zdtm: check /proc/sys/kernel/taint and fail if it is non-zero

We don't want to run tests, if a kernel has a problem. And we want
to know when the taint flag is changed.
Signed-off-by: Andrei Vagin <avagin@virtuozzo.com>
Acked-by: Pavel Emelyanov <xemul@virtuozzo.com>
Signed-off-by: Andrei Vagin <avagin@virtuozzo.com>

test/zdtm.py

@@ -1389,6 +1389,11 @@ class launcher:
 			print >> self.__file_report, "# Timestamp: " + now.strftime("%Y-%m-%d %H:%M") + " (GMT+1)"
 			print >> self.__file_report, "# "
 			print >> self.__file_report, "1.." + str(nr_tests)
+		self.__taint = open("/proc/sys/kernel/tainted").read()
+		if int(self.__taint, 0) != 0:
+			print "The kernel is tainted: %r" % self.__taint
+			if not opts["ignore_taint"]:
+				raise Exception("The kernel is tainted: %r" % self.__taint)
 
 	def __show_progress(self, msg):
 		perc = self.__nr * 16 / self.__total
@@ -1408,6 +1413,10 @@ class launcher:
 		if len(self.__subs) >= self.__max:
 			self.wait()
 
+		taint = open("/proc/sys/kernel/tainted").read()
+		if self.__taint != taint:
+			raise Exception("The kernel is tainted: %r (%r)" % (taint, self.__taint))
+
 		if test_flag(desc, 'excl'):
 			self.wait_all()
 
@@ -1911,6 +1920,7 @@ rp.add_argument("-k", "--keep-img", help = "Whether or not to keep images after
 		choices = ['always', 'never', 'failed'], default = 'failed')
 rp.add_argument("--report", help = "Generate summary report in directory")
 rp.add_argument("--keep-going", help = "Keep running tests in spite of failures", action = 'store_true')
+rp.add_argument("--ignore-taint", help = "Don't care about a non-zero kernel taint flag", action = 'store_true')
 
 lp = sp.add_parser("list", help = "List tests")
 lp.set_defaults(action = list_tests)