diff --git a/arch/x86/kernel/memory.c b/arch/x86/kernel/memory.c
index 28159839..f85b75e0 100644
--- a/arch/x86/kernel/memory.c
+++ b/arch/x86/kernel/memory.c
@@ -490,8 +490,10 @@ uint64_t ihk_mc_pt_virt_to_pagemap(struct page_table *pt, unsigned long virt)
 	return pagemap;
 }
 
-int ihk_mc_pt_virt_to_phys(struct page_table *pt,
-                           const void *virt, unsigned long *phys)
+int ihk_mc_pt_virt_to_phys_size(struct page_table *pt,
+                           const void *virt,
+						   unsigned long *phys,
+						   unsigned long *size)
 {
 	int l4idx, l3idx, l2idx, l1idx;
 	unsigned long v = (unsigned long)virt;
@@ -513,6 +515,7 @@ int ihk_mc_pt_virt_to_phys(struct page_table *pt,
 	if ((pt->entry[l3idx] & PFL3_SIZE)) {
 		*phys = pte_get_phys(&pt->entry[l3idx])
 			| (v & (PTL3_SIZE - 1));
+		if (size) *size = PTL3_SIZE;
 		return 0;
 	}
 	pt = phys_to_virt(pte_get_phys(&pt->entry[l3idx]));
@@ -523,6 +526,7 @@ int ihk_mc_pt_virt_to_phys(struct page_table *pt,
 	if ((pt->entry[l2idx] & PFL2_SIZE)) {
 		*phys = pte_get_phys(&pt->entry[l2idx])
 			| (v & (PTL2_SIZE - 1));
+		if (size) *size = PTL2_SIZE;
 		return 0;
 	}
 	pt = phys_to_virt(pte_get_phys(&pt->entry[l2idx]));
@@ -532,9 +536,17 @@ int ihk_mc_pt_virt_to_phys(struct page_table *pt,
 	}
 
 	*phys = pte_get_phys(&pt->entry[l1idx]) | (v & (PTL1_SIZE - 1));
+	if (size) *size = PTL1_SIZE;
 	return 0;
 }
 
+int ihk_mc_pt_virt_to_phys(struct page_table *pt,
+                           const void *virt, unsigned long *phys)
+{
+	return ihk_mc_pt_virt_to_phys_size(pt, virt, phys, NULL);
+}
+
+
 int ihk_mc_pt_print_pte(struct page_table *pt, void *virt)
 {
 	int l4idx, l3idx, l2idx, l1idx;
diff --git a/kernel/syscall.c b/kernel/syscall.c
index 9c39a1a5..f8f8378e 100644
--- a/kernel/syscall.c
+++ b/kernel/syscall.c
@@ -7694,6 +7694,7 @@ static int do_process_vm_read_writev(int pid,
 	struct process_vm *rvm = NULL;
 	unsigned long rphys;
 	unsigned long rpage_left;
+	unsigned long psize;
 	void *rva;
 	struct vm_range *range;
 	struct mcs_rwlock_node_irqsave lock;
diff --git a/lib/include/ihk/mm.h b/lib/include/ihk/mm.h
index c8e7c39e..9ceee283 100644
--- a/lib/include/ihk/mm.h
+++ b/lib/include/ihk/mm.h
@@ -164,6 +164,10 @@ struct page_table *ihk_mc_pt_create(enum ihk_mc_ap_flag ap_flag);
 /* XXX: proper use of struct page_table and page_table_t is unknown */
 void ihk_mc_pt_destroy(struct page_table *pt);
 void ihk_mc_load_page_table(struct page_table *pt);
+int ihk_mc_pt_virt_to_phys_size(struct page_table *pt,
+                           const void *virt,
+						   unsigned long *phys,
+						   unsigned long *size);
 int ihk_mc_pt_virt_to_phys(struct page_table *pt,
                            const void *virt, unsigned long *phys);
 uint64_t ihk_mc_pt_virt_to_pagemap(struct page_table *pt, unsigned long virt);