Index: lib/libc/net/getaddrinfo.c
diff -u lib/libc/net/getaddrinfo.c.orig lib/libc/net/getaddrinfo.c
--- lib/libc/net/getaddrinfo.c.orig	Mon Sep 16 05:36:38 2002
+++ lib/libc/net/getaddrinfo.c	Wed Oct  2 00:54:27 2002
@@ -274,6 +274,15 @@
 	"Unknown error", 				/* EAI_MAX        */
 };
 
+/* Make getaddrinfo thread-safe in libc for use with kernel threads. */
+#include "libc_private.h"
+#include "spinlock.h"
+spinlock_t _getaddrinfo_thread_lock = _SPINLOCK_INITIALIZER;
+#define THREAD_LOCK() \
+	if (__isthreaded) _SPINLOCK(&_getaddrinfo_thread_lock);
+#define THREAD_UNLOCK() \
+	if (__isthreaded) _SPINUNLOCK(&_getaddrinfo_thread_lock);
+
 /* XXX macros that make external reference is BAD. */
 
 #define	GET_AI(ai, afd, addr) \
@@ -599,11 +608,15 @@
 
 	result = NULL;
 
+	THREAD_LOCK();
+
 	/*
 	 * if the servname does not match socktype/protocol, ignore it.
 	 */
-	if (get_portmatch(pai, servname) != 0)
+	if (get_portmatch(pai, servname) != 0) {
+		THREAD_UNLOCK();
 		return 0;
+	}
 
 	switch (nsdispatch(&result, dtab, NSDB_HOSTS, "getaddrinfo",
 			default_dns_files, hostname, pai)) {
@@ -624,12 +637,14 @@
 		}
 		break;
 	}
+	THREAD_UNLOCK();
 
 	*res = result;
 
 	return 0;
 
 free:
+	THREAD_UNLOCK();
 	if (result)
 		freeaddrinfo(result);
 	return error;
Index: lib/libc/net/name6.c
diff -u lib/libc/net/name6.c.orig lib/libc/net/name6.c
--- lib/libc/net/name6.c.orig	Tue Sep 24 18:23:28 2002
+++ lib/libc/net/name6.c	Wed Oct  2 00:55:24 2002
@@ -191,6 +191,15 @@
 static int	 _icmp_ghbyaddr(void *, void *, va_list);
 #endif /* ICMPNL */
 
+/* Make getipnodeby*() thread-safe in libc for use with kernel threads. */
+#include "libc_private.h"
+#include "spinlock.h"
+extern spinlock_t _getaddrinfo_thread_lock;
+#define THREAD_LOCK() \
+	if (__isthreaded) _SPINLOCK(&_getaddrinfo_thread_lock);
+#define THREAD_UNLOCK() \
+	if (__isthreaded) _SPINUNLOCK(&_getaddrinfo_thread_lock);
+
 /* Host lookup order if nsswitch.conf is broken or nonexistant */
 static const ns_src default_src[] = { 
 	{ NSSRC_FILES, NS_SUCCESS },
@@ -277,8 +286,10 @@
 		}
 	}
 
+	THREAD_LOCK();
 	rval = nsdispatch(&hp, dtab, NSDB_HOSTS, "ghbyname", default_src,
 			  name, af, errp);
+	THREAD_UNLOCK();
 	return (rval == NS_SUCCESS) ? hp : NULL;
 }
 
@@ -422,8 +433,10 @@
 		return NULL;
 	}
 
+	THREAD_LOCK();
 	rval = nsdispatch(&hp, dtab, NSDB_HOSTS, "ghbyaddr", default_src,
 			  src, len, af, errp);
+	THREAD_UNLOCK();
 	return (rval == NS_SUCCESS) ? hp : NULL;
 }