diff --git a/lab4/.gdbinit b/lab4/.gdbinit
index 8371cbe..38ac1f7 100644
--- a/lab4/.gdbinit
+++ b/lab4/.gdbinit
@@ -13,4 +13,4 @@ define add-symbol-file-auto
 end
 
 add-symbol-file-auto ./build/kernel.img
-add-symbol-file-auto ./user/build/ramdisk/yield_multi_aff.bin
+add-symbol-file-auto ./user/build/ramdisk/spawn_info.bin
diff --git a/lab4/kernel/sched/policy_rr.c b/lab4/kernel/sched/policy_rr.c
index 4e57fb9..2ea1e99 100644
--- a/lab4/kernel/sched/policy_rr.c
+++ b/lab4/kernel/sched/policy_rr.c
@@ -144,8 +144,8 @@ struct thread *rr_sched_choose_thread(void)
         return NULL;
     }
 
-    kdebug("[RR] Cpu #%d Select thread %lx, sp = %lx\n",
-           smp_get_cpu_id(), result->thread_ctx, result->thread_ctx->ec.reg[SP_EL0]);
+//    kdebug("[RR] Cpu #%d Select thread %lx, sp = %lx\n",
+//           smp_get_cpu_id(), result->thread_ctx, result->thread_ctx->ec.reg[SP_EL0]);
 	return result;
 }
 
@@ -179,7 +179,7 @@ int rr_sched(void)
         // 若非空闲线程，放入队列
         if (current_thread->thread_ctx->type != TYPE_IDLE) {
             rr_sched_enqueue(current_thread);
-            kdebug("[RR] Cpu #%d yield thread %lx to queue\n", smp_get_cpu_id(), current_thread->thread_ctx);
+//            kdebug("[RR] Cpu #%d yield thread %lx to queue\n", smp_get_cpu_id(), current_thread->thread_ctx);
         }
     }
 
diff --git a/lab4/user/lib/spawn.c b/lab4/user/lib/spawn.c
index 501b779..72904cd 100644
--- a/lab4/user/lib/spawn.c
+++ b/lab4/user/lib/spawn.c
@@ -259,8 +259,8 @@ int launch_process_with_pmos_caps(struct user_elf *user_elf,
 		 * process.
 		 *  You do not need to modify code in this scope
 		 */
-		pmo_requests[0].size = LAB4_SPAWN_BLANK;
-		pmo_requests[0].type = LAB4_SPAWN_BLANK;
+		pmo_requests[0].size = MAIN_THREAD_STACK_SIZE;
+		pmo_requests[0].type = PMO_DATA;
 
 		ret = usys_create_pmos((void *)pmo_requests, 1);
 		if (ret != 0) {
@@ -284,7 +284,7 @@ int launch_process_with_pmos_caps(struct user_elf *user_elf,
 		 * Transfer the capbilities (nr_caps) of current process to the
 		 * capbilities of child process
 		 */
-
+        // 将需要转移的 Caps 进行转移
 		if (nr_caps > 0) {
 			/* usys_transfer_caps is used during process creation */
 			ret = usys_transfer_caps(new_process_cap, caps, nr_caps,
@@ -302,7 +302,8 @@ int launch_process_with_pmos_caps(struct user_elf *user_elf,
 		 * Use the given pmo_mao_reqs to map the vmspace in the child
 		 * process
 		 */
-		if (nr_pmo_map_reqs) {
+		// 将参数中需要映射子进程的 PMOs 进行映射，即可实现共享内存
+		if (nr_pmo_map_reqs > 0) {
 			ret =
 			    usys_map_pmos(new_process_cap, (void *)pmo_map_reqs,
 					  nr_pmo_map_reqs);
@@ -329,13 +330,13 @@ int launch_process_with_pmos_caps(struct user_elf *user_elf,
 		 * thread's stack?
 		 *
 		 * For stack_offset, when the main thread gets
-		 * to execute the first time, what's the virtual adress the sp
+		 * to execute the first time, what's the virtual address the sp
 		 * register points to?
 		 * stack_offset is the offset from main thread's stack base to
 		 * that address.
 		 */
-		stack_top = LAB4_SPAWN_BLANK;
-		stack_offset = LAB4_SPAWN_BLANK;
+		stack_top = MAIN_THREAD_STACK_BASE + MAIN_THREAD_STACK_SIZE;
+		stack_offset = MAIN_THREAD_STACK_SIZE - PAGE_SIZE;
 
 		/* Construct the parameters on the top page of the stack */
 		construct_init_env(init_env, stack_top, &user_elf->elf_meta,
@@ -364,9 +365,9 @@ int launch_process_with_pmos_caps(struct user_elf *user_elf,
 		 *  map the the main thread stack's pmo in the new process.
 		 *  Both VM_READ and VM_WRITE permission should be set.
 		 */
-		pmo_map_requests[0].pmo_cap = LAB4_SPAWN_BLANK;
-		pmo_map_requests[0].addr = LAB4_SPAWN_BLANK;
-		pmo_map_requests[0].perm = LAB4_SPAWN_BLANK;
+		pmo_map_requests[0].pmo_cap = main_stack_cap;
+		pmo_map_requests[0].addr = MAIN_THREAD_STACK_BASE;
+		pmo_map_requests[0].perm = VM_READ | VM_WRITE;
 
 		ret =
 		    usys_map_pmos(new_process_cap, (void *)pmo_map_requests, 1);
@@ -384,7 +385,7 @@ int launch_process_with_pmos_caps(struct user_elf *user_elf,
 		 * create main thread in the new process.
 		 * Please fill the stack_va!
 		 */
-		stack_va = LAB4_SPAWN_BLANK;
+		stack_va = MAIN_THREAD_STACK_BASE + stack_offset;
 		main_thread_cap =
 		    usys_create_thread(new_process_cap, stack_va, pc,
 				       (u64) NULL, MAIN_THREAD_PRIO, aff);
@@ -397,6 +398,12 @@ int launch_process_with_pmos_caps(struct user_elf *user_elf,
 
 	{
 		/* Step C: Output the child process & thread capabilities */
+		if (child_process_cap != NULL) {
+
+		}
+		if (child_main_thread_cap != NULL) {
+
+		}
 	}
 
 	return 0;
diff --git a/note.org b/note.org
index c2349a2..20e017d 100644
--- a/note.org
+++ b/note.org
@@ -211,3 +211,9 @@ sys_yield 要注意必须手动调用切换上下文，不然不会有效果。
 *** 练习8
 
 否则将无法再次在该核上进行调度。
+
+*** 练习15
+
+Step A、B 的代码完全没有删干净，而且 A、B 描述都是反的。所以写完练习 14 就可以直接通过 spawn info 了。
+
+我还以为乱码是我又映射错了，结果是代码真的是这么设计的，好吧。