Hi all, this is a test failure posted by Nikita Yushchenko [1]. LTP NFS test nfslock01 looks to be failing on NFS v3: "not unsharing /var makes AF_UNIX socket for host's rpcbind to become available inside ltpns. Then, at nfs3 mount time, kernel creates an instance of lockd for ltpns, and ports for that instance leak to host's rpcbind and overwrite ports for lockd already active for root namespace. This breaks nfs3 file locking." This error has been hidden, showing only with extra patch from Nikita [2]. Because the patch has not been merged, in case you want to verify yourself, feel free to use my LTP fork branch nfs_flock/fail-on-error to get this patch + strace debugging [3]: # PATH="/opt/ltp/testcases/bin:$PATH" /opt/ltp/testcases/bin/nfslock01 -t tcp -v 3 ... nfslock01 1 TINFO: initialize 'lhost' 'ltp_ns_veth2' interface nfslock01 1 TINFO: add local addr 10.0.0.2/24 nfslock01 1 TINFO: add local addr fd00:1:1:1::2/64 nfslock01 1 TINFO: initialize 'rhost' 'ltp_ns_veth1' interface nfslock01 1 TINFO: add remote addr 10.0.0.1/24 nfslock01 1 TINFO: add remote addr fd00:1:1:1::1/64 nfslock01 1 TINFO: Network config (local -- remote): nfslock01 1 TINFO: ltp_ns_veth2 -- ltp_ns_veth1 nfslock01 1 TINFO: 10.0.0.2/24 -- 10.0.0.1/24 nfslock01 1 TINFO: fd00:1:1:1::2/64 -- fd00:1:1:1::1/64 nfslock01 1 TINFO: timeout per run is 0h 5m 0s nfslock01 1 TINFO: setup NFSv3, socket type tcp nfslock01 1 TINFO: Mounting NFS: mount -v -t nfs -o proto=tcp,vers=3 10.0.0.2:/tmp/LTP_nfslock01.PAYCDFih75/3/tcp /tmp/LTP_nfslock01.PAYCDFih75/3/0 nfslock01 1 TINFO: creating test files nfslock01 1 TINFO: Testing locking nfslock01 1 TINFO: locking 'flock_idata' file and writing data nfslock01 1 TINFO: waiting for pids: 2022 2023 execve("/opt/ltp/testcases/bin/nfs_flock", ["nfs_flock", "0", "flock_idata"], 0x7ffd4dae5880 /* 206 vars */execve("/opt/ltp/testcases/bin/nfs_flock", ["nfs_flock", "1", "flock_idata"], 0x7ffee8d52690 /* 206 vars */) = 0 brk(NULL) = 0x555ad67cc000 ... openat(AT_FDCWD, "flock_idata", O_RDWR) = 3 ) = 3 fcntl(3, F_SETLKW, {l_type=F_WRLCK, l_whence=SEEK_SET, l_start=64, l_len=64}fcntl(3, F_SETLKW, {l_type=F_WRLCK, l_whence=SEEK_SET, l_start=0, l_len=64}) = -1 ENOLCK (No locks available) newfstatat(1, "", {st_mode=S_IFCHR|0600, st_rdev=makedev(0x88, 0x1), ...}, AT_EMPTY_PATH) = 0 brk(NULL) = 0x55aefc2d5000 brk(0x55aefc2f6000) = 0x55aefc2f6000 write(1, "failed in writeb_lock, Errno = 3"..., 34failed in writeb_lock, Errno = 37 ) = 34 exit_group(1) = ? +++ exited with 1 +++ ) = -1 ENOLCK (No locks available) newfstatat(1, "", {st_mode=S_IFCHR|0600, st_rdev=makedev(0x88, 0x1), ...}, AT_EMPTY_PATH) = 0 brk(NULL) = 0x555ad67cc000 brk(0x555ad67ed000) = 0x555ad67ed000 write(1, "failed in writeb_lock, Errno = 3"..., 34failed in writeb_lock, Errno = 37 ) = 34 exit_group(1) = ? +++ exited with 1 +++ nfslock01 1 TFAIL: nfs_lock process failed ... Dmesg shows: "lockd: cannot monitor 10.0.0.2", test fails on fcntl(fd, F_SETLKW, &lock), lock.l_whence is SEEK_SET. Running other NFS versions (-v 4 or -v 4.1 or -v 4.2) works ok. Also tested only on TCP due UDP being recently disabled by default. I found this behaviour on various kernels (openSUSE 5.16, Debian: 5.16, 5.10, SLES 5.14 and 5.3 - both heavily patched). Is it a bug in lockd or in a test? Is there some limitation on v3? Kind regards, Petr