diff --git a/ch2/user/src/bin/01hello_world.rs b/ch2/user/src/bin/01hello_world.rs
deleted file mode 100644
index 1e0f9bc..0000000
--- a/ch2/user/src/bin/01hello_world.rs
+++ /dev/null
@@ -1,10 +0,0 @@
-#![no_std]
-#![no_main]
-
-use user_lib::*;
-
-#[no_mangle]
-fn main() -> i32 {
-    println!("hello 2");
-    0
-}
\ No newline at end of file
diff --git a/ch2/user/src/bin/01store_fault.rs b/ch2/user/src/bin/01store_fault.rs
new file mode 100644
index 0000000..f8023eb
--- /dev/null
+++ b/ch2/user/src/bin/01store_fault.rs
@@ -0,0 +1,15 @@
+#![no_std]
+#![no_main]
+
+#[macro_use]
+extern crate user_lib;
+
+#[no_mangle]
+fn main() -> i32 {
+    println!("Into Test store_fault, we will insert an invalid store operation...");
+    println!("Kernel should kill this application!");
+    unsafe {
+        core::ptr::null_mut::<u8>().write_volatile(0);
+    }
+    0
+}
diff --git a/ch2/user/src/bin/02power.rs b/ch2/user/src/bin/02power.rs
new file mode 100644
index 0000000..f628f34
--- /dev/null
+++ b/ch2/user/src/bin/02power.rs
@@ -0,0 +1,27 @@
+#![no_std]
+#![no_main]
+
+#[macro_use]
+extern crate user_lib;
+
+const SIZE: usize = 10;
+const P: u32 = 3;
+const STEP: usize = 100000;
+const MOD: u32 = 10007;
+
+#[no_mangle]
+fn main() -> i32 {
+    let mut pow = [0u32; SIZE];
+    let mut index: usize = 0;
+    pow[index] = 1;
+    for i in 1..=STEP {
+        let last = pow[index];
+        index = (index + 1) % SIZE;
+        pow[index] = last * P % MOD;
+        if i % 10000 == 0 {
+            println!("{}^{}={}(MOD {})", P, i, pow[index], MOD);
+        }
+    }
+    println!("Test power OK!");
+    0
+}
diff --git a/ch2/user/src/bin/03priv_inst.rs b/ch2/user/src/bin/03priv_inst.rs
new file mode 100644
index 0000000..04dac37
--- /dev/null
+++ b/ch2/user/src/bin/03priv_inst.rs
@@ -0,0 +1,17 @@
+#![no_std]
+#![no_main]
+
+#[macro_use]
+extern crate user_lib;
+
+use core::arch::asm;
+
+#[no_mangle]
+fn main() -> i32 {
+    println!("Try to execute privileged instruction in U Mode");
+    println!("Kernel should kill this application!");
+    unsafe {
+        asm!("sret");
+    }
+    0
+}
diff --git a/ch2/user/src/bin/04priv_csr.rs b/ch2/user/src/bin/04priv_csr.rs
new file mode 100644
index 0000000..fbd678f
--- /dev/null
+++ b/ch2/user/src/bin/04priv_csr.rs
@@ -0,0 +1,17 @@
+#![no_std]
+#![no_main]
+
+#[macro_use]
+extern crate user_lib;
+
+use riscv::register::sstatus::{self, SPP};
+
+#[no_mangle]
+fn main() -> i32 {
+    println!("Try to access privileged CSR in U Mode");
+    println!("Kernel should kill this application!");
+    unsafe {
+        sstatus::set_spp(SPP::User);
+    }
+    0
+}