diff --git a/os/src/boards/qemu.rs b/os/src/boards/qemu.rs
index 92d4f37..93d1bad 100644
--- a/os/src/boards/qemu.rs
+++ b/os/src/boards/qemu.rs
@@ -1,10 +1,10 @@
 pub const CLOCK_FREQ: usize = 12500000;
 
 pub const MMIO: &[(usize, usize)] = &[
-//    (0x0010_0000, 0x00_2000), // VIRT_TEST/RTC  in virt machine
+    //    (0x0010_0000, 0x00_2000), // VIRT_TEST/RTC  in virt machine
     (0x2000000, 0x10000),
     (0xc000000, 0x210000), // VIRT_PLIC in virt machine
-    (0x10000000, 0x9000), // VIRT_UART0 with GPU  in virt machine
+    (0x10000000, 0x9000),  // VIRT_UART0 with GPU  in virt machine
 ];
 
 pub type BlockDeviceImpl = crate::drivers::block::VirtIOBlock;
@@ -25,7 +25,7 @@ pub fn device_init() {
     let machine = IntrTargetPriority::Machine;
     plic.set_threshold(hart_id, supervisor, 0);
     plic.set_threshold(hart_id, machine, 1);
-    for intr_src_id in [1usize, 10] {
+    for intr_src_id in [8usize, 10] {
         plic.enable(hart_id, supervisor, intr_src_id);
         plic.set_priority(intr_src_id, 1);
     }
@@ -38,7 +38,7 @@ pub fn irq_handler() {
     let mut plic = unsafe { PLIC::new(VIRT_PLIC) };
     let intr_src_id = plic.claim(0, IntrTargetPriority::Supervisor);
     match intr_src_id {
-        1 => BLOCK_DEVICE.handle_irq(),
+        8 => BLOCK_DEVICE.handle_irq(),
         10 => UART.handle_irq(),
         _ => panic!("unsupported IRQ {}", intr_src_id),
     }
diff --git a/os/src/main.rs b/os/src/main.rs
index e328e8e..3b84c24 100644
--- a/os/src/main.rs
+++ b/os/src/main.rs
@@ -32,7 +32,7 @@ mod task;
 mod timer;
 mod trap;
 
-use syscall::create_desktop;
+// use syscall::create_desktop; //for test
 
 core::arch::global_asm!(include_str!("entry.asm"));
 
@@ -71,7 +71,7 @@ pub fn rust_main() -> ! {
     timer::set_next_trigger();
     board::device_init();
     fs::list_apps();
-    syscall::create_desktop();
+    //syscall::create_desktop(); //for test
     task::add_initproc();
     *DEV_NON_BLOCKING_ACCESS.exclusive_access() = true;
     task::run_tasks();