diff --git a/common_components/heap/space/nonmovable_space.cpp b/common_components/heap/space/nonmovable_space.cpp
index e5217d3e455c21616944480608b4b1062984752f..647e4bf4b955f9db2207b4a9b0f2092990b15f66 100644
--- a/common_components/heap/space/nonmovable_space.cpp
+++ b/common_components/heap/space/nonmovable_space.cpp
@@ -128,7 +128,7 @@ uintptr_t NonMovableSpace::Alloc(size_t size, bool allowGC)
     size_t cellCount = size / sizeof(uint64_t) - 1;
     RegionList* list = recentMonoSizeRegionList_[cellCount];
     std::mutex& listMutex = list->GetListMutex();
-    listMutex.lock();
+    std::lock_guard<std::mutex> lock(listMutex);
     RegionDesc* headRegion = list->GetHeadRegion();
     if (headRegion != nullptr) {
         addr = headRegion->Alloc(size);
@@ -140,7 +140,6 @@ uintptr_t NonMovableSpace::Alloc(size_t size, bool allowGC)
         RegionDesc* region =
             regionManager_.TakeRegion(1, RegionDesc::UnitRole::SMALL_SIZED_UNITS, false, allowGC);
         if (region == nullptr) {
-            listMutex.unlock();
             return 0;
         }
         DLOG(REGION, "alloc non-movable region @0x%zx+%zu type %u", region->GetRegionStart(),
@@ -154,7 +153,6 @@ uintptr_t NonMovableSpace::Alloc(size_t size, bool allowGC)
         addr = region->Alloc(size);
     }
     DLOG(ALLOC, "alloc non-movable obj 0x%zx(%zu)", addr, size);
-    listMutex.unlock();
     return addr;
 }
 
diff --git a/common_components/heap/space/regional_space.h b/common_components/heap/space/regional_space.h
index 6f541b6d49b9879d5a091e898fcd74cc539f7181..d8fcef3838cd7dacb3db0dc02ddcdef2e587016d 100644
--- a/common_components/heap/space/regional_space.h
+++ b/common_components/heap/space/regional_space.h
@@ -54,6 +54,9 @@ protected:
 
     void InitRegionPhaseLine(RegionDesc* region)
     {
+        if (region == nullptr) {
+            return;
+        }
         GCPhase phase = Mutator::GetMutator()->GetMutatorPhase();
         if (phase == GC_PHASE_ENUM || phase == GC_PHASE_MARK || phase == GC_PHASE_REMARK_SATB ||
             phase == GC_PHASE_POST_MARK) {