diff --git a/src/arch/aarch64/device/serial.rs b/src/arch/aarch64/device/serial.rs
index a6dd8d6..d4abe9d 100644
--- a/src/arch/aarch64/device/serial.rs
+++ b/src/arch/aarch64/device/serial.rs
@@ -10,27 +10,27 @@ use crate::paging::{ActivePageTable, Page, PageFlags, PhysicalAddress, TableKind
 pub static COM1: Mutex<Option<SerialPort>> = Mutex::new(None);
 
 pub unsafe fn init() {
-    if let Some(ref mut serial_port) = *COM1.lock() {
-        return;
+    if COM1.lock().is_none() {
+        let (base, size) = device_tree::diag_uart_range(crate::KERNEL_DTB_OFFSET, crate::KERNEL_DTB_MAX_SIZE).unwrap();
+
+        let mut active_ktable = unsafe { ActivePageTable::new(TableKind::Kernel) };
+        let mut flush_all = PageFlushAll::new();
+
+        let start_frame = Frame::containing_address(PhysicalAddress::new(base));
+        let end_frame = Frame::containing_address(PhysicalAddress::new(base + size - 1));
+        for frame in Frame::range_inclusive(start_frame, end_frame) {
+            let page = Page::containing_address(VirtualAddress::new(frame.start_address().data() + crate::KERNEL_DEVMAP_OFFSET));
+            let result = active_ktable.map_to(page, frame, PageFlags::new().write(true));
+            flush_all.consume(result);
+        };
+        flush_all.flush();
+
+        let start_frame = Frame::containing_address(PhysicalAddress::new(base));
+        let vaddr = start_frame.start_address().data() + crate::KERNEL_DEVMAP_OFFSET;
+
+        *COM1.lock() = Some(SerialPort::new(vaddr));
     }
-    let (base, size) = device_tree::diag_uart_range(crate::KERNEL_DTB_OFFSET, crate::KERNEL_DTB_MAX_SIZE).unwrap();
 
-    let mut active_ktable = unsafe { ActivePageTable::new(TableKind::Kernel) };
-    let mut flush_all = PageFlushAll::new();
-
-    let start_frame = Frame::containing_address(PhysicalAddress::new(base));
-    let end_frame = Frame::containing_address(PhysicalAddress::new(base + size - 1));
-    for frame in Frame::range_inclusive(start_frame, end_frame) {
-        let page = Page::containing_address(VirtualAddress::new(frame.start_address().data() + crate::KERNEL_DEVMAP_OFFSET));
-        let result = active_ktable.map_to(page, frame, PageFlags::new().write(true));
-        flush_all.consume(result);
-    };
-    flush_all.flush();
-
-    let start_frame = Frame::containing_address(PhysicalAddress::new(base));
-    let vaddr = start_frame.start_address().data() + crate::KERNEL_DEVMAP_OFFSET;
-
-    *COM1.lock() = Some(SerialPort::new(vaddr));
     if let Some(ref mut serial_port) = *COM1.lock() {
         serial_port.init(true);
     }