diff --git a/lnet/autoconf/lustre-lnet.m4 b/lnet/autoconf/lustre-lnet.m4
index c7f71601aa326d9254cd887bd69ae0092fc72b87..c016f84086342808dda91722922558103381cfc0 100644
--- a/lnet/autoconf/lustre-lnet.m4
+++ b/lnet/autoconf/lustre-lnet.m4
@@ -1056,6 +1056,29 @@ AC_DEFINE(HAVE_SHOW_TASK, 1, [show_task is exported])
 ])
 ])
 
+# check userland __u64 type
+AC_DEFUN([LN_U64_LONG_LONG],
+[AC_MSG_CHECKING([check u64 is long long type])
+tmp_flags="$CFLAGS"
+CFLAGS="$CFLAGS -Werror"
+AC_COMPILE_IFELSE([
+	#include <asm/types.h>
+	int main(void) {
+		unsigned long long *data1;
+		__u64 *data2;
+		
+		data1 = data2;
+		return 0;
+	}
+],[
+	AC_MSG_RESULT([yes])
+        AC_DEFINE(HAVE_U64_LONG_LONG, 1,
+                  [__u64 is long long type])
+],[
+])
+CFLAGS="$tmp_flags"
+])
+
 # LN_TASKLIST_LOCK
 # 2.6.18 remove tasklist_lock export
 AC_DEFUN([LN_TASKLIST_LOCK],
@@ -1205,6 +1228,7 @@ LN_CONFIG_MX
 LN_STRUCT_PAGE_LIST
 LN_STRUCT_SIGHAND
 LN_FUNC_SHOW_TASK
+LN_U64_LONG_LONG
 # 2.6.18
 LN_TASKLIST_LOCK
 # 2.6.19
diff --git a/lnet/include/libcfs/linux/kp30.h b/lnet/include/libcfs/linux/kp30.h
index aceaa2c0ea34e9da21d778ca961306203d7d9d4a..7de45d6ee7eb4db1c53b54db837ecd896ff3289a 100644
--- a/lnet/include/libcfs/linux/kp30.h
+++ b/lnet/include/libcfs/linux/kp30.h
@@ -340,7 +340,7 @@ extern int  lwt_snapshot (cycles_t *now, int *ncpu, int *total_size,
  #define _LWORDSIZE __WORDSIZE
 #endif
 
-#if (defined(__x86_64__) && (defined(__KERNEL__) || defined(CRAY_XT3)))
+#if (defined(__x86_64__) && (defined(__KERNEL__) || defined(CRAY_XT3))) || defined(HAVE_U64_LONG_LONG)
 /* x86_64 defines __u64 as "long" in userspace, but "long long" in the kernel */
 # define LPU64 "%Lu"
 # define LPD64 "%Ld"