tests/acceptance: Fix race conditions in s390x tests & skip fedora on gitlab-CI

There was a race condition in the first test where there was already the
"crw" output in the dmesg, but the "0.0.4711" entry has not been created
in the /sys fs yet. Fix it by waiting until it is there.

The second test has even more problems on gitlab-CI. Even after adding some
more synchronization points (that wait for some messages in the "dmesg"
output to make sure that the modules got loaded correctly), there are still
occasionally some hangs in this test when it is running in the gitlab-CI.
So far I was unable to reproduce these hangs locally on my computer, so
this issue might take a while to debug. Thus disable the 2nd test in the
gitlab-CI until the problems are better understood and fixed.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Tested-by: Willian Rampazzo <willianr@redhat.com>
Reviewed-by: Willian Rampazzo <willianr@redhat.com>
Message-Id: <20210108185645.86351-1-thuth@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>

tests/acceptance/machine_s390_ccw_virtio.py

@@ -12,6 +12,7 @@
 import os
 import tempfile
 
+from avocado import skipIf
 from avocado_qemu import Test
 from avocado_qemu import exec_command_and_wait_for_pattern
 from avocado_qemu import wait_for_console_pattern
@@ -133,8 +134,10 @@ def test_s390x_devices(self):
         self.vm.command('device_add', driver='virtio-net-ccw',
                         devno='fe.0.4711', id='net_4711')
         self.wait_for_crw_reports()
-        exec_command_and_wait_for_pattern(self, 'ls /sys/bus/ccw/devices/',
-                                          '0.0.4711')
+        exec_command_and_wait_for_pattern(self, 'for i in 1 2 3 4 5 6 7 ; do '
+                    'if [ -e /sys/bus/ccw/devices/*4711 ]; then break; fi ;'
+                    'sleep 1 ; done ; ls /sys/bus/ccw/devices/',
+                    '0.0.4711')
         # and detach it again
         self.clear_guest_dmesg()
         self.vm.command('device_del', id='net_4711')
@@ -155,6 +158,7 @@ def test_s390x_devices(self):
                                           'MemTotal:         115640 kB')
 
 
+    @skipIf(os.getenv('GITLAB_CI'), 'Running on GitLab')
     def test_s390x_fedora(self):
 
         """
@@ -199,6 +203,9 @@ def test_s390x_fedora(self):
 
         # Some tests to see whether the CLI options have been considered:
         self.log.info("Test whether QEMU CLI options have been considered")
+        exec_command_and_wait_for_pattern(self,
+                        'while ! (dmesg | grep enP7p0s0) ; do sleep 1 ; done',
+                        'virtio_net virtio0 enP7p0s0: renamed')
         exec_command_and_wait_for_pattern(self, 'lspci',
                              '0007:00:00.0 Class 0200: Device 1af4:1000')
         exec_command_and_wait_for_pattern(self,
@@ -222,6 +229,9 @@ def test_s390x_fedora(self):
         # can simply read the written "magic bytes" back from the PPM file to
         # check whether the framebuffer is working as expected.
         self.log.info("Test screendump of virtio-gpu device")
+        exec_command_and_wait_for_pattern(self,
+                        'while ! (dmesg | grep gpudrmfb) ; do sleep 1 ; done',
+                        'virtio_gpudrmfb frame buffer device')
         exec_command_and_wait_for_pattern(self,
             'echo -e "\e[?25l" > /dev/tty0', ':/#')
         exec_command_and_wait_for_pattern(self, 'for ((i=0;i<250;i++)); do '