diff --git a/.gitignore b/.gitignore
index ae01ed3..4da2a18 100644
--- a/.gitignore
+++ b/.gitignore
@@ -129,6 +129,7 @@
 /src/t_mmap_write_ro
 /src/t_mmap_writev
 /src/t_mtab
+/src/t_ofd_locks
 /src/t_readdir_1
 /src/t_readdir_2
 /src/t_rename_overwrite
diff --git a/common/rc b/common/rc
index 4ad59b1..a6caca9 100644
--- a/common/rc
+++ b/common/rc
@@ -3308,6 +3308,17 @@ _require_test_fcntl_advisory_locks()
 		_notrun "Require fcntl advisory locks support"
 }
 
+_require_ofd_locks()
+{
+	# Give a test run by getlk wrlck on testfile.
+	# If the running kernel does not support OFD locks,
+	# EINVAL will be returned.
+	_require_test_program "t_ofd_locks"
+	touch $TEST_DIR/ofd_testfile
+	src/t_ofd_locks -t $TEST_DIR/ofd_testfile > /dev/null 2>&1
+	[ $? -eq 22 ] && _notrun "Require OFD locks support"
+}
+
 _require_test_lsattr()
 {
 	testio=$(lsattr -d $TEST_DIR 2>&1)
diff --git a/src/Makefile b/src/Makefile
index 6b9f296..c63c80c 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -15,7 +15,7 @@ TARGETS = dirstress fill fill2 getpagesize holes lstat64 \
 	holetest t_truncate_self t_mmap_dio af_unix t_mmap_stale_pmd \
 	t_mmap_cow_race t_mmap_fallocate fsync-err t_mmap_write_ro \
 	t_ext4_dax_journal_corruption t_ext4_dax_inline_corruption \
-	fsnotify_stress
+	fsnotify_stress t_ofd_locks
 
 LINUX_TARGETS = xfsctl bstat t_mtab getdevicesize preallo_rw_pattern_reader \
 	preallo_rw_pattern_writer ftrunc trunc fs_perms testx looptest \
diff --git a/src/t_ofd_locks.c b/src/t_ofd_locks.c
new file mode 100644
index 0000000..fa5ccfe
--- /dev/null
+++ b/src/t_ofd_locks.c
@@ -0,0 +1,425 @@
+#ifndef _GNU_SOURCE
+#define _GNU_SOURCE
+#endif
+#include <unistd.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <string.h>
+#include <stdlib.h>
+#include <sched.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <sys/ipc.h>
+#include <sys/sem.h>
+
+/*
+ * In distributions that do not have these macros ready in
+ * glibc-headers, compilation fails. Adding them here to avoid
+ * build errors, relevant tests would fail at the helper which
+ * requires OFD locks support and notrun if the kernel does not
+ * support OFD locks. If the kernel does support OFD locks,
+ * we are good to go.
+ *
+ */
+#ifndef F_OFD_GETLK
+#define F_OFD_GETLK    36
+#endif
+
+#ifndef F_OFD_SETLK
+#define F_OFD_SETLK    37
+#endif
+
+#ifndef F_OFD_SETLKW
+#define F_OFD_SETLKW   38
+#endif
+
+/*
+ * Usually we run getlk routine after running setlk routine
+ * in background. However, getlk could be executed before setlk
+ * sometimes, which is invalid for our tests. So we use semaphore
+ * to synchronize between getlk and setlk.
+ *
+ * setlk routine:				 * getlk routine:
+ *						 *
+ *   start					 *   start
+ *     |					 *     |
+ *  open file					 *  open file
+ *     |					 *     |
+ *  init sem					 *     |
+ *     |					 *     |
+ * wait init sem done				 * wait init sem done
+ *     |					 *     |
+ *   setlk					 *     |
+ *     |					 *     |
+ *     |------------clone()--------|		 *     |
+ *     |                           |		 *     |
+ *     |(parent)            (child)|		 *     |
+ *     |                           |		 *     |
+ *     |                      close fd		 *     |
+ *     |                           |		 *     |
+ *     |                     set sem0=0          * wait sem0==0
+ *     |                           |		 *     |
+ *     |                           |		 *   getlk
+ *     |                           |		 *     |
+ *  wait sem1==0                   |    	 *  set sem1=0
+ *     |                           |		 *     |
+ *   wait child                    |    	 *     |
+ *     |                           |		 *  check result
+ *     |                           |		 *     |
+ *    exit                       exit		 *    exit
+ */
+
+/* This is required by semctl to set semaphore value */
+union semun {
+	int              val;    /* Value for SETVAL */
+	struct semid_ds *buf;    /* Buffer for IPC_STAT, IPC_SET */
+	unsigned short  *array;  /* Array for GETALL, SETALL */
+	struct seminfo  *__buf;  /* Buffer for IPC_INFO
+				    (Linux-specific) */
+};
+static int fd;
+static int semid;
+static void err_exit(char *op, int errn)
+{
+	fprintf(stderr, "%s: %s\n", op, strerror(errn));
+	if (fd > 0)
+		close(fd);
+	if (semid > 0 && semctl(semid, 2, IPC_RMID) == -1)
+		perror("exit rmid");
+	exit(errn);
+}
+/*
+ * Flags that used to specify operation details.
+ * They can be specified via command line options.
+ *
+ * option: -P
+ * posix : 1 <--> test posix lock
+ *	   0 <--> test OFD lock (default)
+ *
+ * option: -s/-g
+ * lock_cmd : 1 <--> setlk (default)
+ *	      0 <--> getlk
+ *
+ * option: -r/-w
+ * lock_rw : 1 <--> set/get wrlck (default)
+ *	     0 <--> set/get rdlck
+ *
+ * option: -o num
+ * lock_start : l_start to getlk
+ *
+ * option: -F
+ * clone_fs : clone with CLONE_FILES
+ *
+ * option: -d
+ * use_dup : dup and close to setup condition in setlk
+ *
+ * option: -R/-W
+ * open_rw : 1 <--> open file RDWR (default)
+ *	     0 <--> open file RDONLY
+ *
+ * This option is for _require_ofd_locks helper, just do
+ * fcntl setlk then return errno.
+ * option: -t
+ * testrun : 1 <--> this is a testrun, return after setlk
+ *	     0 <--> this is not a testrun, run as usual
+ *
+ */
+static void usage(char *arg0)
+{
+	printf("Usage: %s [-sgrwo:l:RWPtFd] filename\n", arg0);
+	printf("\t-s/-g : to setlk or to getlk\n");
+	printf("\t-P : POSIX locks\n");
+	printf("\t-F : clone with CLONE_FILES in setlk to setup test condition\n");
+	printf("\t-d : dup and close in setlk\n");
+	printf("\twithout both -F/d, use clone without CLONE_FILES\n");
+	printf("\t-r/-w : set/get rdlck/wrlck\n");
+	printf("\t-o num : offset start to lock, default 0\n");
+	printf("\t-l num : lock length, default 10\n");
+	printf("\t-R/-W : open file RDONLY/RDWR\n\n");
+	printf("\tUsually we run a setlk routine in background and then\n");
+	printf("\trun a getlk routine to check. They must be paired, or\n");
+	printf("\ttest will hang.\n\n");
+	exit(0);
+}
+
+static char child_stack[1048576];
+static int child_fn(void* p)
+{
+	union semun semu;
+	int cfd = *(int *)p;
+	/*
+	 * close relative fd
+	 */
+	if (cfd > 0 && close(cfd) == -1)
+		perror("c-close");
+	/* set sem0 = 0 (setlk and close fd done) */
+	semu.val = 0;
+	if (semctl(semid, 0, SETVAL, semu) == -1)
+		err_exit("set sem0 0", errno);
+	return 0;
+}
+
+int main(int argc, char **argv)
+{
+	int posix = 0;
+	int lock_cmd = 1;
+	int lock_rw = 1;
+	int lock_start = 0;
+	int lock_l = 10;
+	int open_rw = 1;
+	int clone_fs = 0;
+	int use_dup = 0;
+	int testrun = 0;
+	int setlk_macro = F_OFD_SETLKW;
+	int getlk_macro = F_OFD_GETLK;
+	struct timespec ts;
+	key_t semkey;
+	unsigned short vals[2];
+	union semun semu;
+	struct semid_ds sem_ds;
+	struct sembuf sop;
+	int opt, ret, retry;
+
+	while((opt = getopt(argc, argv, "sgrwo:l:PRWtFd")) != -1) {
+		switch(opt) {
+		case 's':
+			lock_cmd = 1;
+			break;
+		case 'g':
+			lock_cmd = 0;
+			break;
+		case 'r':
+			lock_rw = 0;
+			break;
+		case 'w':
+			lock_rw = 1;
+			break;
+		case 'o':
+			lock_start = atoi(optarg);
+			break;
+		case 'l':
+			lock_l = atoi(optarg);
+			break;
+		case 'P':
+			posix = 1;
+			break;
+		case 'R':
+			open_rw = 0;
+			break;
+		case 'W':
+			open_rw = 1;
+			break;
+		case 't':
+			testrun = 1;
+			break;
+		case 'F':
+			clone_fs = 1;
+			break;
+		case 'd':
+			use_dup = 1;
+			break;
+		default:
+			usage(argv[0]);
+			return -1;
+		}
+	}
+	struct flock flk = {
+		.l_whence = SEEK_SET,
+		.l_start = lock_start,
+		.l_len = lock_l,     /* lock range [0,9] */
+		.l_type = F_RDLCK,
+	};
+	if (optind >= argc) {
+		usage(argv[0]);
+		return -1;
+	}
+	if (posix == 0) {
+		flk.l_pid = 0;
+		setlk_macro = F_OFD_SETLKW;
+		getlk_macro = F_OFD_GETLK;
+	} else {
+		setlk_macro = F_SETLKW;
+		getlk_macro = F_GETLK;
+	}
+	if (lock_rw == 1)
+		flk.l_type = F_WRLCK;
+	else
+		flk.l_type = F_RDLCK;
+	if (open_rw == 0)
+		fd = open(argv[optind], O_RDONLY);
+	else
+		fd = open(argv[optind], O_RDWR);
+	if (fd == -1)
+		err_exit("open", errno);
+	/*
+	 * In a testun, we do a fcntl getlk call and exit
+	 * immediately no matter it succeeds or not.
+	 */
+	if (testrun == 1) {
+		fcntl(fd, F_OFD_GETLK, &flk);
+		err_exit("test_ofd_getlk", errno);
+	}
+	if((semkey = ftok(argv[optind], 255)) == -1)
+		err_exit("ftok", errno);
+
+	/* setlk init the semaphore */
+	if (lock_cmd == 1) {
+		/*
+		 * Init the semaphore, with a key related to the
+		 * testfile. getlk routine will wait untill this sem
+		 * has been created and iniialized.
+		 *
+		 * We must make sure the semaphore set is newly created,
+		 * rather then the one left from last run. In which case
+		 * getlk will exit immediately and left setlk routine
+		 * waiting forever. Also because newly created semaphore
+		 * has zero sem_otime, which is used here to sync with
+		 * getlk routine.
+		 */
+		retry = 0;
+		do {
+			semid = semget(semkey, 2, IPC_CREAT|IPC_EXCL);
+			if (semid < 0 && errno == EEXIST) {
+				/* remove sem set after one round of test */
+				if (semctl(semid, 2, IPC_RMID, semu) == -1)
+					err_exit("rmid 0", errno);
+				retry++;
+			} else if (semid < 0)
+				err_exit("semget", errno);
+			else
+				retry = 10;
+		} while (retry < 5);
+		/* We can't create a new semaphore set in 5 tries */
+		if (retry == 5)
+			err_exit("semget", errno);
+		/* Init both new sem to 1 */
+		vals[0] = 1;
+		vals[1] = 1;
+		semu.array = vals;
+		if (semctl(semid, 2, SETALL, semu) == -1)
+			err_exit("init sem", errno);
+		/* Inc both new sem to 2 */
+		sop.sem_num = 0;
+		sop.sem_op = 1;
+		sop.sem_flg = 0;
+		ts.tv_sec = 15;
+		ts.tv_nsec = 0;
+		if (semtimedop(semid, &sop, 1, &ts) == -1)
+			err_exit("inc sem0 2", errno);
+		sop.sem_num = 1;
+		sop.sem_op = 1;
+		sop.sem_flg = 0;
+		ts.tv_sec = 15;
+		ts.tv_nsec = 0;
+		if (semtimedop(semid, &sop, 1, &ts) == -1)
+			err_exit("inc sem1 2", errno);
+		/*
+		 * Wait initialization complete. semctl(2) only update
+		 * sem_ctime, semop(2) will update sem_otime.
+		 */
+		ret = -1;
+		do {
+			memset(&sem_ds, 0, sizeof(sem_ds));
+			semu.buf = &sem_ds;
+			ret = semctl(semid, 0, IPC_STAT, semu);
+		} while (!(ret == 0 && sem_ds.sem_otime != 0));
+		/* place the lock */
+		if (fcntl(fd, setlk_macro, &flk) < 0)
+			err_exit("setlkw", errno);
+	}
+	if (lock_cmd == 1 && use_dup == 1) {
+		/* dup fd and close the newfd */
+		int dfd = dup(fd);
+		if (dfd == -1)
+			err_exit("dup", errno);
+		close(dfd);
+		/* set sem0 = 0 (setlk and close fd done) */
+		semu.val = 0;
+		if (semctl(semid, 0, SETVAL, semu) == -1)
+			err_exit("set sem0 0", errno);
+	}
+	if (lock_cmd == 1 && use_dup == 0) {
+		/*
+		 * clone a child to close the fd then tell getlk to go;
+		 * in parent we keep holding the lock till getlk done.
+		 */
+		pid_t child_pid = 0;
+		if (clone_fs)
+			child_pid = clone(child_fn, child_stack+1048576,
+				CLONE_FILES|CLONE_SYSVSEM|SIGCHLD, &fd);
+		else
+			child_pid = clone(child_fn, child_stack+1048576,
+				CLONE_SYSVSEM|SIGCHLD, &fd);
+		if (child_pid == -1)
+			err_exit("clone", errno);
+		/* wait child done */
+		waitpid(child_pid, NULL, 0);
+	}
+	if (lock_cmd == 1) {
+		/* "hold" lock and wait sem1 == 0 (getlk done) */
+		sop.sem_num = 1;
+		sop.sem_op = 0;
+		sop.sem_flg = 0;
+		ts.tv_sec = 15;
+		ts.tv_nsec = 0;
+		if (semtimedop(semid, &sop, 1, &ts) == -1)
+			err_exit("wait sem1 0", errno);
+		/* remove sem set after one round of test */
+		if (semctl(semid, 2, IPC_RMID, semu) == -1)
+			err_exit("rmid", errno);
+		close(fd);
+		exit(0);
+	}
+	/* getlck */
+	if (lock_cmd == 0) {
+		/* wait sem created and initialized */
+		do {
+			semid = semget(semkey, 2, 0);
+			if (semid != -1)
+				break;
+			if (errno == ENOENT)
+				continue;
+			else
+				err_exit("getlk_semget", errno);
+		} while (1);
+		do {
+			memset(&sem_ds, 0, sizeof(sem_ds));
+			semu.buf = &sem_ds;
+			ret = semctl(semid, 0, IPC_STAT, semu);
+		} while (!(ret == 0 && sem_ds.sem_otime != 0));
+		/* wait sem0 == 0 (setlk and close fd done) */
+		sop.sem_num = 0;
+		sop.sem_op = 0;
+		sop.sem_flg = 0;
+		ts.tv_sec = 15;
+		ts.tv_nsec = 0;
+		if (semtimedop(semid, &sop, 1, &ts) == -1)
+			err_exit("wait sem0 0", errno);
+		if (fcntl(fd, getlk_macro, &flk) < 0)
+			err_exit("getlk", errno);
+		/* set sem1 = 0 (getlk done) */
+		semu.val = 0;
+		if (semctl(semid, 1, SETVAL, semu) == -1)
+			err_exit("set sem1 0", errno);
+		/* check result */
+		switch (flk.l_type) {
+		case F_UNLCK:
+			printf("lock could be placed\n");
+			break;
+		case F_RDLCK:
+			printf("get rdlck\n");
+			break;
+		case F_WRLCK:
+			printf("get wrlck\n");
+			break;
+		default:
+			printf("unknown lock type\n");
+			break;
+		}
+		close(fd);
+	}
+	return 0;
+}
diff --git a/tests/generic/479 b/tests/generic/479
new file mode 100755
index 0000000..bd2bdeb
--- /dev/null
+++ b/tests/generic/479
@@ -0,0 +1,249 @@
+#! /bin/bash
+# FS QA Test 479
+#
+# Test OFD lock. fcntl F_OFD_SETLK to set lock, then F_OFD_GETLK
+# to verify we are being given correct advice by kernel.
+#
+# OFD lock combines POSIX lock and BSD flock:
+#   + does not share between threads
+#   + byte granularity
+#            (both tested by LTP/fcntl3{4,6})
+#   + only release automatically after all open fd closed
+#
+# This test target the third one and expand a little bit.
+#
+# The basic idea is one setlk routine setting locks via fcntl
+# *_SETLK, followed by operations like clone, dup then close fd;
+# another routine getlk getting locks via fcntl *_GETLK.
+#
+# Firstly in setlk routine process P0, place a lock L0 on an
+# opened testfile, then
+#
+#   + clone() a child P1 to close the fd then tell getlk to go,
+#   | parent P0 wait getlk done then close fd.
+# or
+#   + dup() fd to a newfd then close newfd then tell getlk to go,
+#     then wait getlk done then close fd.
+#
+# In getlk process P2, do fcntl *_GETLK with lock L1 after get
+# notified by setlk routine.
+#
+# In the end, getlk routine check the returned struct flock.l_type
+# to see if the lock mechanism works fine.
+#
+# When testing with clone,
+#    + CLONE_FILES set, close releases all locks;
+#    + CLONE_FILES not set, locks remain in P0;
+#
+# If L0 is a POSIX lock,
+#   + it is not inherited into P1
+#   + it is released after dup & close
+#
+# If L0 is a OFD lock,
+#   + it is inherited into P1
+#   + it is not released after dup & close
+#
+#  setlk routine:			 * getlk routine:
+#    start				 *   start
+#      |				 *     |
+#   open file				 *  open file
+#      |				 *     |
+#   init sem				 *     |
+#      |				 *     |
+#  wait init sem done			 * wait init sem done
+#      |				 *     |
+#    setlk L0                            *     |
+#      |				 *     |
+#      |---------clone()--------|	 *     |
+#      |                        |	 *     |
+#      |(child P1)   (parent P0)|	 *     | (P2)
+#      |                        |	 *     |
+#      |                   close fd	 *     |
+#      |                        |	 *     |
+#      |                 set sem0=0	 *  wait sem0==0
+#      |                        |	 *     |
+#      |                        |	 *   getlk L1
+#      |                        |	 *     |
+#   wait sem1==0                |    	 *  set sem1=0
+#      |                        |	 *     |
+#     exit                wait child 	 *     |
+#                               |	 *  check result
+#                           cleanup  	 *     |
+#                               |	 *     |
+#                             exit	 *    exit
+#
+# We can test combainations of:
+#	+ shared or exclusive lock
+#	+ these locks are conflicting or not
+#	+ one OFD lock and one POSIX lock
+#	+ that open testfile RDONLY or RDWR
+#	+ clone with CLONE_FILES or not
+#	+ dup and close newfd
+#
+#-----------------------------------------------------------------------
+# Copyright (c) 2018 Red Hat Inc.  All Rights Reserved.
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License as
+# published by the Free Software Foundation.
+#
+# This program is distributed in the hope that it would be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write the Free Software Foundation,
+# Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+#-----------------------------------------------------------------------
+#
+
+seq=`basename $0`
+seqres=$RESULT_DIR/$seq
+echo "QA output created by $seq"
+
+here=`pwd`
+tmp=/tmp/$$
+status=1	# failure is the default!
+trap "_cleanup; exit \$status" 0 1 2 3 15
+
+_cleanup()
+{
+	cd /
+	rm -f $tmp.*
+}
+
+# get standard environment, filters and checks
+. ./common/rc
+. ./common/filter
+
+# remove previous $seqres.full before test
+rm -f $seqres.full
+
+# Modify as appropriate.
+_supported_fs generic
+_supported_os Linux
+_require_ofd_locks
+
+# real QA test starts here
+# prepare a 4k testfile in TEST_DIR
+$XFS_IO_PROG -f -c "pwrite -S 0xFF 0 4096" \
+	$TEST_DIR/testfile >> $seqres.full 2>&1
+
+do_test()
+{
+	local soptions="$1"
+	local goptions="$2"
+	# print options and getlk output for debug
+	echo $* >> $seqres.full 2>&1
+	# -s : do setlk
+	$here/src/t_ofd_locks $soptions $TEST_DIR/testfile &
+	# -g : do getlk
+	$here/src/t_ofd_locks $goptions $TEST_DIR/testfile | \
+		tee -a $seqres.full
+	wait $!
+
+	# add -F to clone with CLONE_FILES
+	soptions="$1 -F"
+	# with -F, new locks are always file to place
+	$here/src/t_ofd_locks $soptions $TEST_DIR/testfile &
+	$here/src/t_ofd_locks $goptions $TEST_DIR/testfile | \
+		tee -a $seqres.full
+	wait $!
+
+	# add -d to dup and close
+	soptions="$1 -d"
+	$here/src/t_ofd_locks $soptions $TEST_DIR/testfile &
+	$here/src/t_ofd_locks $goptions $TEST_DIR/testfile | \
+		tee -a $seqres.full
+	wait $!
+}
+
+# Always setlk at range [0,9], getlk at range [0,9] [5,24] or [20,29].
+# To open file RDONLY or RDWR should not break the locks.
+# POSIX locks should be released after closed fd, so it wont conflict
+# with other locks in tests
+
+# -P : operate posix lock
+# -w : operate on F_WRLCK
+# -r : operate on F_RDLCK
+# -R : open file RDONLY
+# -W : open file RDWR
+# -o : file offset where the lock starts
+# -l : lock length
+# -F : clone with CLONE_FILES in setlk
+# -d : dup and close in setlk
+
+# setlk wrlck [0,9], getlk wrlck [0,9], expect
+#    + wrlck when CLONE_FILES not set
+#    + unlck when CLONE_FILES set
+#    + wrlck when dup & close
+do_test "-s -w -o 0 -l 10 -W" "-g -w -o 0 -l 10 -W" "wrlck" "unlck" "wrlck"
+# setlk wrlck [0,9], getlk posix wrlck [5,24]
+do_test "-s -w -o 0 -l 10 -W" "-g -w -o 5 -l 20 -W -P" "wrlck" "unlck" "wrlck"
+# setlk wrlck [0,9], getlk wrlck [20,29]
+do_test "-s -w -o 0 -l 10 -W" "-g -w -o 20 -l 10 -W" "unlck" "unlck" "unlck"
+# setlk posix wrlck [0,9], getlk wrlck [5,24]
+do_test "-s -w -o 0 -l 10 -W -P" "-g -w -o 5 -l 20 -W" "wrlck" "unlck" "unlck"
+# setlk posix wrlck [0,9], getlk wrlck [20,29]
+do_test "-s -w -o 0 -l 10 -W -P" "-g -w -o 20 -l 10 -W" "unlck" "unlck" "unlck"
+
+# setlk wrlck [0,9], getlk rdlck [0,9]
+do_test "-s -w -o 0 -l 10 -W" "-g -r -o 0 -l 10 -W" "wrlck" "unlck" "wrlck"
+# setlk wrlck [0,9], getlk posix rdlck [5,24]
+do_test "-s -w -o 0 -l 10" "-g -r -o 5 -l 20 -P" "wrlck" "unlck" "wrlck"
+# setlk wrlck [0,9], getlk rdlck [20,29]
+do_test "-s -w -o 0 -l 10" "-g -r -o 20 -l 10" "unlck" "unlck" "unlck"
+# setlk posix wrlck [0,9], getlk rdlck [5,24]
+do_test "-s -w -o 0 -l 10 -P" "-g -r -o 5 -l 20" "wrlck" "unlck" "unlck"
+# setlk posix wrlck [0,9], getlk rdlck [20,29]
+do_test "-s -w -o 0 -l 10 -P" "-g -r -o 20 -l 10" "unlck" "unlck" "unlck"
+
+# setlk rdlck [0,9], getlk wrlck [0,9], open RDONLY
+do_test "-s -r -o 0 -l 10 -R" "-g -w -o 0 -l 10 -R" "rdlck" "unlck" "rdlck"
+# setlk rdlck [0,9], getlk wrlck [5,24], open RDONLY
+do_test "-s -r -o 0 -l 10 -R" "-g -w -o 5 -l 20 -R -P" "rdlck" "unlck" "rdlck"
+# setlk posix rdlck [0,9], getlk wrlck [5,24], open RDONLY
+do_test "-s -r -o 0 -l 10 -R -P" "-g -w -o 5 -l 20 -R" "rdlck" "unlck" "unlck"
+
+# setlk rdlck [0,9], getlk wrlck [0,9]
+do_test "-s -r -o 0 -l 10" "-g -w -o 0 -l 10" "rdlck" "unlck" "rdlck"
+# setlk rdlck [0,9], getlk posix wrlck [5,24]
+do_test "-s -r -o 0 -l 10" "-g -w -o 5 -l 20 -P" "rdlck" "unlck" "rdlck"
+# setlk posix rdlck [0,9], getlk wrlck [5,24]
+do_test "-s -r -o 0 -l 10 -P" "-g -w -o 5 -l 20" "rdlck" "unlck" "unlck"
+
+# setlk rdlck [0,9], getlk wrlck [20,29], open RDONLY
+do_test "-s -r -o 0 -l 10 -R" "-g -w -o 20 -l 10 -R" "unlck" "unlck" "unlck"
+# setlk posix rdlck [0,9], getlk wrlck [20,29], open RDONLY
+do_test "-s -r -o 0 -l 10 -R -P" "-g -w -o 20 -l 10 -R" "unlck" "unlck" "unlck"
+# setlk rdlck [0,9], getlk wrlck [20,29]
+do_test "-s -r -o 0 -l 10" "-g -w -o 20 -l 10" "unlck" "unlck" "unlck"
+# setlk posix rdlck [0,9], getlk wrlck [20,29]
+do_test "-s -r -o 0 -l 10 -P" "-g -w -o 20 -l 10" "unlck" "unlck" "unlck"
+
+# setlk rdlck [0,9], getlk rdlck [0,9], open RDONLY
+do_test "-s -r -o 0 -l 10 -R" "-g -r -o 0 -l 10 -R" "unlck" "unlck" "unlck"
+# setlk rdlck [0,9], getlk posix rdlck [0,9], open RDONLY
+do_test "-s -r -o 0 -l 10 -R" "-g -r -o 0 -l 10 -R -P" "unlck" "unlck" "unlck"
+# setlk posix rdlck [0,9], getlk rdlck [0,9], open RDONLY
+do_test "-s -r -o 0 -l 10 -R -P" "-g -r -o 0 -l 10 -R" "unlck" "unlck" "unlck"
+# setlk rdlck [0,9], getlk rdlck [0,9]
+do_test "-s -r -o 0 -l 10" "-g -r -o 0 -l 10" "unlck" "unlck" "unlck"
+# setlk posix rdlck [0,9], getlk rdlck [0,9]
+do_test "-s -r -o 0 -l 10 -P" "-g -r -o 0 -l 10" "unlck" "unlck" "unlck"
+
+# setlk rdlck [0,9], getlk rdlck [20,29], open RDONLY
+do_test "-s -r -o 0 -l 10 -R" "-g -r -o 20 -l 10 -R" "unlck" "unlck" "unlck"
+# setlk rdlck [0,9], getlk posix rdlck [20,29], open RDONLY
+do_test "-s -r -o 0 -l 10 -R" "-g -r -o 20 -l 10 -R -P" "unlck" "unlck" "unlck"
+# setlk posix rdlck [0,9], getlk rdlck [20,29], open RDONLY
+do_test "-s -r -o 0 -l 10 -R -P" "-g -r -o 20 -l 10 -R" "unlck" "unlck" "unlck"
+# setlk rdlck [0,9], getlk rdlck [20,29]
+do_test "-s -r -o 0 -l 10" "-g -r -o 20 -l 10" "unlck" "unlck" "unlck"
+# setlk posix rdlck [0,9], getlk rdlck [20,29]
+do_test "-s -r -o 0 -l 10 -P" "-g -r -o 20 -l 10" "unlck" "unlck" "unlck"
+
+# success, all done
+status=0
+exit
diff --git a/tests/generic/479.out b/tests/generic/479.out
new file mode 100644
index 0000000..6381294
--- /dev/null
+++ b/tests/generic/479.out
@@ -0,0 +1,91 @@
+QA output created by 479
+get wrlck
+lock could be placed
+get wrlck
+get wrlck
+lock could be placed
+get wrlck
+lock could be placed
+lock could be placed
+lock could be placed
+get wrlck
+lock could be placed
+lock could be placed
+lock could be placed
+lock could be placed
+lock could be placed
+get wrlck
+lock could be placed
+get wrlck
+get wrlck
+lock could be placed
+get wrlck
+lock could be placed
+lock could be placed
+lock could be placed
+get wrlck
+lock could be placed
+lock could be placed
+lock could be placed
+lock could be placed
+lock could be placed
+get rdlck
+lock could be placed
+get rdlck
+get rdlck
+lock could be placed
+get rdlck
+get rdlck
+lock could be placed
+lock could be placed
+get rdlck
+lock could be placed
+get rdlck
+get rdlck
+lock could be placed
+get rdlck
+get rdlck
+lock could be placed
+lock could be placed
+lock could be placed
+lock could be placed
+lock could be placed
+lock could be placed
+lock could be placed
+lock could be placed
+lock could be placed
+lock could be placed
+lock could be placed
+lock could be placed
+lock could be placed
+lock could be placed
+lock could be placed
+lock could be placed
+lock could be placed
+lock could be placed
+lock could be placed
+lock could be placed
+lock could be placed
+lock could be placed
+lock could be placed
+lock could be placed
+lock could be placed
+lock could be placed
+lock could be placed
+lock could be placed
+lock could be placed
+lock could be placed
+lock could be placed
+lock could be placed
+lock could be placed
+lock could be placed
+lock could be placed
+lock could be placed
+lock could be placed
+lock could be placed
+lock could be placed
+lock could be placed
+lock could be placed
+lock could be placed
+lock could be placed
+lock could be placed
diff --git a/tests/generic/group b/tests/generic/group
index 8416957..a578696 100644
--- a/tests/generic/group
+++ b/tests/generic/group
@@ -481,3 +481,4 @@
 476 auto rw
 477 auto quick exportfs
 478 auto stress dangerous fsnotify
+479 auto quick
