Check Skiboot NVRAM options before testcase

Skiboot parses configuration options in NVRAM at boot time which affect
runtime behaviour, and several of these can be potentially dangerous or
detrimental. When possible check NVRAM for any Skiboot configuration
options and warn about them and the end of the test run.

Fixes #492

Example:
2019-05-10 13:42:57,768:op-test.common.OpTestUtil:dump_nvram_opts:WARNING:
2 NVRAM debugging options set
These may adversely affect test results; verify these are appropriate if a failure occurs:
----------------------------------------------------------
bootargs=modprobe.blacklist=amdgpu
test-cfg=test-value
----------------------------------------------------------

Signed-off-by: Samuel Mendoza-Jonas <[email protected]>

Author: sammj

OpTestConfiguration.py

@@ -372,6 +372,7 @@ def __init__(self):
         self.util_bmc_server = None # OpenBMC REST Server
         atexit.register(self.__del__) # allows cleanup handler to run (OpExit)
         self.firmware_versions = None
+        self.nvram_debug_opts = None
 
         for dir in (os.walk(os.path.join(self.basedir, 'addons')).next()[1]):
             optAddons[dir] = importlib.import_module("addons." + dir + ".OpTest" + dir + "Setup")

common/OpTestSystem.py

@@ -378,6 +378,11 @@ def goto_state(self, state):
                          message=("OpTestSystem something set the system to UNKNOWN,"
                            " check the logs for details, we will be stopping the system"))
 
+        # If we haven't checked for dangerous NVRAM options yet and
+        # checking won't disrupt the test, do so now.
+        if self.conf.nvram_debug_opts is None and state in [OpSystemState.PETITBOOT_SHELL, OpSystemState.OS]:
+            self.util.check_nvram_options(self.console)
+
     def run_DETECT(self, target_state):
         self.detect_counter += 1
         detect_state = OpSystemState.UNKNOWN

common/OpTestUtil.py

@@ -284,6 +284,7 @@ def cleanup(self):
         if self.conf.dump:
           self.conf.dump = False # possible for multiple passes here
           self.dump_versions()
+          self.dump_nvram_opts()
 
         # leave closing the qemu scratch disk until last
         # no known reasons at this point, document in future
@@ -313,6 +314,33 @@ def dump_versions(self):
             else ('\n'.join(f for f in self.conf.firmware_versions)))
             ))
 
+    def check_nvram_options(self, console):
+        try:
+            console.run_command("which nvram")
+        except:
+            log.info("No NVRAM utility available to check options")
+            return
+
+        result = console.run_command("nvram -p ibm,skiboot --print-config")
+        self.conf.nvram_debug_opts = [o for o in result if "=" in o]
+
+        if len(self.conf.nvram_debug_opts) == 0:
+            log.info("No NVRAM debugging options set")
+            return
+
+        log.warning("{} NVRAM debugging options set".format(len(self.conf.nvram_debug_opts)))
+
+    def dump_nvram_opts(self):
+        if self.conf.nvram_debug_opts is None or len(self.conf.nvram_debug_opts) == 0:
+            return
+
+        log.warning("\n{} NVRAM debugging options set\n"
+                "These may adversely affect test results; verify these are appropriate if a failure occurs:\n"
+                 "----------------------------------------------------------\n"
+                 "{}\n"
+                 "----------------------------------------------------------\n"
+            .format(len(self.conf.nvram_debug_opts), '\n'.join(f for f in self.conf.nvram_debug_opts)))
+
     def build_proxy(self, proxy, no_proxy_ips):
         if no_proxy_ips is None:
           return proxy