diff --git a/os/src/task/mod.rs b/os/src/task/mod.rs
index 009829e7..4a98094a 100644
--- a/os/src/task/mod.rs
+++ b/os/src/task/mod.rs
@@ -49,12 +49,12 @@ lazy_static! {
 impl TaskManager {
     fn run_first_task(&self) {
         self.inner.borrow_mut().tasks[0].task_status = TaskStatus::Running;
-        let next_task_cx = self.inner.borrow().tasks[0].get_task_cx_ptr2();
+        let next_task_cx_ptr2 = self.inner.borrow().tasks[0].get_task_cx_ptr2();
         let _unused: usize = 0;
         unsafe {
             __switch(
                 &_unused as *const _,
-                next_task_cx,
+                next_task_cx_ptr2,
             );
         }
     }
@@ -99,13 +99,13 @@ impl TaskManager {
             let current = inner.current_task;
             inner.tasks[next].task_status = TaskStatus::Running;
             inner.current_task = next;
-            let current_task_cx = inner.tasks[current].get_task_cx_ptr2();
-            let next_task_cx = inner.tasks[next].get_task_cx_ptr2();
+            let current_task_cx_ptr2 = inner.tasks[current].get_task_cx_ptr2();
+            let next_task_cx_ptr2 = inner.tasks[next].get_task_cx_ptr2();
             core::mem::drop(inner);
             unsafe {
                 __switch(
-                    current_task_cx,
-                    next_task_cx,
+                    current_task_cx_ptr2,
+                    next_task_cx_ptr2,
                 );
             }
         } else {
diff --git a/os/src/task/switch.S b/os/src/task/switch.S
index df668f35..262511fe 100644
--- a/os/src/task/switch.S
+++ b/os/src/task/switch.S
@@ -8,7 +8,10 @@
     .section .text
     .globl __switch
 __switch:
-    # __switch(current_task_cx: &*const TaskContext, next_task_cx: &*const TaskContext)
+    # __switch(
+    #     current_task_cx_ptr2: &*const TaskContext,
+    #     next_task_cx_ptr2: &*const TaskContext
+    # )
     # push TaskContext to current sp and save its address to where a0 points to
     addi sp, sp, -13*8
     sd sp, 0(a0)
diff --git a/os/src/task/switch.rs b/os/src/task/switch.rs
index c5fe5f47..867fcb1e 100644
--- a/os/src/task/switch.rs
+++ b/os/src/task/switch.rs
@@ -1,5 +1,8 @@
 global_asm!(include_str!("switch.S"));
 
 extern "C" {
-    pub fn __switch(current_task_cx: *const usize, next_task_cx: *const usize);
+    pub fn __switch(
+        current_task_cx_ptr2: *const usize,
+        next_task_cx_ptr2: *const usize
+    );
 }