diff --git a/inc/ocf_err.h b/inc/ocf_err.h
index e3e7dba..e4f71f2 100644
--- a/inc/ocf_err.h
+++ b/inc/ocf_err.h
@@ -102,6 +102,9 @@ typedef enum {
 	/** Flushing of core interrupted */
 	OCF_ERR_FLUSHING_INTERRUPTED,
 
+	/** Another flushing operation in progress */
+	OCF_ERR_FLUSH_IN_PROGRESS,
+
 	/** Adding core to core pool failed */
 	OCF_ERR_CANNOT_ADD_CORE_TO_POOL,
 
diff --git a/src/mngt/ocf_mngt_flush.c b/src/mngt/ocf_mngt_flush.c
index 8e41104..78e63c2 100644
--- a/src/mngt/ocf_mngt_flush.c
+++ b/src/mngt/ocf_mngt_flush.c
@@ -47,6 +47,11 @@ struct ocf_mngt_cache_flush_context
 	/* target core */
 	ocf_core_t core;
 
+	struct {
+		bool lock : 1;
+		bool freeze : 1;
+	} flags;
+
 	/* management operation identifier */
 	enum {
 		flush_cache = 0,
@@ -87,24 +92,22 @@ static void _ocf_mngt_begin_flush(ocf_pipeline_t pipeline, void *priv,
 {
 	struct ocf_mngt_cache_flush_context *context = priv;
 	ocf_cache_t cache = context->cache;
+	int result;
 
 	/* FIXME: need mechanism for async waiting for outstanding flushes to
 	 * finish */
-	env_mutex_lock(&cache->flush_mutex);
+	result = env_mutex_trylock(&cache->flush_mutex);
+	if (result)
+		OCF_PL_FINISH_RET(pipeline, -OCF_ERR_FLUSH_IN_PROGRESS);
+	context->flags.lock = true;
 
 	ocf_refcnt_freeze(&cache->refcnt.dirty);
+	context->flags.freeze = true;
 
 	ocf_refcnt_register_zero_cb(&cache->refcnt.dirty,
 			_ocf_mngt_begin_flush_complete, context);
 }
 
-static void _ocf_mngt_end_flush(ocf_cache_t cache)
-{
-	ocf_refcnt_unfreeze(&cache->refcnt.dirty);
-
-	env_mutex_unlock(&cache->flush_mutex);
-}
-
 bool ocf_mngt_core_is_dirty(ocf_core_t core)
 {
 	return !!env_atomic_read(&core->runtime_meta->dirty_clines);
@@ -606,7 +609,11 @@ static void _ocf_mngt_flush_finish(ocf_pipeline_t pipeline, void *priv,
 	ocf_cache_t cache = context->cache;
 	ocf_core_t core = context->core;
 
-	_ocf_mngt_end_flush(cache);
+	if (context->flags.freeze)
+		ocf_refcnt_unfreeze(&cache->refcnt.dirty);
+
+	if (context->flags.lock)
+		env_mutex_unlock(&cache->flush_mutex);
 
 	switch (context->op) {
 	case flush_cache:
diff --git a/tests/functional/pyocf/types/shared.py b/tests/functional/pyocf/types/shared.py
index 70d7f49..5244b4d 100644
--- a/tests/functional/pyocf/types/shared.py
+++ b/tests/functional/pyocf/types/shared.py
@@ -41,6 +41,7 @@ class OcfErrorCode(IntEnum):
     OCF_ERR_DIRTY_SHUTDOWN = auto()
     OCF_ERR_DIRTY_EXISTS = auto()
     OCF_ERR_FLUSHING_INTERRUPTED = auto()
+    OCF_ERR_FLUSH_IN_PROGRESS = auto()
     OCF_ERR_CANNOT_ADD_CORE_TO_POOL = auto()
     OCF_ERR_CACHE_IN_INCOMPLETE_STATE = auto()
     OCF_ERR_CORE_IN_INACTIVE_STATE = auto()