[CRIU] A few network related tests are failing

[Adrian Reber]

On one of my test systems some network related tests are failing:

# ./zdtm.py run -t zdtm/static/socket-tcp6-closed -t zdtm/static/socket-tcp4v6-closed -t zdtm/static/socket-tcp-syn-sent -t zdtm/static/netns-nf --keep-going

All of those tests either fail with something like:

tail: cannot open 'zdtm/static/socket-tcp6-closed.out' for reading: No such file or directory

or:

./netns-nf --pidfile=netns-nf.pid --outfile=netns-nf.out --filename=netns-nf.test
The test failed (0, 1)
make: *** [Makefile:385: netns-nf.pid] Error 1
 Test zdtm/static/netns-nf FAIL at ['make', '--no-print-directory', '-C', 'zdtm/static', 'netns-nf.pid'] 
Test output: ================================
iptables v1.6.2: can't initialize iptables table `filter': Table does not exist (do you need to insmod?)
Perhaps iptables or your kernel needs to be upgraded.
16:21:51.941:     4: ERR: netns-nf.c:21: Can't set input rule (errno = 2 (No such file or directory))
16:21:51.941:     3: ERR: test.c:316: Test exited unexpectedly with code 255

All of those tests can fail with the iptables error or
with the tail error. I think this is not a real test
error but maybe timing related or something like that.

It is on a 4.18 kernel and all other tests in zdtm are working.

Any recommendations how to fix this. Where to look?

		Adrian