diff --git a/Makefile b/Makefile
index 72f72f9..dbc4674 100644
--- a/Makefile
+++ b/Makefile
@@ -26,10 +26,10 @@ OBJS = \
 	vectors.o\
 
 # Cross-compiling (e.g., on Mac OS X)
-# TOOLPREFIX = i386-jos-elf-
+TOOLPREFIX = i386-jos-elf-
 
 # Using native tools (e.g., on X86 Linux)
-TOOLPREFIX = 
+#TOOLPREFIX = 
 
 CC = $(TOOLPREFIX)gcc
 AS = $(TOOLPREFIX)gas
diff --git a/proc.c b/proc.c
index cf982c1..614a130 100644
--- a/proc.c
+++ b/proc.c
@@ -325,7 +325,6 @@ wakeup1(void *chan)
 }
 
 // Wake up all processes sleeping on chan.
-// Proc_table_lock is acquired and released.
 void
 wakeup(void *chan)
 {
diff --git a/xv6-rev2.tar.gz b/xv6-rev2.tar.gz
index f334fa0..be6e390 100644
Binary files a/xv6-rev2.tar.gz and b/xv6-rev2.tar.gz differ