tests: Use pgrep instead of ps

The ps command as shipped by busybox does not support the "command"
column. Change the code to use pgrep instead which will work fine in all
environments.

In addition, raise an exception if PID was not found since the test
would just hang with pid = 0.

Signed-off-by: Benjamin Berg <benjamin.berg@intel.com>

tests/hwsim/test_ap_eap.py

@@ -7607,20 +7607,15 @@ def test_ap_wpa2_eap_psk_mac_addr_change(dev, apdev):
     params = hostapd.wpa2_eap_params(ssid="test-wpa2-eap")
     hapd = hostapd.add_ap(apdev[0], params)
 
-    cmd = subprocess.Popen(['ps', '-eo', 'pid,command'], stdout=subprocess.PIPE)
-    res = cmd.stdout.read().decode()
+    cmd = subprocess.Popen(['pgrep', '-nf', 'wpa_supplicant.*' + dev[0].ifname],
+                           stdout=subprocess.PIPE)
+    res = cmd.stdout.read().decode().strip()
     cmd.stdout.close()
-    pid = 0
-    for p in res.splitlines():
-        if "wpa_supplicant" not in p:
-            continue
-        if dev[0].ifname not in p:
-            continue
-        pid = int(p.strip().split(' ')[0])
-    if pid == 0:
-        logger.info("Could not find wpa_supplicant PID")
-    else:
+    if res:
+        pid = int(res)
         logger.info("wpa_supplicant PID %d" % pid)
+    else:
+        raise Exception("Could not find wpa_supplicant PID")
 
     addr = dev[0].get_status_field("address")
     subprocess.call(['ip', 'link', 'set', 'dev', dev[0].ifname, 'down'])

tests/hwsim/vm/inside.sh

@@ -146,6 +146,9 @@ if [ "$TELNET" = "1" ] ; then
   ) &
 fi
 
+# procps 3.3.17 needs an uptime of >1s (relevant for UML time-travel)
+sleep 1
+
 # check if we're rebooting due to a kernel panic ...
 if grep -q 'Kernel panic' /tmp/logs/console ; then
 	echo "KERNEL CRASHED!" >/dev/ttyS0