Environment variables WIP, fix waiting scheduling issues + CE cancel proc

kernel/proc/proc.h

@@ -21,8 +21,7 @@
 
 /* process states */
 #define PROC_READY     0
-#define PROC_DEAD      1
-#define PROC_SUSPENDED 2
+#define PROC_SUSPENDED 1
 
 /* process flags */
 #define PROC_USTK_PREALLOC (1 << 0)
@@ -34,6 +33,7 @@ struct reschedule_ctx;
 struct proc {
   int pid;
   int exec_pid;
+  struct list_node_link reaper_list_link;
   struct rb_node_link proc_tree_link;
   struct rb_node_link procgroup_memb_tree_link;
   struct list_node_link cpu_run_q_link;
@@ -44,6 +44,7 @@ struct proc {
   spin_lock_t lock;
   struct cpu* cpu;
   int state;
+  bool dead;
   uintptr_t uvaddr_argument;
   void* mail_recv_buffer;
   size_t mail_recv_size;