diff --git a/configure.ac b/configure.ac
index aa7bef4..ca8adc5 100644
--- a/configure.ac
+++ b/configure.ac
@@ -18,6 +18,7 @@
 LTP_CHECK_SYSCALL_EVENTFD
 LTP_CHECK_SYSCALL_MODIFY_LDT
 LTP_CHECK_SYSCALL_SIGNALFD
+LTP_CHECK_SYSCALL_UNSHARE
 LTP_CHECK_SELINUX
 LTP_CHECK_CRYPTO
 LTP_CHECK_TASKSTATS