Index: kernel/tools/genmap.py
===================================================================
--- kernel/tools/genmap.py	(revision afe1d1e203e5c589222f7579368f84a24d325f3c)
+++ kernel/tools/genmap.py	(revision 432f68a8331e076e5531a65e1516a67ad37318ab)
@@ -100,8 +100,9 @@
 			for addr, symbol in symbols:
 				value = fname + ':' + symbol
-				data = struct.pack(symtabfmt, addr + offset, value[:MAXSTRING])
+				value_bytes = value.encode('ascii')
+				data = struct.pack(symtabfmt, addr + offset, value_bytes[:MAXSTRING])
 				out.write(data)
 			
-	out.write(struct.pack(symtabfmt, 0, ''))
+	out.write(struct.pack(symtabfmt, 0, b''))
 
 def main():
Index: tools/mkfat.py
===================================================================
--- tools/mkfat.py	(revision afe1d1e203e5c589222f7579368f84a24d325f3c)
+++ tools/mkfat.py	(revision 432f68a8331e076e5531a65e1516a67ad37318ab)
@@ -211,6 +211,6 @@
 	dir_entry = xstruct.create(DIR_ENTRY)
 	
-	dir_entry.name = mangle_fname(name)
-	dir_entry.ext = mangle_ext(name)
+	dir_entry.name = mangle_fname(name).encode('ascii')
+	dir_entry.ext = mangle_ext(name).encode('ascii')
 	
 	if (directory):
@@ -239,6 +239,6 @@
 	
 	dir_entry.signature = 0x2e
-	dir_entry.name = '       '
-	dir_entry.ext = '   '
+	dir_entry.name = b'       '
+	dir_entry.ext = b'   '
 	dir_entry.attr = 0x10
 	
@@ -258,6 +258,6 @@
 	
 	dir_entry.signature = [0x2e, 0x2e]
-	dir_entry.name = '      '
-	dir_entry.ext = '   '
+	dir_entry.name = b'      '
+	dir_entry.ext = b'   '
 	dir_entry.attr = 0x10
 	
Index: tools/mkhord.py
===================================================================
--- tools/mkhord.py	(revision afe1d1e203e5c589222f7579368f84a24d325f3c)
+++ tools/mkhord.py	(revision 432f68a8331e076e5531a65e1516a67ad37318ab)
@@ -84,5 +84,5 @@
 	payload_size_aligned = align_up(payload_size, align)
 	
-	header.tag = "HORD"
+	header.tag = b"HORD"
 	header.version = 1
 	header.encoding = HORD_LSB
Index: tools/mktmpfs.py
===================================================================
--- tools/mktmpfs.py	(revision afe1d1e203e5c589222f7579368f84a24d325f3c)
+++ tools/mktmpfs.py	(revision 432f68a8331e076e5531a65e1516a67ad37318ab)
@@ -80,5 +80,5 @@
 			dentry.kind = TMPFS_FILE
 			dentry.fname_len = len(name)
-			dentry.fname = name
+			dentry.fname = name.encode('ascii')
 			dentry.flen = size
 			
@@ -97,5 +97,5 @@
 			dentry.kind = TMPFS_DIRECTORY
 			dentry.fname_len = len(name)
-			dentry.fname = name
+			dentry.fname = name.encode('ascii')
 			
 			outf.write(dentry.pack())
@@ -122,5 +122,5 @@
 	
 	header = xstruct.create(HEADER)
-	header.tag = "TMPFS"
+	header.tag = b"TMPFS"
 	
 	outf.write(header.pack())