diff --git a/README.md b/README.md
index 68662e2..aba47c5 100644
--- a/README.md
+++ b/README.md
@@ -1,3 +1,7 @@
 # CS130 Project - pintos
 
-ShanghaiTech University Spring 2024.
\ No newline at end of file
+ShanghaiTech University Spring 2024.
+
+## No plagiarism
+
+If you are enrolled in CS130, you may not copy source code from this repository.
\ No newline at end of file
diff --git a/pintos/src/examples/.gitignore b/pintos/src/examples/.gitignore
index a9e09d7..d5a1a73 100644
--- a/pintos/src/examples/.gitignore
+++ b/pintos/src/examples/.gitignore
@@ -17,3 +17,5 @@ lineup
 matmult
 recursor
 *.d
+*.o
+*.a
diff --git a/pintos/src/threads/thread.c b/pintos/src/threads/thread.c
index fd4ce11..8f262d3 100644
--- a/pintos/src/threads/thread.c
+++ b/pintos/src/threads/thread.c
@@ -83,6 +83,7 @@ static long long user_ticks;    /* # of timer ticks in user programs. */
 /* Scheduling. */
 #define TIME_SLICE 4            /* # of timer ticks to give each thread. */
 static unsigned thread_ticks;   /* # of timer ticks since last yield. */
+static bool scheduler_init;     /* Denote whether the schedular should work. */
 
 /* If false (default), use round-robin scheduler.
    If true, use multi-level feedback queue scheduler.
@@ -148,6 +149,8 @@ thread_start (void)
 
   /* Wait for the idle thread to initialize idle_thread. */
   sema_down (&idle_started);
+
+  scheduler_init = true;
 }
 
 /* Called by the timer interrupt handler at each timer tick.
@@ -364,6 +367,9 @@ thread_exit (void)
 void
 thread_yield (void) 
 {
+  if (!scheduler_init)
+    return;
+
   struct thread *cur = thread_current ();
   enum intr_level old_level;
   
diff --git a/pintos/src/userprog/remake.sh b/pintos/src/userprog/remake.sh
new file mode 100755
index 0000000..fae2d60
--- /dev/null
+++ b/pintos/src/userprog/remake.sh
@@ -0,0 +1,9 @@
+#!/bin/bash
+
+make clean
+make
+cd build/
+pintos-mkdisk filesys.dsk --filesys-size=2
+cd ..
+
+echo "userprog/ clean & rebuild."
\ No newline at end of file
diff --git a/pintos/src/utils/Pintos.pm b/pintos/src/utils/Pintos.pm
index 0139aba..70df40d 100644
--- a/pintos/src/utils/Pintos.pm
+++ b/pintos/src/utils/Pintos.pm
@@ -359,7 +359,7 @@ sub cyl_sectors {
 # Makes sure that the loader is a reasonable size.
 sub read_loader {
     my ($name) = @_;
-    $name = find_file ("/home/asta/ShanghaiTech/2024Spring/CS130-Project/pintos/src/threads/build/loader.bin") if !defined $name;
+    $name = find_file ("loader.bin") if !defined $name;
     die "Cannot find loader\n" if !defined $name;
 
     my ($handle);
diff --git a/pintos/src/utils/pintos b/pintos/src/utils/pintos
index 1690ff5..7374c6d 100755
--- a/pintos/src/utils/pintos
+++ b/pintos/src/utils/pintos
@@ -257,7 +257,7 @@ sub set_disk {
 sub find_disks {
     # Find kernel, if we don't already have one.
     if (!exists $parts{KERNEL}) {
-	my $name = find_file ('/home/asta/ShanghaiTech/2024Spring/CS130-Project/pintos/src/threads/build/kernel.bin');
+	my $name = find_file ('kernel.bin');
 	die "Cannot find kernel\n" if !defined $name;
 	do_set_part ('KERNEL', 'file', $name);
     }
diff --git a/pintos/src/utils/setitimer-helper.o b/pintos/src/utils/setitimer-helper.o
deleted file mode 100644
index c1f5edd..0000000
Binary files a/pintos/src/utils/setitimer-helper.o and /dev/null differ
diff --git a/pintos/src/utils/squish-pty.o b/pintos/src/utils/squish-pty.o
deleted file mode 100644
index 48b8d9c..0000000
Binary files a/pintos/src/utils/squish-pty.o and /dev/null differ
diff --git a/pintos/src/utils/squish-unix.o b/pintos/src/utils/squish-unix.o
deleted file mode 100644
index bc38ea6..0000000
Binary files a/pintos/src/utils/squish-unix.o and /dev/null differ