diff --git a/kernel/host.c b/kernel/host.c
index c84cbeae..e78c5295 100644
--- a/kernel/host.c
+++ b/kernel/host.c
@@ -132,7 +132,8 @@ int prepare_process_ranges_args_envs(struct thread *thread,
 		} 
 		
 		up = virt_to_phys(up_v);
-		if (add_process_memory_range(vm, s, e, up, flags, NULL, 0) != 0) {
+		if (add_process_memory_range(vm, s, e, up, flags, NULL, 0,
+					PAGE_SHIFT) != 0) {
 			ihk_mc_free_pages(up_v, range_npages);
 			kprintf("ERROR: adding memory range for ELF section %i\n", i);
 			goto err;
@@ -211,7 +212,7 @@ int prepare_process_ranges_args_envs(struct thread *thread,
 	args_envs_p = virt_to_phys(args_envs);
 
 	if(add_process_memory_range(vm, addr, e, args_envs_p,
-				flags, NULL, 0) != 0){
+				flags, NULL, 0, PAGE_SHIFT) != 0){
 		ihk_mc_free_pages(args_envs, ARGENV_PAGE_COUNT);
 		kprintf("ERROR: adding memory range for args/envs\n");
 		goto err;
diff --git a/kernel/include/process.h b/kernel/include/process.h
index 8a4cb5a5..d5b170ab 100644
--- a/kernel/include/process.h
+++ b/kernel/include/process.h
@@ -298,6 +298,8 @@ struct vm_range {
 	unsigned long flag;
 	struct memobj *memobj;
 	off_t objoff;
+	int pgshift;	/* page size. 0 means THP */
+	int padding;
 };
 
 struct vm_regions {
@@ -588,7 +590,7 @@ int populate_process_memory(struct process_vm *vm, void *start, size_t len);
 int add_process_memory_range(struct process_vm *vm,
                              unsigned long start, unsigned long end,
                              unsigned long phys, unsigned long flag,
-			     struct memobj *memobj, off_t objoff);
+			     struct memobj *memobj, off_t objoff, int pgshift);
 int remove_process_memory_range(struct process_vm *vm, unsigned long start,
 		unsigned long end, int *ro_freedp);
 int split_process_memory_range(struct process_vm *vm,
diff --git a/kernel/process.c b/kernel/process.c
index e5818657..70f9d3d1 100644
--- a/kernel/process.c
+++ b/kernel/process.c
@@ -983,7 +983,8 @@ enum ihk_mc_pt_attribute common_vrflag_to_ptattr(unsigned long flag, uint64_t fa
 int add_process_memory_range(struct process_vm *vm,
                              unsigned long start, unsigned long end,
                              unsigned long phys, unsigned long flag,
-			     struct memobj *memobj, off_t offset)
+			     struct memobj *memobj, off_t offset,
+			     int pgshift)
 {
 	struct vm_range *range;
 	int rc;
@@ -1011,6 +1012,7 @@ int add_process_memory_range(struct process_vm *vm,
 	range->flag = flag;
 	range->memobj = memobj;
 	range->objoff = offset;
+	range->pgshift = pgshift;
 
     if(range->flag & VR_DEMAND_PAGING) {
 	dkprintf("range: 0x%lX - 0x%lX => physicall memory area is allocated on demand (%ld) [%lx]\n",
@@ -1756,7 +1758,7 @@ int init_process_stack(struct thread *thread, struct program_load_desc *pn,
 	vrflag |= VR_MAXPROT_READ | VR_MAXPROT_WRITE | VR_MAXPROT_EXEC;
 #define	NOPHYS	((uintptr_t)-1)
 	if ((rc = add_process_memory_range(thread->vm, start, end, NOPHYS,
-					vrflag, NULL, 0)) != 0) {
+					vrflag, NULL, 0, PAGE_SHIFT)) != 0) {
 		return rc;
 	}
 
@@ -1869,7 +1871,8 @@ unsigned long extend_process_region(struct process_vm *vm,
 				return end;
 			}
 			if((rc = add_process_memory_range(vm, old_aligned_end,
-                                        aligned_end, virt_to_phys(p), flag)) != 0){
+                                        aligned_end, virt_to_phys(p), flag,
+					LARGE_PAGE_SHIFT)) != 0){
 				free_pages(p, (aligned_end - old_aligned_end) >> PAGE_SHIFT);
 				return end;
 			}
@@ -1899,7 +1902,7 @@ unsigned long extend_process_region(struct process_vm *vm,
 
 		if((rc = add_process_memory_range(vm, aligned_end,
                                aligned_new_end, virt_to_phys((void *)p_aligned),
-                               flag)) != 0){
+                               flag, LARGE_PAGE_SHIFT)) != 0){
 			free_pages(p, (aligned_new_end - aligned_end + LARGE_PAGE_SIZE) >> PAGE_SHIFT);
 			return end;
 		}
@@ -1925,7 +1928,8 @@ unsigned long extend_process_region(struct process_vm *vm,
 	}
     }
 	if((rc = add_process_memory_range(vm, aligned_end, aligned_new_end,
-                                      (p==0?0:virt_to_phys(p)), flag, NULL, 0)) != 0){
+                                      (p==0?0:virt_to_phys(p)), flag, NULL, 0,
+				      PAGE_SHIFT)) != 0){
 		free_pages(p, (aligned_new_end - aligned_end) >> PAGE_SHIFT);
 		return end;
 	}
diff --git a/kernel/syscall.c b/kernel/syscall.c
index efbc0dbf..ae328363 100644
--- a/kernel/syscall.c
+++ b/kernel/syscall.c
@@ -1117,7 +1117,8 @@ do_mmap(const intptr_t addr0, const size_t len0, const int prot,
 	}
 	vrflags |= VRFLAG_PROT_TO_MAXPROT(PROT_TO_VR_FLAG(maxprot));
 
-	error = add_process_memory_range(thread->vm, addr, addr+len, phys, vrflags, memobj, off);
+	error = add_process_memory_range(thread->vm, addr, addr+len, phys,
+			vrflags, memobj, off, PAGE_SHIFT);
 	if (error) {
 		ekprintf("do_mmap:add_process_memory_range"
 				"(%p,%lx,%lx,%lx,%lx) failed %d\n",
@@ -3756,7 +3757,8 @@ SYSCALL_DECLARE(shmat)
 
 	memobj_ref(&obj->memobj);
 
-	error = add_process_memory_range(thread->vm, addr, addr+len, -1, vrflags, &obj->memobj, 0);
+	error = add_process_memory_range(thread->vm, addr, addr+len, -1,
+			vrflags, &obj->memobj, 0, PAGE_SHIFT);
 	if (error) {
 		if (!(prot & PROT_WRITE)) {
 			(void)set_host_vma(addr, len, PROT_READ|PROT_WRITE);
@@ -6457,7 +6459,8 @@ SYSCALL_DECLARE(mremap)
 		}
 		error = add_process_memory_range(thread->vm, newstart, newend, -1,
 				range->flag, range->memobj,
-				range->objoff + (oldstart - range->start));
+				range->objoff + (oldstart - range->start),
+				range->pgshift);
 		if (error) {
 			ekprintf("sys_mremap(%#lx,%#lx,%#lx,%#x,%#lx):"
 					"add failed. %d\n",