diff --git a/kernel/src/process/process_vm/mod.rs b/kernel/src/process/process_vm/mod.rs
index 38cf1251..12ebcc39 100644
--- a/kernel/src/process/process_vm/mod.rs
+++ b/kernel/src/process/process_vm/mod.rs
@@ -83,11 +83,6 @@ impl ProcessVmarGuard<'_> {
         self.inner.as_ref().unwrap()
     }
 
-    /// Sets a new VMAR for the binding process.
-    pub(super) fn set_new_vmar(&mut self, new_vmar: Vmar<Full>) {
-        *self.inner = Some(new_vmar);
-    }
-
     /// Clears the VMAR of the binding process.
     pub(super) fn clear(&mut self) {
         *self.inner = None;
diff --git a/ostd/src/mm/kspace/kvirt_area.rs b/ostd/src/mm/kspace/kvirt_area.rs
index d12c8ea5..daf432f2 100644
--- a/ostd/src/mm/kspace/kvirt_area.rs
+++ b/ostd/src/mm/kspace/kvirt_area.rs
@@ -5,8 +5,6 @@
 use alloc::collections::BTreeMap;
 use core::{any::TypeId, marker::PhantomData, ops::Range};
 
-use align_ext::AlignExt;
-
 use super::{KERNEL_PAGE_TABLE, TRACKED_MAPPED_PAGES_RANGE, VMALLOC_VADDR_RANGE};
 use crate::{
     cpu::CpuSet,
@@ -188,11 +186,15 @@ impl<M: AllocatorSelector + 'static> KVirtArea<M> {
         self.range.start..self.range.end
     }
 
+    #[cfg(ktest)]
     pub fn len(&self) -> usize {
         self.range.len()
     }
 
+    #[cfg(ktest)]
     fn query_page(&self, addr: Vaddr) -> PageTableItem {
+        use align_ext::AlignExt;
+
         assert!(self.start() <= addr && self.end() >= addr);
         let start = addr.align_down(PAGE_SIZE);
         let vaddr = start..start + PAGE_SIZE;
@@ -232,6 +234,7 @@ impl KVirtArea<Tracked> {
     ///
     /// This function returns None if the address is not mapped (`NotMapped`),
     /// while panics if the address is mapped to a `MappedUntracked` or `PageTableNode` page.
+    #[cfg(ktest)]
     pub fn get_page(&self, addr: Vaddr) -> Option<Frame<dyn AnyFrameMeta>> {
         let query_result = self.query_page(addr);
         match query_result {
@@ -288,6 +291,7 @@ impl KVirtArea<Untracked> {
     ///
     /// This function returns None if the address is not mapped (`NotMapped`),
     /// while panics if the address is mapped to a `Mapped` or `PageTableNode` page.
+    #[cfg(ktest)]
     pub fn get_untracked_page(&self, addr: Vaddr) -> Option<(Paddr, usize)> {
         let query_result = self.query_page(addr);
         match query_result {
diff --git a/ostd/src/mm/kspace/mod.rs b/ostd/src/mm/kspace/mod.rs
index 2472b023..2ff5e716 100644
--- a/ostd/src/mm/kspace/mod.rs
+++ b/ostd/src/mm/kspace/mod.rs
@@ -1,7 +1,5 @@
 // SPDX-License-Identifier: MPL-2.0
 
-#![expect(dead_code)]
-
 //! Kernel memory space management.
 //!
 //! The kernel memory space is currently managed as follows, if the