diff --git a/crate/memory/src/swap/fifo.rs b/crate/memory/src/swap/fifo.rs
index 03ab226..80ca368 100644
--- a/crate/memory/src/swap/fifo.rs
+++ b/crate/memory/src/swap/fifo.rs
@@ -13,12 +13,12 @@ impl SwapManager for FifoSwapManager {
     fn tick(&mut self) {}
 
     fn push(&mut self, frame: Frame) {
-        debug!("SwapManager push token: {:x?} vaddr: {:x?}", frame.get_token(), frame.get_virtaddr());
+        info!("SwapManager push token: {:x?} vaddr: {:x?}", frame.get_token(), frame.get_virtaddr());
         self.deque.push_back(frame);
     }
 
     fn remove(&mut self, token: usize, addr: VirtAddr) {
-        debug!("SwapManager remove token: {:x?} vaddr: {:x?}", token, addr);
+        info!("SwapManager remove token: {:x?} vaddr: {:x?}", token, addr);
         let id = self.deque.iter()
             .position(|ref x| x.get_virtaddr() == addr && x.get_token() == token)
             .expect("address not found");
diff --git a/crate/memory/src/swap/mod.rs b/crate/memory/src/swap/mod.rs
index cd2f09a..19c566e 100644
--- a/crate/memory/src/swap/mod.rs
+++ b/crate/memory/src/swap/mod.rs
@@ -113,7 +113,7 @@ impl<T: PageTable, M: SwapManager, S: Swapper> SwapExt<T, M, S> {
         let Self {ref mut page_table, ref mut swap_manager, ref mut swapper} = self;
         let targetpt = &mut *(pt);
         let pttoken = {
-            debug!("the target page table token is {:x?}", targetpt.token());
+            info!("SET_SWAPPABLE: the target page table token is {:x?}, addr is {:x?}", targetpt.token(), addr);
             targetpt.token()
         };
         targetpt.with(||{
@@ -139,14 +139,14 @@ impl<T: PageTable, M: SwapManager, S: Swapper> SwapExt<T, M, S> {
     **  @param alloc_frame:          the function to alloc a free physical frame for once
     */
     pub unsafe fn remove_from_swappable<T2: InactivePageTable>(&mut self, pt: *mut T2, addr: VirtAddr, alloc_frame: impl FnOnce() -> PhysAddr){
-        trace!("come into remove_from swappable");
+        info!("come into remove_from swappable");
         let Self {ref mut page_table, ref mut swap_manager, ref mut swapper} = self;
         let targetpt = &mut *(pt);
         let pttoken = {
             debug!("the target page table token is {:x?}", targetpt.token());
             targetpt.token()
         };
-        debug!("try to change pagetable");
+        info!("try to change pagetable");
         targetpt.with(||{
             let token = {
                 let entry = page_table.get_entry(addr);
@@ -169,7 +169,7 @@ impl<T: PageTable, M: SwapManager, S: Swapper> SwapExt<T, M, S> {
             let data = page_table.get_page_slice_mut(addr);
             swapper.swap_in(token, data).unwrap();
         });
-        trace!("come outof femove_from swappable");
+        trace!("come out of femove_from swappable");
     }
 
     /*
@@ -301,7 +301,7 @@ impl<T: PageTable, M: SwapManager, S: Swapper> SwapExt<T, M, S> {
                 }
                 if(swapin){
                     unsafe {
-                        self.set_swappable(pt, addr);
+                        self.set_swappable(pt, addr & 0xfffff000);
                     }
                 }
                 //area.get_flags().apply(new_entry); this instruction may be used when hide attr is used
diff --git a/crate/process/src/process_manager.rs b/crate/process/src/process_manager.rs
index 63878c1..988d56d 100644
--- a/crate/process/src/process_manager.rs
+++ b/crate/process/src/process_manager.rs
@@ -225,7 +225,7 @@ impl ProcessManager {
             self.wakeup(*waiter);
         }
 
-        //proc.context = None;
+        proc.context = None;
     }
 }
  fn new_vec_default<T: Default>(size: usize) -> Vec<T> {
diff --git a/crate/riscv b/crate/riscv
index f358204..a37a65f 160000
--- a/crate/riscv
+++ b/crate/riscv
@@ -1 +1 @@
-Subproject commit f358204af01f2374ab6ed6ea059f724cd5f2fe6f
+Subproject commit a37a65fa13a00c5aa0068c3f2b5d55af6a37dd93
diff --git a/docs/OSTrain2018docs-g4/expr4/lcy-labguide.md b/docs/OSTrain2018docs-g4/expr4/lcy-labguide.md
new file mode 100644
index 0000000..e69de29
diff --git a/kernel/src/process/context.rs b/kernel/src/process/context.rs
index 5168c45..b80dee4 100644
--- a/kernel/src/process/context.rs
+++ b/kernel/src/process/context.rs
@@ -130,7 +130,7 @@ impl ContextImpl {
         let mut memory_set = self.memory_set.clone();
         info!("finish mmset clone in fork!");
         // add the new memory set to the recorder
-        debug!("fork! new page table token: {:x?}", memory_set.token());
+        info!("fork! new page table token: {:x?}", memory_set.token());
         let mmset_ptr = ((&mut memory_set) as * mut MemorySet) as usize;
         memory_set_record().push_back(mmset_ptr);
         
@@ -179,6 +179,7 @@ impl ContextImpl {
 
 impl Drop for ContextImpl{
     fn drop(&mut self){
+        info!("come in to drop for ContextImpl");
         // remove the new memory set to the recorder (deprecated in the latest version)
         /*
         let id = memory_set_record().iter()
@@ -251,6 +252,7 @@ fn memory_attr_from(elf_flags: Flags) -> MemoryAttr {
 *   map the memory area in the memory_set swappalbe, specially for the user process
 */
 pub fn memory_set_map_swappable(memory_set: &mut MemorySet){
+    info!("COME INTO memory set map swappable!");
     let pt = unsafe {
         memory_set.get_page_table_mut() as *mut InactivePageTable0
     };