even more explicit that entry.S is linked into kernel, unlike bootasm.S.

entry.S

@@ -1,3 +1,7 @@
+# The xv6 kernel starts executing in this file. This file is linked with
+# the kernel C code, so it can refer to kernel symbols such as main().
+# The boot block (bootasm.S and bootmain.c) jumps to entry below.
+        
 # Multiboot header, for multiboot boot loaders like GNU Grub.
 # http://www.gnu.org/software/grub/manual/multiboot/multiboot.html
 #

entryother.S

@@ -53,7 +53,7 @@ start32:
   movl    %cr4, %eax
   orl     $(CR4_PSE), %eax
   movl    %eax, %cr4
-  # Use enterpgdir as our initial page table
+  # Use entrypgdir as our initial page table
   movl    (start-12), %eax
   movl    %eax, %cr3
   # Turn on paging.