diff --git a/Makefile.inc1 b/Makefile.inc1
index 0c270e9639e2..f9980634115b 100644
--- a/Makefile.inc1
+++ b/Makefile.inc1
@@ -522,7 +522,7 @@ distributeworld installworld: installcheck
 	mkdir -p ${INSTALLTMP}
 	for prog in [ awk cap_mkdb cat chflags chmod chown \
 	    date echo egrep find grep install-info \
-	    ln make mkdir mtree mv pwd_mkdb rm sed sh sysctl \
+	    ln lockf make mkdir mtree mv pwd_mkdb rm sed sh sysctl \
 	    test true uname wc zic; do \
 		cp `which $$prog` ${INSTALLTMP}; \
 	done
diff --git a/share/mk/bsd.info.mk b/share/mk/bsd.info.mk
index 717007d9c8f8..1de6cf7a1dd3 100644
--- a/share/mk/bsd.info.mk
+++ b/share/mk/bsd.info.mk
@@ -145,6 +145,7 @@ ${x:S/$/${ICOMPRESS_EXT}/}:	${x}
 .for x in ${INFO}
 INSTALLINFODIRS+= ${x:S/$/-install/}
 ${x:S/$/-install/}:
+	lockf -k ${DESTDIR}${INFODIR}/${INFODIRFILE} \
 	${INSTALLINFO} ${INSTALLINFOFLAGS} \
 	    --defsection=${INFOSECTION} \
 	    --defentry=${INFOENTRY_${x}} \