From b630bb95058052bc10b1c7fb9f1d2bcb5b28b49d Mon Sep 17 00:00:00 2001
From: Sage Weil <sage@redhat.com>
Date: Thu, 31 Oct 2019 10:42:53 -0500
Subject: [PATCH] mgr/ActivePyModules: behave if a module queries a devid that
 does not exist

The GIL reacquire was being handled in the lambda, but that was not
getting called if the device didn't exist, leading to a crash.

Add a trivial CLI test.

Fixes: https://tracker.ceph.com/issues/42578
Signed-off-by: Sage Weil <sage@redhat.com>
(cherry picked from commit 67e5139b02518cbc83e5156e2f74a5d22f4d97a4)
---
 qa/workunits/cephtool/test.sh |  8 ++++++++
 src/mgr/ActivePyModules.cc    | 13 +++++++++----
 2 files changed, 17 insertions(+), 4 deletions(-)

diff --git a/qa/workunits/cephtool/test.sh b/qa/workunits/cephtool/test.sh
index 55ea6c894e49..a4bd3d415a6f 100755
--- a/qa/workunits/cephtool/test.sh
+++ b/qa/workunits/cephtool/test.sh
@@ -2705,6 +2705,13 @@ function test_mgr_tell()
   ceph tell mgr osd status
 }
 
+function test_mgr_devices()
+{
+  ceph device ls
+  expect_false ceph device info doesnotexist
+  expect_false ceph device get-health-metrics doesnotexist
+}
+
 function test_per_pool_scrub_status()
 {
   ceph osd pool create noscrub_pool 12
@@ -2807,6 +2814,7 @@ MDS_TESTS+=" mon_mds_metadata"
 MDS_TESTS+=" mds_tell_help_command"
 
 MGR_TESTS+=" mgr_tell"
+MGR_TESTS+=" mgr_devices"
 
 TESTS+=$MON_TESTS
 TESTS+=$OSD_TESTS
diff --git a/src/mgr/ActivePyModules.cc b/src/mgr/ActivePyModules.cc
index 907bb0c81c93..444de30f3d8e 100644
--- a/src/mgr/ActivePyModules.cc
+++ b/src/mgr/ActivePyModules.cc
@@ -314,10 +314,15 @@ PyObject *ActivePyModules::get_python(const std::string &what)
   } else if (what.size() > 7 &&
 	     what.substr(0, 7) == "device ") {
     string devid = what.substr(7);
-    daemon_state.with_device(devid, [&f, &tstate] (const DeviceState& dev) {
-        PyEval_RestoreThread(tstate);
-	f.dump_object("device", dev);
-      });
+    if (!daemon_state.with_device(
+	  devid,
+	  [&f, &tstate] (const DeviceState& dev) {
+	    PyEval_RestoreThread(tstate);
+	    f.dump_object("device", dev);
+	  })) {
+      // device not found
+      PyEval_RestoreThread(tstate);
+    }
     return f.get();
   } else if (what == "io_rate") {
     cluster_state.with_pgmap(
-- 
2.47.3