qemu.tests.multi_disk_random_hotplug: Check for I/O Errors

Check for I/O Errors before the test end and raise Warning in such case.
Signed-off-by: NLukáš Doktor <ldoktor@redhat.com>

qemu/tests/multi_disk_random_hotplug.py

@@ -460,4 +460,11 @@ def run(test, params, env):
             utils_test.run_virt_sub_test(test, params, env, sub_type)
 
     # Check for various KVM failures
+    error.context("Validating VM after all disk hotplug/unplugs",
+                  logging.debug)
     vm.verify_alive()
+    out = session.cmd_output('dmesg')
+    if "I/O error" in out:
+        logging.warn(out)
+        raise error.TestWarn("I/O error messages occured in dmesg, check"
+                             "the log for details.")