diff --git a/2020301918-李懋良-试点班第6个报告.docx b/2020301918-李懋良-试点班第6个报告.docx
new file mode 100644
index 0000000..936cf21
Binary files /dev/null and b/2020301918-李懋良-试点班第6个报告.docx differ
diff --git a/kern/fork.c b/kern/fork.c
index 479e3bd..f340b86 100644
--- a/kern/fork.c
+++ b/kern/fork.c
@@ -127,6 +127,7 @@ kern_fork(PROCESS_0 *p_fa)
 		xchg(&p_fa->lock, 0);
 		return -EAGAIN;
 	}
+	assert(proc_child->pcb.lock == 0);
 	while (xchg(&proc_child->pcb.lock, 1) == 1)
 		schedule();
 	PROCESS_0 *p_child = &proc_child->pcb;
@@ -150,7 +151,7 @@ kern_fork(PROCESS_0 *p_fa)
 	// p_fa shares the same base addr as its padding
 	// anyways, copy the whole proc_table item(8K?)
 	DISABLE_INT(); // make sure this process is never interrupted
-	memset(proc_child, 0, sizeof(PROCESS)); // clear child's kernel stack
+	// memset(proc_child, 0, sizeof(PROCESS)); // clear child's kernel stack //? seem to be useless
 	// the commented fields below will be set later
 	// p_child->cr3
 	p_child->exit_code = p_fa->exit_code;
@@ -163,7 +164,7 @@ kern_fork(PROCESS_0 *p_fa)
 	p_child->statu = INITING; //! important!!! if you copied this from parent, haha, waste one hour
 	p_child->ticks = p_fa->ticks;
 	p_child->user_regs = p_fa->user_regs;
-	ENABLE_INT();
+	ENABLE_INT(); // TODO: may be a useless atomic block, try to remove and test again
 	//?   2. ALLOC PAGES AND COPY PHYSICAL MEMORY
 	copy_parent_pages(p_child, p_fa);
 	// panic("Unimplement! soul torture1");
diff --git a/kern/wait.c b/kern/wait.c
index e958e5d..1c66c21 100644
--- a/kern/wait.c
+++ b/kern/wait.c
@@ -21,18 +21,6 @@ on failure, -1 is returned.
 ssize_t
 kern_wait(int *wstatus)
 {
-	// 相比于fork来说，wait的实现简单很多
-	// 语义实现比较清晰，没有fork那么多难点要处理，所以这里并不会给大家太多引导
-	// 需要大家自己思考wait怎么实现。
-
-	// 在实现之前你必须得读一遍文档`man 2 wait`
-	// 了解到wait大概要做什么
-	// panic("Unimplement! Read The F**king Manual");
-
-	// 当然读文档是一方面，最重要的还是代码实现
-	// wait系统调用与exit系统调用关系密切，所以在实现wait之前需要先读一遍exit为好
-	// 可能读完exit的代码你可能知道wait该具体做什么了
-	// panic("Unimplement! Read The F**king Source Code");
 again:
 	while (xchg(&p_proc_ready->pcb.lock, 1) == 1)
 		schedule();
@@ -44,8 +32,6 @@ again:
 		return -ECHILD;
 	}
 	assert(p_son->pre == NULL); // make sure it is the head of the list
-	while (p_son != NULL) {
-		if (p_son->p_son->statu == ZOMBIE) {
 /*
 struct s_proc {
 user_regs; // let it be
@@ -61,6 +47,8 @@ ticks; // let it be
 fork_tree; // already cleared
 };
 */
+	while (p_son != NULL) {
+		if (p_son->p_son->statu == ZOMBIE) {
 			while (xchg(&p_son->p_son->lock, 1) == 1)
 				schedule();
 			// just use this value, which is '(status & 0xFF) << 8' in exit.c::do_exit
@@ -68,8 +56,6 @@ fork_tree; // already cleared
 				*wstatus = p_son->p_son->exit_code;
 			// recycle_pages in pmap.c
 			recycle_pages(p_son->p_son->page_list);
-			// free it in proc table, 'cause in fork I judge free by statu
-			p_son->p_son->statu = IDLE; 
 			// remove p_son from p_fa's son list
 			if (p_son->pre != NULL) {
 				p_son->pre->nxt = p_son->nxt;
@@ -82,14 +68,16 @@ fork_tree; // already cleared
 			}
 			// keep p_son's pid for retval, 'cause the pointer will get freed before return
 			child_pid = p_son->p_son->pid;
-			xchg(&p_son->p_son->lock, 0);
 			kfree(p_son);
+			// free it in proc table, 'cause in fork I judge free by statu
+			xchg(&proc_table[child_pid].pcb.lock, 0);
+			proc_table[child_pid].pcb.statu = IDLE; // ! set status be the last state, or die
 			goto done;
 		}
 		p_son = p_son->nxt;
 	}
-	p_fa->statu = SLEEP;
 	xchg(&p_fa->lock, 0);
+	p_fa->statu = SLEEP; //! sleep after release lock, or it will deadlock
 	schedule();
 	goto again;
 	// 接下来就是你自己的实现了，我们在设计的时候这段代码不会有太大问题