diff --git a/.cargo/config.toml b/kernel/.cargo/config.toml
similarity index 100%
rename from .cargo/config.toml
rename to kernel/.cargo/config.toml
diff --git a/kernel/Cargo.lock b/kernel/Cargo.lock
index 37da659..57404be 100644
--- a/kernel/Cargo.lock
+++ b/kernel/Cargo.lock
@@ -2,6 +2,16 @@
 # It is not intended for manual editing.
 version = 3
 
+[[package]]
+name = "allocator"
+version = "0.1.0"
+dependencies = [
+ "spin 0.9.8",
+ "static_assertions",
+ "utils",
+ "vspace",
+]
+
 [[package]]
 name = "api"
 version = "0.1.0"
@@ -62,6 +72,7 @@ checksum = "784a4df722dc6267a04af36895398f59d21d07dce47232adf31ec0ff2fa45e67"
 name = "kernel"
 version = "0.1.0"
 dependencies = [
+ "allocator",
  "api",
  "bitflags 2.5.0",
  "cfg-if",
@@ -75,6 +86,8 @@ dependencies = [
  "spin 0.9.8",
  "static_assertions",
  "uart_16550",
+ "utils",
+ "vspace",
 ]
 
 [[package]]
@@ -235,6 +248,22 @@ version = "1.0.12"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3354b9ac3fae1ff6755cb6db53683adb661634f67557942dea4facebec0fee4b"
 
+[[package]]
+name = "utils"
+version = "0.1.0"
+dependencies = [
+ "vspace",
+]
+
+[[package]]
+name = "vspace"
+version = "0.1.0"
+dependencies = [
+ "bitflags 2.5.0",
+ "num-derive",
+ "num-traits",
+]
+
 [[package]]
 name = "x86"
 version = "0.52.0"
diff --git a/kernel/Cargo.toml b/kernel/Cargo.toml
index fcdcca0..68b3094 100644
--- a/kernel/Cargo.toml
+++ b/kernel/Cargo.toml
@@ -8,7 +8,7 @@ edition = "2021"
 [features]
 default = ["riscv.board.virt", "log_color"]
 
-legacy = []
+legacy = ["utils/legacy", "vspace/legacy"]
 
 riscv = []
 
@@ -33,9 +33,12 @@ panic = "abort"
 lto = "thin"
 
 [dependencies]
+allocator = { path = "../lib/allocator" }
 api = { path = "../api" }
+utils = { path = "../lib/utils", default-features = false }
+vspace = { path = "../lib/vspace", default-features = false }
 
-bitflags = "2.4"
+bitflags = "2.5"
 cfg-if = "1.0"
 fdt = "0.1"
 lazy_static = { version = "1.4", features = ["spin_no_std"] }
diff --git a/kernel/build.rs b/kernel/build.rs
index d73b97e..d49c770 100644
--- a/kernel/build.rs
+++ b/kernel/build.rs
@@ -9,7 +9,7 @@ fn main() {
     const TARGET_LDS: &[TargetConfig] = &[
         TargetConfig {
             target: "riscv64",
-            lds:    "src/arch/riscv/linker.ld",
+            lds:    "src/arch/riscv/linker64.ld",
         },
         TargetConfig {
             target: "riscv32",
diff --git a/kernel/src/arch/mod.rs b/kernel/src/arch/mod.rs
index 1bfeaa9..6416040 100644
--- a/kernel/src/arch/mod.rs
+++ b/kernel/src/arch/mod.rs
@@ -1,7 +1,4 @@
-pub use arch::*;
-
-// Arch Level
 #[cfg(feature = "riscv")]
-#[path = "riscv/mod.rs"]
-#[allow(clippy::module_inception)]
-mod arch;
+mod riscv;
+#[cfg(feature = "riscv")]
+pub use riscv::*;
diff --git a/kernel/src/arch/riscv/entry.rs b/kernel/src/arch/riscv/entry.rs
index d8fffde..232e5e4 100644
--- a/kernel/src/arch/riscv/entry.rs
+++ b/kernel/src/arch/riscv/entry.rs
@@ -1,9 +1,6 @@
-use super::board::console::init_early_console;
-use super::vspace::utils::setup_kernel_paging;
 use crate::arch::layout::zero_bss;
-use crate::arch::vspace::utils::setup_memory;
-use crate::vspace::allocator::RamBlock;
-use fdt::Fdt;
+use crate::arch::vspace::utils::{setup_kernel_paging, setup_memory};
+use allocator::RamBlock;
 
 #[naked]
 #[no_mangle]
diff --git a/kernel/src/arch/riscv/layout.rs b/kernel/src/arch/riscv/layout.rs
index 4c46416..9559a2b 100644
--- a/kernel/src/arch/riscv/layout.rs
+++ b/kernel/src/arch/riscv/layout.rs
@@ -1,7 +1,7 @@
-use crate::utils::extern_addr::ExternSymbol;
-use crate::utils::size::KIB;
-use crate::vspace::addr::{AddressOps, PhysAddr, VirtAddr};
 use core::alloc::Layout;
+use utils::extern_addr::ExternSymbol;
+use utils::size::KIB;
+use vspace::addr::{AddressOps, PhysAddr, VirtAddr};
 
 extern "C" {
     pub static KERNEL_START: ExternSymbol;
diff --git a/kernel/src/arch/riscv/mod.rs b/kernel/src/arch/riscv/mod.rs
index f3e5130..27af3f8 100644
--- a/kernel/src/arch/riscv/mod.rs
+++ b/kernel/src/arch/riscv/mod.rs
@@ -12,6 +12,7 @@ cfg_if! {
 }
 
 // Console: plat/console.rs
+pub use board::console::init_early_console;
 pub use board::console::EarlyConsole;
 
 mod entry;
diff --git a/kernel/src/arch/riscv/vspace/entry.rs b/kernel/src/arch/riscv/vspace/entry.rs
index 836efdc..23ad2a5 100644
--- a/kernel/src/arch/riscv/vspace/entry.rs
+++ b/kernel/src/arch/riscv/vspace/entry.rs
@@ -1,6 +1,7 @@
-use crate::vspace::addr::{AddressOps, PhysAddr};
-use crate::vspace::paging::{EntryOps, MapAttr};
+use super::traits::PhysAddrPaging;
 use bitflags::bitflags;
+use vspace::addr::PhysAddr;
+use vspace::paging::{EntryOps, MapAttr};
 
 bitflags! {
     #[derive(Debug)]
@@ -79,45 +80,6 @@ assert_eq_size!(Entry, u64);
 #[cfg(feature = "riscv.pagetable.sv32")]
 assert_eq_size!(Entry, u32);
 
-#[cfg(feature = "riscv.pagetable.sv32")]
-impl PhysAddr {
-    const PA_PPN_MASK: usize = ((1 << Self::PPN_BITS) - 1) << Self::PG_OFFSET;
-    const PG_OFFSET: usize = 12;
-    const PPN_BITS: usize = 22;
-    const PPN_OFFSET: usize = 10;
-    const PTE_PPN_MASK: usize = ((1 << Self::PPN_BITS) - 1) << Self::PPN_OFFSET;
-}
-
-#[cfg(feature = "riscv.pagetable.sv39")]
-impl PhysAddr {
-    const PA_PPN_MASK: usize = ((1 << Self::PPN_BITS) - 1) << Self::PG_OFFSET;
-    const PG_OFFSET: usize = 12;
-    const PPN_BITS: usize = 44;
-    const PPN_OFFSET: usize = 10;
-    const PTE_PPN_MASK: usize = ((1 << Self::PPN_BITS) - 1) << Self::PPN_OFFSET;
-}
-
-impl PhysAddr {
-    pub fn to_ppn(self) -> usize {
-        (self.as_usize() & Self::PA_PPN_MASK) >> Self::PG_OFFSET
-    }
-
-    fn to_ppn_shifted(self) -> usize {
-        self.to_ppn() << Self::PPN_OFFSET
-    }
-
-    fn from_pte(pte: usize) -> Self {
-        let ppn = (pte & Self::PTE_PPN_MASK) >> Self::PPN_OFFSET;
-        let paddr = ppn << Self::PG_OFFSET;
-        PhysAddr::from(paddr)
-    }
-
-    fn merge_pte(self, pte: usize) -> usize {
-        let ppn = self.to_ppn_shifted();
-        (pte & !Self::PTE_PPN_MASK) | ppn
-    }
-}
-
 #[derive(Clone, Copy, Default)]
 pub struct Entry(usize);
 
diff --git a/kernel/src/arch/riscv/vspace/mod.rs b/kernel/src/arch/riscv/vspace/mod.rs
index 8e37a61..d05123b 100644
--- a/kernel/src/arch/riscv/vspace/mod.rs
+++ b/kernel/src/arch/riscv/vspace/mod.rs
@@ -1,6 +1,4 @@
 mod entry;
 mod table;
+mod traits;
 pub mod utils;
-
-pub use entry::Entry;
-pub use table::Table;
diff --git a/kernel/src/arch/riscv/vspace/table.rs b/kernel/src/arch/riscv/vspace/table.rs
index 664fc80..2f531f0 100644
--- a/kernel/src/arch/riscv/vspace/table.rs
+++ b/kernel/src/arch/riscv/vspace/table.rs
@@ -1,63 +1,9 @@
+use super::entry::Entry;
+use super::traits::{TableLevelSize, VirtAddrPaging};
 use crate::arch::layout::{kernel_phys_to_virt, PAGE_SIZE};
-use crate::utils::size::*;
-use crate::vspace::addr::*;
-use crate::vspace::paging::*;
 use num_traits::ToPrimitive;
-
-#[cfg(feature = "riscv.pagetable.sv32")]
-impl VirtAddr {
-    const PG_OFFSET: usize = 12;
-    const VPN_BITS: usize = 10;
-    const VPN_MASK: usize = (1 << Self::VPN_BITS) - 1;
-}
-
-#[cfg(feature = "riscv.pagetable.sv39")]
-impl VirtAddr {
-    const PG_OFFSET: usize = 12;
-    const VPN_BITS: usize = 9;
-    const VPN_MASK: usize = (1 << Self::VPN_BITS) - 1;
-}
-
-impl VirtAddr {
-    fn to_vpn(self, level: TableLevel) -> usize {
-        self.0 >> (Self::PG_OFFSET + Self::VPN_BITS * level.to_usize().unwrap()) & Self::VPN_MASK
-    }
-
-    fn merge_vpn(&self, vpn: usize, size: TableLevel) -> Self {
-        let shift = Self::PG_OFFSET + Self::VPN_BITS * size.to_usize().unwrap();
-        let mask = Self::VPN_MASK << shift;
-        VirtAddr((self.0 & !mask) | ((vpn & Self::VPN_MASK) << shift))
-    }
-
-    fn lower_bits(self, level: usize) -> usize {
-        self.0 & ((1 << (Self::PG_OFFSET + Self::VPN_BITS * (level + 1))) - 1)
-    }
-}
-
-impl TableLevel {
-    pub fn level_size(&self) -> usize {
-        match self {
-            Self::Level0 => 4 * KIB,
-            #[cfg(feature = "riscv.pagetable.sv32")]
-            Self::Level1 => 4 * MIB,
-            #[cfg(not(feature = "riscv.pagetable.sv32"))]
-            Self::Level1 => 2 * MIB,
-            Self::Level2 => 1 * GIB,
-            #[cfg(not(feature = "legacy"))]
-            Self::Level3 => 512 * GIB,
-            #[cfg(not(feature = "legacy"))]
-            Self::Level4 => 256 * TIB,
-        }
-    }
-
-    pub fn align<A: AddressOps>(&self, addr: A) -> A {
-        addr.align_down(self.level_size())
-    }
-
-    pub fn is_aligned<A: AddressOps>(&self, addr: A) -> bool {
-        self.align(addr) == addr
-    }
-}
+use vspace::addr::*;
+use vspace::paging::*;
 
 #[repr(C, align(4096))]
 pub struct Table {
@@ -84,6 +30,17 @@ impl Table {
             table = unsafe { Self::new(kernel_phys_to_virt(entry.addr()).as_usize().into()) };
         }
     }
+
+    pub fn mode() -> riscv::register::satp::Mode {
+        #[cfg(feature = "riscv.pagetable.sv32")]
+        return riscv::register::satp::Mode::Sv32;
+        #[cfg(feature = "riscv.pagetable.sv39")]
+        return riscv::register::satp::Mode::Sv39;
+        #[cfg(feature = "riscv.pagetable.sv48")]
+        return riscv::register::satp::Mode::Sv48;
+        #[cfg(feature = "riscv.pagetable.sv57")]
+        return riscv::register::satp::Mode::Sv57;
+    }
 }
 
 impl TableOps for Table {
diff --git a/kernel/src/arch/riscv/vspace/traits.rs b/kernel/src/arch/riscv/vspace/traits.rs
new file mode 100644
index 0000000..231fb47
--- /dev/null
+++ b/kernel/src/arch/riscv/vspace/traits.rs
@@ -0,0 +1,113 @@
+use num_traits::ToPrimitive;
+use utils::size::{GIB, KIB, MIB, TIB};
+use vspace::addr::{AddressOps, PhysAddr, VirtAddr};
+use vspace::paging::TableLevel;
+
+pub trait PhysAddrPaging {
+    const PG_OFFSET: usize;
+    const PPN_BITS: usize;
+    const PPN_OFFSET: usize;
+
+    const PA_PPN_MASK: usize = ((1 << Self::PPN_BITS) - 1) << Self::PG_OFFSET;
+    const PTE_PPN_MASK: usize = ((1 << Self::PPN_BITS) - 1) << Self::PPN_OFFSET;
+
+    fn to_ppn(&self) -> usize
+    where Self: AddressOps {
+        (self.as_usize() & Self::PA_PPN_MASK) >> Self::PG_OFFSET
+    }
+
+    fn to_ppn_shifted(&self) -> usize
+    where Self: PhysAddrPaging + AddressOps {
+        self.to_ppn() << Self::PPN_OFFSET
+    }
+
+    fn from_pte(pte: usize) -> PhysAddr {
+        let ppn = (pte & Self::PTE_PPN_MASK) >> Self::PPN_OFFSET;
+        let paddr = ppn << Self::PG_OFFSET;
+        PhysAddr::from(paddr)
+    }
+
+    fn merge_pte(&self, pte: usize) -> usize
+    where Self: PhysAddrPaging + AddressOps {
+        let ppn = self.to_ppn_shifted();
+        (pte & !Self::PTE_PPN_MASK) | ppn
+    }
+}
+
+#[cfg(feature = "riscv.pagetable.sv32")]
+impl PhysAddrPaging for PhysAddr {
+    const PG_OFFSET: usize = 12;
+    const PPN_BITS: usize = 22;
+    const PPN_OFFSET: usize = 10;
+}
+
+#[cfg(feature = "riscv.pagetable.sv39")]
+impl PhysAddrPaging for PhysAddr {
+    const PG_OFFSET: usize = 12;
+    const PPN_BITS: usize = 44;
+    const PPN_OFFSET: usize = 10;
+}
+
+pub trait VirtAddrPaging {
+    const PG_OFFSET: usize;
+    const VPN_BITS: usize;
+
+    const VPN_MASK: usize = (1 << Self::VPN_BITS) - 1;
+
+    fn to_vpn(&self, level: TableLevel) -> usize
+    where Self: AddressOps {
+        self.as_usize() >> (Self::PG_OFFSET + Self::VPN_BITS * level.to_usize().unwrap())
+            & Self::VPN_MASK
+    }
+
+    fn merge_vpn(&self, vpn: usize, size: TableLevel) -> VirtAddr
+    where Self: AddressOps {
+        let shift = Self::PG_OFFSET + Self::VPN_BITS * size.to_usize().unwrap();
+        let mask = Self::VPN_MASK << shift;
+        VirtAddr((self.as_usize() & !mask) | ((vpn & Self::VPN_MASK) << shift))
+    }
+
+    fn lower_bits(&self, level: usize) -> usize
+    where Self: AddressOps {
+        self.as_usize() & ((1 << (Self::PG_OFFSET + Self::VPN_BITS * (level + 1))) - 1)
+    }
+}
+
+#[cfg(feature = "riscv.pagetable.sv32")]
+impl VirtAddrPaging for VirtAddr {
+    const PG_OFFSET: usize = 12;
+    const VPN_BITS: usize = 10;
+}
+
+#[cfg(feature = "riscv.pagetable.sv39")]
+impl VirtAddrPaging for VirtAddr {
+    const PG_OFFSET: usize = 12;
+    const VPN_BITS: usize = 9;
+}
+
+pub trait TableLevelSize {
+    fn level_size(&self) -> usize;
+    fn align<A: AddressOps>(&self, addr: A) -> A {
+        addr.align_down(self.level_size())
+    }
+    fn is_aligned<A: AddressOps>(&self, addr: A) -> bool {
+        self.align(addr) == addr
+    }
+}
+
+impl TableLevelSize for TableLevel {
+    fn level_size(&self) -> usize {
+        match self {
+            Self::Level0 => 4 * KIB,
+            #[cfg(feature = "riscv.pagetable.sv32")]
+            Self::Level1 => 4 * MIB,
+            #[cfg(not(feature = "riscv.pagetable.sv32"))]
+            Self::Level1 => 2 * MIB,
+            Self::Level2 => 1 * GIB,
+            #[cfg(not(feature = "legacy"))]
+            Self::Level3 => 512 * GIB,
+            #[cfg(not(feature = "legacy"))]
+            Self::Level4 => 256 * TIB,
+        }
+    }
+}
diff --git a/kernel/src/arch/riscv/vspace/utils.rs b/kernel/src/arch/riscv/vspace/utils.rs
index 0790547..004ea7e 100644
--- a/kernel/src/arch/riscv/vspace/utils.rs
+++ b/kernel/src/arch/riscv/vspace/utils.rs
@@ -1,11 +1,15 @@
+use super::table::Table;
+use super::traits::{PhysAddrPaging, TableLevelSize};
 use crate::arch::layout::*;
-use crate::utils::size::GIB;
-use crate::vspace::addr::{align_up, AddressOps, PhysAddr, VirtAddr};
-use crate::vspace::allocator::RamBlock;
-use crate::vspace::paging::PageError::{AlreadyMapped, MissingEntry};
-use crate::vspace::paging::{MapAttr, Table, TableLevel, TableOps};
+use allocator::RamBlock;
+use fdt::Fdt;
+use utils::size::GIB;
+use vspace::addr::*;
+use vspace::paging::{MapAttr, PageError::*, TableLevel, TableOps};
+
+pub unsafe fn setup_memory(fdt_addr: usize, mem: &mut RamBlock<8>) {
+    let fdt = unsafe { Fdt::from_ptr(fdt_addr as *const u8).unwrap() };
 
-pub unsafe fn setup_memory<const N: usize>(fdt: &fdt::Fdt, fdt_addr: usize, mem: &mut RamBlock<N>) {
     // Add main memory regions to allocator
     for region in fdt.memory().regions() {
         mem.dealloc(
@@ -46,7 +50,11 @@ pub unsafe fn setup_memory<const N: usize>(fdt: &fdt::Fdt, fdt_addr: usize, mem:
     mem.reserve(fdt_addr, fdt_size);
 }
 
-pub unsafe fn setup_kernel_paging<const N: usize>(allocator: &mut RamBlock<N>) {
+pub unsafe fn setup_kernel_paging(
+    allocator: &mut RamBlock<8>,
+    hart_id: usize,
+    fdt_addr: usize,
+) -> ! {
     let mut alloc = || {
         allocator
             .alloc(PAGE_LAYOUT)
diff --git a/kernel/src/entry.rs b/kernel/src/entry.rs
index e2e89e1..d1d7aa7 100644
--- a/kernel/src/entry.rs
+++ b/kernel/src/entry.rs
@@ -1,16 +1,19 @@
-use core::cell::Cell;
-use log::{debug, error, info, warn};
-
+use crate::arch::init_early_console;
 use crate::plat::console::{set_console, ConsoleDevice, ConsoleDriver, CONSOLE};
 use crate::plat::lowlevel::{Hardware, LowLevel};
 use crate::plat::timer::{Timer, TimerOps};
 use crate::plat::trap::{Trap, TrapOps};
-use crate::vspace::allocator::RamBlock;
+use allocator::RamBlock;
+use core::cell::Cell;
+use fdt::Fdt;
+use log::{debug, error, info, warn};
 
 #[thread_local]
 pub static HART_ID: Cell<usize> = Cell::new(0);
 
-pub fn rust_main<const N: usize>(hart_id: usize, fdt: fdt::Fdt, mut _allocator: RamBlock<N>) -> ! {
+// NOTE: we will call rust_main through trap (stvec), make sure it is aligned
+#[repr(align(4))]
+pub extern "C" fn rust_main(hart_id: usize, fdt_addr: usize, allocator: &mut RamBlock<8>) -> ! {
     HART_ID.set(hart_id);
 
     info!("Kernel Started");
diff --git a/kernel/src/main.rs b/kernel/src/main.rs
index f369301..237be05 100644
--- a/kernel/src/main.rs
+++ b/kernel/src/main.rs
@@ -6,10 +6,10 @@
 #![feature(concat_idents)]
 #![feature(const_mut_refs)]
 #![feature(extern_types)]
+#![feature(fn_align)]
 #![feature(let_chains)]
 #![feature(naked_functions)]
 #![feature(panic_info_message)]
-#![feature(step_trait)]
 #![feature(stmt_expr_attributes)]
 #![feature(thread_local)]
 // Test Infrastructure
@@ -21,9 +21,6 @@
 #[macro_use]
 extern crate static_assertions;
 
-#[macro_use]
-extern crate num_derive;
-
 mod arch;
 mod drivers;
 mod entry;
@@ -31,8 +28,6 @@ mod lang;
 mod logging;
 mod objects;
 mod plat;
-mod utils;
-mod vspace;
 
 // test infrastructure
 #[cfg(test)]
diff --git a/kernel/src/vspace/mod.rs b/kernel/src/vspace/mod.rs
deleted file mode 100644
index 2bb91c2..0000000
--- a/kernel/src/vspace/mod.rs
+++ /dev/null
@@ -1,3 +0,0 @@
-pub mod addr;
-pub mod allocator;
-pub mod paging;