gdb/systemd: enable minidebuginfo support conditionally

Enabling minidebuginfo is not useful if gdb and systemd-coredump
are unable to parse it.

In order to parse it, gdb needs xz support. Systemd needs coredump enabled, as
well as elfutil enabled as well (systemd-coredump loads libdw which is part of elfutils using dlopen).

(From OE-Core rev: 0d2df803bebfd7e832ab7da54c4dacaaeeb424a9)

Signed-off-by: Etienne Cordonnier <ecordonnier@snap.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/lib/oe/package.py

@@ -1239,7 +1239,7 @@ def process_split_and_strip_files(d):
         oe.utils.multiprocess_launch(oe.package.runstrip, sfiles, d)
 
     # Build "minidebuginfo" and reinject it back into the stripped binaries
-    if d.getVar('PACKAGE_MINIDEBUGINFO') == '1':
+    if bb.utils.contains('DISTRO_FEATURES', 'minidebuginfo', True, False, d):
         oe.utils.multiprocess_launch(inject_minidebuginfo, list(elffiles), d,
                                      extraargs=(dvar, dv, d))
 

meta/lib/oeqa/runtime/cases/systemd.py

@@ -5,6 +5,7 @@
 #
 
 import re
+import threading
 import time
 
 from oeqa.runtime.case import OERuntimeTestCase
@@ -136,6 +137,26 @@ class SystemdServiceTests(SystemdTest):
             status = self.target.run('mount -oro,remount /')[0]
             self.assertTrue(status == 0, msg='Remounting / as r/o failed')
 
+    @skipIfNotFeature('minidebuginfo', 'Test requires minidebuginfo to be in DISTRO_FEATURES')
+    @OEHasPackage(['busybox'])
+    def test_systemd_coredump_minidebuginfo(self):
+        """
+        Verify that call-stacks generated by systemd-coredump contain symbolicated call-stacks,
+        extracted from the minidebuginfo metadata (.gnu_debugdata elf section).
+        """
+        t_thread = threading.Thread(target=self.target.run, args=("ulimit -c unlimited && sleep 1000",))
+        t_thread.start()
+        time.sleep(1)
+
+        status, output = self.target.run('pidof sleep')
+        # cause segfault on purpose
+        self.target.run('kill -SEGV %s' % output)
+        self.assertEqual(status, 0, msg = 'Not able to find process that runs sleep, output : %s' % output)
+
+        (status, output) = self.target.run('coredumpctl info')
+        self.assertEqual(status, 0, msg='MiniDebugInfo Test failed: %s' % output)
+        self.assertEqual('sleep_for_duration (busybox.nosuid' in output, True, msg='Call stack is missing minidebuginfo symbols (functions shown as "n/a"): %s' % output)
+
 class SystemdJournalTests(SystemdTest):
 
     @OETestDepends(['systemd.SystemdBasicTests.test_systemd_basic'])

meta/lib/oeqa/selftest/cases/minidebuginfo.py

@@ -21,7 +21,7 @@ class Minidebuginfo(OESelftestTestCase):
         bb_vars = get_bb_vars(['DEPLOY_DIR_IMAGE', 'IMAGE_LINK_NAME', 'READELF'], image)
 
         self.write_config("""
-PACKAGE_MINIDEBUGINFO = "1"
+DISTRO_FEATURES:append = " minidebuginfo"
 IMAGE_FSTYPES = "tar.bz2"
 """)
         bitbake("{} {}:do_addto_recipe_sysroot".format(image, binutils))