[LTP] [RFC??[DO_NOT_MERGE][PATCH v2 1/1] netstress: Fix race between SETSID() and exit(0)

[Cyril Hrubis]

Hi!
Uff, I did found the root cause after debugging for a while.

The network tests rely a lot on passing data between processes by files
by a local directory and .needs_checkpoints causes the test to run under
a different directory, that is because checkpoints needs a backing file
that is mapped into the process memory. And so after setting
.need_checkpoints the client was storing the file into a different
directory.

This should be a minimal fix:

diff --git a/testcases/lib/tst_net.sh b/testcases/lib/tst_net.sh
index 047686dc3..891472c8a 100644
--- a/testcases/lib/tst_net.sh
+++ b/testcases/lib/tst_net.sh
@@ -715,7 +715,7 @@ tst_netload()
        fi

        s_opts="${cs_opts}${s_opts}-R $s_replies -B $TST_TMPDIR"
-       c_opts="${cs_opts}${c_opts}-a $c_num -r $((c_requests / run_cnt)) -d $rfile"
+       c_opts="${cs_opts}${c_opts}-a $c_num -r $((c_requests / run_cnt)) -d $PWD/$rfile"

        tst_res_ TINFO "run server 'netstress $s_opts'"
        tst_res_ TINFO "run client 'netstress -l $c_opts' $run_cnt times"



However the debugging took longer than I wanted to since the network
tests are such a mess. The server does exit by TBROK (which looks like
it's an expected behavior), only half of the sever log is printed on a
failure, etc. These should really deserve some cleanups...

-- 
Cyril Hrubis
chrubis@suse.cz