diff --git a/libc/dns/include/resolv_private.h b/libc/dns/include/resolv_private.h
index 4a832d0..0dab3d8 100644
--- a/libc/dns/include/resolv_private.h
+++ b/libc/dns/include/resolv_private.h
@@ -63,6 +63,13 @@
 /* Despite this file's name, it's part of libresolv. On Android, that means it's part of libc :-( */
 #pragma GCC visibility push(default)
 
+// Linux defines MAXHOSTNAMELEN as 64, while the domain name limit in
+// RFC 1034 and RFC 1035 is 255 octets.
+#ifdef MAXHOSTNAMELEN
+#undef MAXHOSTNAMELEN
+#endif
+#define MAXHOSTNAMELEN 256
+
 /*
  * Revision information.  This is the release date in YYYYMMDD format.
  * It can change every day so the right thing to do with it is use it
diff --git a/libc/include/netdb.h b/libc/include/netdb.h
index e165376..3bb973c 100644
--- a/libc/include/netdb.h
+++ b/libc/include/netdb.h
@@ -73,9 +73,6 @@
 #define	_PATH_PROTOCOLS	"/system/etc/protocols"
 #define	_PATH_SERVICES	"/system/etc/services"
 
-#define  MAXHOSTNAMELEN  256
-
-
 /*
  * Structures returned by network data base library.  All addresses are
  * supplied in host order, and returned in network order (suitable for
diff --git a/libc/include/sys/param.h b/libc/include/sys/param.h
index 03a462e..e64d6ce 100644
--- a/libc/include/sys/param.h
+++ b/libc/include/sys/param.h
@@ -29,8 +29,8 @@
 #define _SYS_PARAM_H_
 
 #include <limits.h>
+#include <linux/param.h>
 
-#define HZ 100
 #define MAXPATHLEN  PATH_MAX
 #define MAXSYMLINKS 8
 
diff --git a/libc/kernel/tools/defaults.py b/libc/kernel/tools/defaults.py
index 2efd455..8aba998 100644
--- a/libc/kernel/tools/defaults.py
+++ b/libc/kernel/tools/defaults.py
@@ -118,10 +118,8 @@
 # the generated files.
 #
 kernel_ignored_macros = set(
-        [ "MAXHOSTNAMELEN",  # for some reason, Linux defines it to 64
-                             # while most of the BSD code expects this to be 256
-                             # so ignore the kernel-provided definition and
-                             # define it in the Bionic headers instead
+        [
+
         ]
     )
 
diff --git a/libc/kernel/uapi/asm-generic/param.h b/libc/kernel/uapi/asm-generic/param.h
index aa21864..6bde154 100644
--- a/libc/kernel/uapi/asm-generic/param.h
+++ b/libc/kernel/uapi/asm-generic/param.h
@@ -29,5 +29,6 @@
 #ifndef NOGROUP
 #define NOGROUP (- 1)
 #endif
-#endif
+#define MAXHOSTNAMELEN 64
 /* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
+#endif