diff --git a/kernel/aster-nix/src/fs/devpts/mod.rs b/kernel/aster-nix/src/fs/devpts/mod.rs
index 305a29dab..0eaacd9cb 100644
--- a/kernel/aster-nix/src/fs/devpts/mod.rs
+++ b/kernel/aster-nix/src/fs/devpts/mod.rs
@@ -41,18 +41,17 @@ const MAX_PTY_NUM: usize = 4096;
 ///
 /// Actually, the "/dev/ptmx" is a symlink to the real device at "/dev/pts/ptmx".
 pub struct DevPts {
-    root: Arc<RootInode>,
     sb: SuperBlock,
+    root: Arc<RootInode>,
     index_alloc: Mutex<IdAlloc>,
     this: Weak<Self>,
 }
 
 impl DevPts {
     pub fn new() -> Arc<Self> {
-        let sb = SuperBlock::new(DEVPTS_MAGIC, BLOCK_SIZE, NAME_MAX);
         Arc::new_cyclic(|weak_self| Self {
-            root: RootInode::new(weak_self.clone(), &sb),
-            sb,
+            sb: SuperBlock::new(DEVPTS_MAGIC, BLOCK_SIZE, NAME_MAX),
+            root: RootInode::new(weak_self.clone()),
             index_alloc: Mutex::new(IdAlloc::with_capacity(MAX_PTY_NUM)),
             this: weak_self.clone(),
         })
@@ -112,14 +111,14 @@ struct RootInode {
 }
 
 impl RootInode {
-    pub fn new(fs: Weak<DevPts>, sb: &SuperBlock) -> Arc<Self> {
+    pub fn new(fs: Weak<DevPts>) -> Arc<Self> {
         Arc::new(Self {
-            ptmx: Ptmx::new(sb, fs.clone()),
+            ptmx: Ptmx::new(fs.clone()),
             slaves: RwLock::new(SlotVec::new()),
             metadata: RwLock::new(Metadata::new_dir(
                 ROOT_INO,
                 InodeMode::from_bits_truncate(0o755),
-                sb,
+                BLOCK_SIZE,
             )),
             fs,
         })
diff --git a/kernel/aster-nix/src/fs/devpts/ptmx.rs b/kernel/aster-nix/src/fs/devpts/ptmx.rs
index 959e7ccee..5565261d9 100644
--- a/kernel/aster-nix/src/fs/devpts/ptmx.rs
+++ b/kernel/aster-nix/src/fs/devpts/ptmx.rs
@@ -24,13 +24,13 @@ pub struct Ptmx {
 struct Inner(Weak<DevPts>);
 
 impl Ptmx {
-    pub fn new(sb: &SuperBlock, fs: Weak<DevPts>) -> Arc<Self> {
+    pub fn new(fs: Weak<DevPts>) -> Arc<Self> {
         let inner = Inner(fs);
         Arc::new(Self {
             metadata: RwLock::new(Metadata::new_device(
                 PTMX_INO,
                 InodeMode::from_bits_truncate(0o666),
-                sb,
+                super::BLOCK_SIZE,
                 &inner,
             )),
             inner,
diff --git a/kernel/aster-nix/src/fs/devpts/slave.rs b/kernel/aster-nix/src/fs/devpts/slave.rs
index 19d788005..4d2f5f1ae 100644
--- a/kernel/aster-nix/src/fs/devpts/slave.rs
+++ b/kernel/aster-nix/src/fs/devpts/slave.rs
@@ -24,7 +24,7 @@ impl PtySlaveInode {
             metadata: RwLock::new(Metadata::new_device(
                 device.index() as usize + FIRST_SLAVE_INO,
                 InodeMode::from_bits_truncate(0o620),
-                &fs.upgrade().unwrap().sb(),
+                super::BLOCK_SIZE,
                 device.as_ref(),
             )),
             device,