zdtm: add 'nolazy' flag for tests not compatible with lazy pages

The kernel support for lazy pages (userfaultfd) lacks many important
features which effectively prevents success in certain tests.
Allow skipping such test with somewhat informative message

travis-ci: success for lazy-pages: improve testability (rev2)
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

test/zdtm.py

@@ -1697,6 +1697,11 @@ def run_tests(opts):
 					l.skip(t, "samens test in the same namespace")
 					continue
 
+			if opts['lazy_pages']:
+				if test_flag(tdesc, 'nolazy'):
+					l.skip(t, "lazy pages are not supported")
+					continue
+
 			test_flavs = tdesc.get('flavor', 'h ns uns').split()
 			opts_flavs = (opts['flavor'] or 'h,ns,uns').split(',')
 			if opts_flavs != ['best']:

test/zdtm/static/cow00.desc

 # /proc/pid/pagemap doesn't show phys addr for unprivileged users
-{'flavor': 'ns h', 'flags': 'suid'}
+{'flavor': 'ns h', 'flags': 'suid nolazy'}

test/zdtm/static/cow01.desc

-{'flavor': 'h ns', 'flags': 'suid'}
+{'flavor': 'h ns', 'flags': 'suid nolazy'}

test/zdtm/transition/fork.desc

+{'flags' : 'nolazy'}

test/zdtm/transition/fork2.desc

+{'flags' : 'nolazy'}