diff --git a/components/lwp/arch/aarch64/cortex-a/lwp_arch.c b/components/lwp/arch/aarch64/cortex-a/lwp_arch.c
index 630a9565a6bc..c5e4d4b2fcbb 100644
--- a/components/lwp/arch/aarch64/cortex-a/lwp_arch.c
+++ b/components/lwp/arch/aarch64/cortex-a/lwp_arch.c
@@ -51,11 +51,6 @@ void *arch_kernel_mmu_table_get(void)
     return (void *)NULL;
 }
 
-/**
- * @brief vtable is allocated by `arch_user_space_init`
- * and is free by aspace delete
- * @param lwp 
- */
 void arch_user_space_vtable_free(struct rt_lwp *lwp)
 {
     if (lwp && lwp->aspace->page_table)
diff --git a/components/lwp/lwp_user_mm.c b/components/lwp/lwp_user_mm.c
index 9795e9099181..4b9a7cb584c8 100644
--- a/components/lwp/lwp_user_mm.c
+++ b/components/lwp/lwp_user_mm.c
@@ -47,8 +47,9 @@ int lwp_user_space_init(struct rt_lwp *lwp, rt_bool_t is_fork)
         if (!is_fork && err == RT_EOK)
         {
             void *addr = (void *)USER_STACK_VSTART;
-            err = rt_aspace_map(lwp->aspace, &addr, USER_STACK_VEND - USER_STACK_VSTART,
-                        MMU_MAP_U_RWCB, 0, &lwp->lwp_obj->mem_obj, 0);
+            err = rt_aspace_map(lwp->aspace, &addr,
+                                USER_STACK_VEND - USER_STACK_VSTART,
+                                MMU_MAP_U_RWCB, 0, &lwp->lwp_obj->mem_obj, 0);
         }
     }
     return err;
@@ -96,7 +97,7 @@ static const char *user_get_name(rt_varea_t varea)
             name = "user.stack";
         }
         else if (varea->start >= (void *)USER_HEAP_VADDR &&
-                varea->start < (void *)USER_HEAP_VEND)
+                 varea->start < (void *)USER_HEAP_VEND)
         {
             name = "user.heap";
         }
@@ -135,8 +136,8 @@ static void user_page_fault(struct rt_varea *varea, struct mm_fault_msg *msg)
                 }
                 else
                 {
-                    LOG_W("%s: page alloc failed at %p", __func__, 
-                        varea->start);
+                    LOG_W("%s: page alloc failed at %p", __func__,
+                          varea->start);
                 }
             }
             else
@@ -148,7 +149,6 @@ static void user_page_fault(struct rt_varea *varea, struct mm_fault_msg *msg)
                 msg->response.vaddr = vaddr;
                 msg->response.size = ARCH_PAGE_SIZE;
             }
-    
         }
         else if (!(varea->flag & MMF_TEXT))
         {
@@ -185,8 +185,8 @@ static void *_lwp_map_user(struct rt_lwp *lwp, void *map_va, size_t map_size,
     rt_mem_obj_t mem_obj = &lwp->lwp_obj->mem_obj;
     va = map_va ? map_va : ARCH_MAP_FAILED;
 
-    ret = rt_aspace_map(lwp->aspace, &va, map_size, MMU_MAP_U_RWCB,
-                        flags, mem_obj, 0);
+    ret = rt_aspace_map(lwp->aspace, &va, map_size, MMU_MAP_U_RWCB, flags,
+                        mem_obj, 0);
     if (ret != MM_EOK)
     {
         va = RT_NULL;
@@ -204,7 +204,8 @@ int lwp_unmap_user(struct rt_lwp *lwp, void *va)
     return err;
 }
 
-static void _dup_varea(rt_varea_t varea, struct rt_lwp *src_lwp, rt_aspace_t dst)
+static void _dup_varea(rt_varea_t varea, struct rt_lwp *src_lwp,
+                       rt_aspace_t dst)
 {
     void *vaddr = varea->start;
     void *vend = vaddr + varea->size;
@@ -262,7 +263,7 @@ int lwp_dup_user(rt_varea_t varea, void *arg)
         int err;
         va = varea->start;
         err = rt_aspace_map(new_lwp->aspace, &va, varea->size, varea->attr,
-                            varea->flag, &new_lwp->lwp_obj->mem_obj, 
+                            varea->flag, &new_lwp->lwp_obj->mem_obj,
                             varea->offset);
         if (err != MM_EOK)
         {
@@ -338,7 +339,7 @@ static void *_lwp_map_user_type(struct rt_lwp *lwp, void *map_va, void *map_pa,
         attr = MMU_MAP_U_RW;
     }
 
-    struct rt_mem_obj *mem_obj = lwp->lwp_obj ? &lwp->lwp_obj->mem_obj: NULL;
+    struct rt_mem_obj *mem_obj = lwp->lwp_obj ? &lwp->lwp_obj->mem_obj : NULL;
 
     if (map_pa == ARCH_MAP_FAILED)
     {
@@ -350,10 +351,10 @@ static void *_lwp_map_user_type(struct rt_lwp *lwp, void *map_va, void *map_pa,
         if (!map_va)
             map_va = ARCH_MAP_FAILED;
         struct rt_mm_va_hint hint = {.flags = 0,
-                                    .limit_range_size = lwp->aspace->size,
-                                    .limit_start = lwp->aspace->start,
-                                    .prefer = map_va,
-                                    .map_size = map_size};
+                                     .limit_range_size = lwp->aspace->size,
+                                     .limit_start = lwp->aspace->start,
+                                     .prefer = map_va,
+                                     .map_size = map_size};
         ret = rt_aspace_map_phy(lwp->aspace, &hint, attr,
                                 (uintptr_t)map_pa >> MM_PAGE_SHIFT, &map_va);
     }
diff --git a/components/mm/mm_aspace.c b/components/mm/mm_aspace.c
index 2501c082f087..11614750d3a9 100644
--- a/components/mm/mm_aspace.c
+++ b/components/mm/mm_aspace.c
@@ -68,7 +68,7 @@ static inline void _varea_post_install(rt_varea_t varea, rt_aspace_t aspace,
         varea->mem_obj->on_varea_open(varea);
 }
 
-rt_err_t _init_lock(rt_aspace_t aspace)
+int _init_lock(rt_aspace_t aspace)
 {
     MM_PGTBL_LOCK_INIT(aspace);
     rt_mutex_init(&aspace->bst_lock, "", RT_IPC_FLAG_FIFO);
@@ -224,11 +224,11 @@ static int _do_prefetch(rt_aspace_t aspace, rt_varea_t varea, void *start,
     return err;
 }
 
-rt_err_t _varea_install(rt_aspace_t aspace, rt_varea_t varea,
+int _varea_install(rt_aspace_t aspace, rt_varea_t varea,
                         rt_mm_va_hint_t hint)
 {
     void *alloc_va;
-    rt_err_t err = RT_EOK;
+    int err = RT_EOK;
 
     /**
      * find a suitable va range.
@@ -253,11 +253,11 @@ rt_err_t _varea_install(rt_aspace_t aspace, rt_varea_t varea,
     return err;
 }
 
-static rt_err_t _mm_aspace_map(rt_aspace_t aspace, rt_varea_t varea,
+static int _mm_aspace_map(rt_aspace_t aspace, rt_varea_t varea,
                                size_t attr, mm_flag_t flags,
                                rt_mem_obj_t mem_obj, size_t offset)
 {
-    rt_err_t err = RT_EOK;
+    int err = RT_EOK;
 
     WR_LOCK(aspace);
     struct rt_mm_va_hint hint = {.prefer = varea->start,
@@ -312,12 +312,12 @@ static inline int _not_support(size_t flags)
     return flags & ~(support_ops | _MMF_ALIGN_MASK);
 }
 
-rt_err_t rt_aspace_map(rt_aspace_t aspace, void **addr, size_t length,
+int rt_aspace_map(rt_aspace_t aspace, void **addr, size_t length,
                        size_t attr, mm_flag_t flags, rt_mem_obj_t mem_obj,
                        size_t offset)
 {
     // TODO check not in atomic context: irq, spinlock, local intr disable...
-    rt_err_t err;
+    int err;
     rt_varea_t varea;
 
     // filter invalid input
@@ -357,7 +357,7 @@ rt_err_t rt_aspace_map(rt_aspace_t aspace, void **addr, size_t length,
     return err;
 }
 
-rt_err_t rt_aspace_map_static(rt_aspace_t aspace, rt_varea_t varea, void **addr,
+int rt_aspace_map_static(rt_aspace_t aspace, rt_varea_t varea, void **addr,
                               size_t length, size_t attr, mm_flag_t flags,
                               rt_mem_obj_t mem_obj, size_t offset)
 {
@@ -392,11 +392,11 @@ rt_err_t rt_aspace_map_static(rt_aspace_t aspace, rt_varea_t varea, void **addr,
     return err;
 }
 
-rt_err_t _mm_aspace_map_phy(rt_aspace_t aspace, rt_varea_t varea,
+int _mm_aspace_map_phy(rt_aspace_t aspace, rt_varea_t varea,
                             rt_mm_va_hint_t hint, size_t attr, size_t pa_off,
                             void **ret_va)
 {
-    rt_err_t err;
+    int err;
     void *vaddr;
 
     // filter invalid input
@@ -444,10 +444,10 @@ rt_err_t _mm_aspace_map_phy(rt_aspace_t aspace, rt_varea_t varea,
     return err;
 }
 
-rt_err_t rt_aspace_map_phy(rt_aspace_t aspace, rt_mm_va_hint_t hint, size_t attr,
+int rt_aspace_map_phy(rt_aspace_t aspace, rt_mm_va_hint_t hint, size_t attr,
                            size_t pa_off, void **ret_va)
 {
-    rt_err_t err;
+    int err;
 
     if (hint)
     {
@@ -473,11 +473,11 @@ rt_err_t rt_aspace_map_phy(rt_aspace_t aspace, rt_mm_va_hint_t hint, size_t attr
     return err;
 }
 
-rt_err_t rt_aspace_map_phy_static(rt_aspace_t aspace, rt_varea_t varea,
+int rt_aspace_map_phy_static(rt_aspace_t aspace, rt_varea_t varea,
                                   rt_mm_va_hint_t hint, size_t attr,
                                   size_t pa_off, void **ret_va)
 {
-    rt_err_t err;
+    int err;
 
     if (varea && hint)
     {
@@ -520,7 +520,7 @@ void _aspace_unmap(rt_aspace_t aspace, void *addr, size_t length)
     }
 }
 
-rt_err_t rt_aspace_unmap(rt_aspace_t aspace, void *addr, size_t length)
+int rt_aspace_unmap(rt_aspace_t aspace, void *addr, size_t length)
 {
     if (!aspace)
     {
diff --git a/components/mm/mm_aspace.h b/components/mm/mm_aspace.h
index 4a7d143d008c..5b59d4ea84f3 100644
--- a/components/mm/mm_aspace.h
+++ b/components/mm/mm_aspace.h
@@ -163,7 +163,7 @@ int rt_aspace_map_static(rt_aspace_t aspace, rt_varea_t varea, void **addr,
 
 /**
  * @brief Memory Map on Virtual Address Space to Physical Memory
- * 
+ *
  * @param aspace target virtual address space
  * @param hint hint of mapping va
  * @param attr MMU attribution
diff --git a/components/mm/mm_page.c b/components/mm/mm_page.c
index d634049b5225..f72ed3d129a9 100644
--- a/components/mm/mm_page.c
+++ b/components/mm/mm_page.c
@@ -17,7 +17,6 @@
 
 #include "mm_fault.h"
 #include "mm_private.h"
-#include "mm_rmem.h"
 #include <mm_aspace.h>
 #include <mm_flag.h>
 #include <mm_page.h>
diff --git a/components/mm/mm_page.h b/components/mm/mm_page.h
index d619a2ac8c28..68641ab4153d 100644
--- a/components/mm/mm_page.h
+++ b/components/mm/mm_page.h
@@ -68,7 +68,7 @@ struct rt_page *rt_page_addr2page(void *addr);
 /**
  * @brief Install page frames at run-time
  * Region size must be aligned to 2^(RT_PAGE_MAX_ORDER + ARCH_PAGE_SHIFT - 1)
- * bytes currently (typically 2 MB). 
+ * bytes currently (typically 2 MB).
  *
  * !WARNING this API will NOT check whether region is valid or not in list
  *
diff --git a/libcpu/arm/cortex-a/mmu.c b/libcpu/arm/cortex-a/mmu.c
index 827865ed4b13..9931dd6a16fc 100644
--- a/libcpu/arm/cortex-a/mmu.c
+++ b/libcpu/arm/cortex-a/mmu.c
@@ -331,21 +331,6 @@ void rt_hw_mmu_unmap(rt_aspace_t aspace, void *v_addr, size_t size)
     }
 }
 
-/*
-    orr r0, #0x18
-    mcr p15, 0, r0, c2, c0, 0       // ttbr0
-
-                                    //invalid tlb
-    mov r0, #0
-    mcr p15, 0, r0, c8, c7, 0
-    mcr p15, 0, r0, c7, c5, 0       //iciallu
-    mcr p15, 0, r0, c7, c5, 6       //bpiall 
-
-    dsb
-    isb
-    mov pc, lr
-*/
-
 void rt_hw_aspace_switch(rt_aspace_t aspace)
 {
     if (aspace != &rt_kernel_space)
diff --git a/libcpu/risc-v/t-head/c906/riscv_mmu.h b/libcpu/risc-v/t-head/c906/riscv_mmu.h
index bb54d0959580..1459ad488dd8 100644
--- a/libcpu/risc-v/t-head/c906/riscv_mmu.h
+++ b/libcpu/risc-v/t-head/c906/riscv_mmu.h
@@ -65,7 +65,7 @@
 
 #define PTE_USED(pte) __MASKVALUE(pte, PTE_V)
 
-/** 
+/**
  * encoding of SATP (Supervisor Address Translation and Protection register)
  */
 #define SATP_MODE_OFFSET    60
diff --git a/libcpu/risc-v/virt64/riscv_mmu.h b/libcpu/risc-v/virt64/riscv_mmu.h
index 623af18eee55..fc5a143b65bd 100644
--- a/libcpu/risc-v/virt64/riscv_mmu.h
+++ b/libcpu/risc-v/virt64/riscv_mmu.h
@@ -58,7 +58,7 @@
 
 #define PTE_USED(pte) __MASKVALUE(pte, PTE_V)
 
-/** 
+/**
  * encoding of SATP (Supervisor Address Translation and Protection register)
  */
 #define SATP_MODE_OFFSET    60