combination: a module without GPU support cannot use a GPU
         valid_systems = ''
diff --git a/eessi/testsuite/tests/apps/osu.py b/eessi/testsuite/tests/apps/osu.py
index dde67afe..1a2b3d0a 100644
--- a/eessi/testsuite/tests/apps/osu.py
+++ b/eessi/testsuite/tests/apps/osu.py
@@ -50,13 +50,13 @@ class EESSI_OSU_Micro_Benchmarks_pt2pt(osu_benchmark):
     device_type = parameter([DEVICE_TYPES[CPU], DEVICE_TYPES[GPU]])
     # unset num_tasks_per_node from the hpctestlib.
     num_tasks_per_node = None
-    # Note: device_buffers variable is inherited from the hpctestlib class and adds options to the launcher
-    # commands based on what device is set.
-    device_buffers = 'cpu'
 
     @run_after('init')
     def run_after_init(self):
         """hooks to run after init phase"""
+        # Note: device_buffers variable is inherited from the hpctestlib class and adds options to the launcher
+        # commands (before setup) if not equal to 'cpu'. We set it to 'cpu' initially and change it later in this hook depending on the test.
+        self.device_buffers = 'cpu'
         # Filter on which scales are supported by the partitions defined in the ReFrame configuration
         hooks.filter_supported_scales(self)
 
@@ -113,14 +113,6 @@ def set_num_tasks(self):
         """ Setting scales as tags. """
         hooks.set_tag_scale(self)
 
-    @run_after('setup')
-    def set_environment(self):
-        """ Setting environment variable for CUDA module tests that run on pure cpu nodes."""
-        is_cuda_module = utils.is_cuda_required_module(self.module_name)
-        if (is_cuda_module and self.device_type == DEVICE_TYPES[CPU] and
-                (not FEATURES[GPU] in self.current_partition.features)):
-            self.env_vars = {'LD_LIBRARY_PATH': '$EBROOTCUDA/stubs/lib64:$LD_LIBRARY_PATH'}
-
     @run_after('setup')
     def set_num_tasks_per_node(self):
         """ Setting number of tasks per node and cpus per task in this function. This function sets num_cpus_per_task
@@ -174,6 +166,9 @@ class EESSI_OSU_Micro_Benchmarks_coll(osu_benchmark):
     @run_after('init')
     def run_after_init(self):
         """hooks to run after init phase"""
+        # Note: device_buffers variable is inherited from the hpctestlib class and adds options to the launcher
+        # commands based on what device is set.
+        self.device_buffers = 'cpu'
         hooks.filter_valid_systems_by_device_type( self, required_device_type=self.device_type)
         is_cuda_module = utils.is_cuda_required_module(self.module_name)
         if is_cuda_module and self.device_type == DEVICE_TYPES[GPU]:
@@ -213,14 +208,6 @@ def set_mem(self):
     def set_num_tasks(self):
         hooks.set_tag_scale(self)
 
-    @run_after('setup')
-    def set_environment(self):
-        """ Setting environment variable for CUDA module tests that run on pure cpu nodes."""
-        is_cuda_module = utils.is_cuda_required_module(self.module_name)
-        if (is_cuda_module and self.device_type == DEVICE_TYPES[CPU] and
-                (not FEATURES[GPU] in self.current_partition.features)):
-            self.env_vars = {'LD_LIBRARY_PATH': '$EBROOTCUDA/stubs/lib64:$LD_LIBRARY_PATH'}
-
     @run_after('setup')
     def set_num_tasks_per_node(self):
         """ Setting number of tasks per node, cpus per task and gpus per node in this function. This function sets