[PATCH v9 00/16] qemu_iotests: improve debugging options

[PATCH v9 00/16] qemu_iotests: improve debugging options

[Emanuele Giuseppe Esposito]

This series adds the option to attach gdbserver and valgrind
to the QEMU binary running in qemu_iotests.
It also allows to redirect QEMU binaries output of the python tests
to the stdout, instead of a log file.

Patches 1-9 introduce the -gdb option to both python and bash tests, 
10-14 extend the already existing -valgrind flag to work also on 
python tests, and patch 15-16 introduces -p to enable logging to stdout.

In particular, patches 1,6,8,11 focus on extending the QMP socket timers
when using gdb/valgrind, otherwise the python tests will fail due to
delays in the QMP responses.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
---
v9:
* Replace `! -z` with `-n` in bash scripts (patch 8), and quote $GDB_OPTIONS in
  the same if condition [Max]
* Add r-b from Max to all patches except 8, remove r-b from Vladimir on patch 8

Emanuele Giuseppe Esposito (15):
  python: qemu: add timer parameter for qmp.accept socket
  python: qemu: pass the wrapper field from QEMUQtestmachine to
    QEMUMachine
  docs/devel/testing: add debug section to the QEMU iotests chapter
  qemu-iotests: add option to attach gdbserver
  qemu-iotests: delay QMP socket timers
  qemu_iotests: insert gdbserver command line as wrapper for qemu binary
  qemu-iotests: add gdbserver option to script tests too
  docs/devel/testing: add -gdb option to the debugging section of QEMU
    iotests
  qemu-iotests: extend the check script to prepare supporting valgrind
    for python tests
  qemu-iotests: extend QMP socket timeout when using valgrind
  qemu-iotests: allow valgrind to read/delete the generated log file
  qemu-iotests: insert valgrind command line as wrapper for qemu binary
  docs/devel/testing: add -valgrind option to the debug section of QEMU
    iotests
  qemu-iotests: add option to show qemu binary logs on stdout
  docs/devel/testing: add -p option to the debug section of QEMU iotests

John Snow (1):
  python: Reduce strictness of pylint's duplicate-code check

 docs/devel/testing.rst         | 29 ++++++++++++++++++++
 python/qemu/machine/machine.py | 16 +++++++----
 python/qemu/machine/qtest.py   |  9 ++++---
 python/setup.cfg               |  5 ++++
 tests/qemu-iotests/check       | 15 ++++++++---
 tests/qemu-iotests/common.qemu |  7 ++++-
 tests/qemu-iotests/common.rc   |  8 +++++-
 tests/qemu-iotests/iotests.py  | 49 ++++++++++++++++++++++++++++++++--
 tests/qemu-iotests/testenv.py  | 23 ++++++++++++++--
 9 files changed, 143 insertions(+), 18 deletions(-)

-- 
2.31.1

[PATCH v9 01/16] python: qemu: add timer parameter for qmp.accept socket

[Emanuele Giuseppe Esposito]

Also add a new _qmp_timer field to the QEMUMachine class.

Let's change the default socket timeout to None, so that if
a subclass needs to add a timer, it can be done by modifying
this private field.

At the same time, restore the timer to be 15 seconds in iotests.py, to
give an upper bound to the QMP monitor test command execution.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Acked-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
 python/qemu/machine/machine.py | 7 +++++--
 python/qemu/machine/qtest.py   | 5 +++--
 tests/qemu-iotests/iotests.py  | 3 ++-
 3 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/python/qemu/machine/machine.py b/python/qemu/machine/machine.py
index 971ed7e8c6..14c4d17eca 100644
--- a/python/qemu/machine/machine.py
+++ b/python/qemu/machine/machine.py
@@ -97,7 +97,8 @@ def __init__(self,
                  sock_dir: Optional[str] = None,
                  drain_console: bool = False,
                  console_log: Optional[str] = None,
-                 log_dir: Optional[str] = None):
+                 log_dir: Optional[str] = None,
+                 qmp_timer: Optional[float] = None):
         '''
         Initialize a QEMUMachine
 
@@ -112,6 +113,7 @@ def __init__(self,
         @param drain_console: (optional) True to drain console socket to buffer
         @param console_log: (optional) path to console log file
         @param log_dir: where to create and keep log files
+        @param qmp_timer: (optional) default QMP socket timeout
         @note: Qemu process is not started until launch() is used.
         '''
         # pylint: disable=too-many-arguments
@@ -121,6 +123,7 @@ def __init__(self,
         self._binary = binary
         self._args = list(args)
         self._wrapper = wrapper
+        self._qmp_timer = qmp_timer
 
         self._name = name or "qemu-%d" % os.getpid()
         self._base_temp_dir = base_temp_dir
@@ -343,7 +346,7 @@ def _pre_launch(self) -> None:
 
     def _post_launch(self) -> None:
         if self._qmp_connection:
-            self._qmp.accept()
+            self._qmp.accept(self._qmp_timer)
 
     def _post_shutdown(self) -> None:
         """
diff --git a/python/qemu/machine/qtest.py b/python/qemu/machine/qtest.py
index d6d9c6a34a..592be263e0 100644
--- a/python/qemu/machine/qtest.py
+++ b/python/qemu/machine/qtest.py
@@ -115,7 +115,8 @@ def __init__(self,
                  name: Optional[str] = None,
                  base_temp_dir: str = "/var/tmp",
                  socket_scm_helper: Optional[str] = None,
-                 sock_dir: Optional[str] = None):
+                 sock_dir: Optional[str] = None,
+                 qmp_timer: Optional[float] = None):
         # pylint: disable=too-many-arguments
 
         if name is None:
@@ -124,7 +125,7 @@ def __init__(self,
             sock_dir = base_temp_dir
         super().__init__(binary, args, name=name, base_temp_dir=base_temp_dir,
                          socket_scm_helper=socket_scm_helper,
-                         sock_dir=sock_dir)
+                         sock_dir=sock_dir, qmp_timer=qmp_timer)
         self._qtest: Optional[QEMUQtestProtocol] = None
         self._qtest_path = os.path.join(sock_dir, name + "-qtest.sock")
 
diff --git a/tests/qemu-iotests/iotests.py b/tests/qemu-iotests/iotests.py
index 89663dac06..6b0db4ce54 100644
--- a/tests/qemu-iotests/iotests.py
+++ b/tests/qemu-iotests/iotests.py
@@ -570,10 +570,11 @@ class VM(qtest.QEMUQtestMachine):
 
     def __init__(self, path_suffix=''):
         name = "qemu%s-%d" % (path_suffix, os.getpid())
+        timer = 15.0
         super().__init__(qemu_prog, qemu_opts, name=name,
                          base_temp_dir=test_dir,
                          socket_scm_helper=socket_scm_helper,
-                         sock_dir=sock_dir)
+                         sock_dir=sock_dir, qmp_timer=timer)
         self._num_drives = 0
 
     def add_object(self, opts):
-- 
2.31.1

[PATCH v9 02/16] python: Reduce strictness of pylint's duplicate-code check

[Emanuele Giuseppe Esposito]

From: John Snow <jsnow@redhat.com>

Pylint prior to 2.8.3 (We pin at >= 2.8.0) includes function and method
signatures as part of its duplicate checking algorithm. This check does
not listen to pragmas, so the only way to disable it is to turn it off
completely or increase the minimum duplicate lines so that it doesn't
trigger for functions with long, multi-line signatures.

When we decide to upgrade to pylint 2.8.3 or greater, we will be able to
use 'ignore-signatures = true' to the config instead.

I'd prefer not to keep us on the very bleeding edge of pylint if I can
help it -- 2.8.3 came out only three days ago at time of writing.

See: https://github.com/PyCQA/pylint/pull/4474
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Acked-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
 python/setup.cfg | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/python/setup.cfg b/python/setup.cfg
index 14bab90288..83909c1c97 100644
--- a/python/setup.cfg
+++ b/python/setup.cfg
@@ -105,6 +105,11 @@ good-names=i,
 # Ignore imports when computing similarities.
 ignore-imports=yes
 
+# Minimum lines number of a similarity.
+# TODO: Remove after we opt in to Pylint 2.8.3. See commit msg.
+min-similarity-lines=6
+
+
 [isort]
 force_grid_wrap=4
 force_sort_within_sections=True
-- 
2.31.1

[PATCH v9 03/16] python: qemu: pass the wrapper field from QEMUQtestmachine to QEMUMachine

[Emanuele Giuseppe Esposito]

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Acked-by: John Snow <jsnow@redhat.com>
---
 python/qemu/machine/qtest.py | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/python/qemu/machine/qtest.py b/python/qemu/machine/qtest.py
index 592be263e0..395cc8fbfe 100644
--- a/python/qemu/machine/qtest.py
+++ b/python/qemu/machine/qtest.py
@@ -112,6 +112,7 @@ class QEMUQtestMachine(QEMUMachine):
     def __init__(self,
                  binary: str,
                  args: Sequence[str] = (),
+                 wrapper: Sequence[str] = (),
                  name: Optional[str] = None,
                  base_temp_dir: str = "/var/tmp",
                  socket_scm_helper: Optional[str] = None,
@@ -123,7 +124,8 @@ def __init__(self,
             name = "qemu-%d" % os.getpid()
         if sock_dir is None:
             sock_dir = base_temp_dir
-        super().__init__(binary, args, name=name, base_temp_dir=base_temp_dir,
+        super().__init__(binary, args, wrapper=wrapper, name=name,
+                         base_temp_dir=base_temp_dir,
                          socket_scm_helper=socket_scm_helper,
                          sock_dir=sock_dir, qmp_timer=qmp_timer)
         self._qtest: Optional[QEMUQtestProtocol] = None
-- 
2.31.1

[PATCH v9 04/16] docs/devel/testing: add debug section to the QEMU iotests chapter

[Emanuele Giuseppe Esposito]

Introduce the "Debugging a test case" section, in preparation
to the additional flags that will be added in the next patches.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
 docs/devel/testing.rst | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/docs/devel/testing.rst b/docs/devel/testing.rst
index 8a9cda33a5..8359f2ae37 100644
--- a/docs/devel/testing.rst
+++ b/docs/devel/testing.rst
@@ -224,6 +224,14 @@ another application on the host may have locked the file, possibly leading to a
 test failure.  If using such devices are explicitly desired, consider adding
 ``locking=off`` option to disable image locking.
 
+Debugging a test case
+-----------------------
+The following options to the ``check`` script can be useful when debugging
+a failing test:
+
+* ``-d`` (debug) just increases the logging verbosity, showing
+  for example the QMP commands and answers.
+
 Test case groups
 ----------------
 
-- 
2.31.1

[PATCH v9 05/16] qemu-iotests: add option to attach gdbserver

[Emanuele Giuseppe Esposito]

Define -gdb flag and GDB_OPTIONS environment variable
to python tests to attach a gdbserver to each qemu instance.
This patch only adds and parses this flag, it does not yet add
the implementation for it.

if -gdb is not provided but $GDB_OPTIONS is set, ignore the
environment variable.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
 tests/qemu-iotests/check      |  6 +++++-
 tests/qemu-iotests/iotests.py |  5 +++++
 tests/qemu-iotests/testenv.py | 17 +++++++++++++++--
 3 files changed, 25 insertions(+), 3 deletions(-)

diff --git a/tests/qemu-iotests/check b/tests/qemu-iotests/check
index 2dd529eb75..4365bb8066 100755
--- a/tests/qemu-iotests/check
+++ b/tests/qemu-iotests/check
@@ -36,6 +36,9 @@ def make_argparser() -> argparse.ArgumentParser:
                    help='pretty print output for make check')
 
     p.add_argument('-d', dest='debug', action='store_true', help='debug')
+    p.add_argument('-gdb', action='store_true',
+                   help="start gdbserver with $GDB_OPTIONS options \
+                        ('localhost:12345' if $GDB_OPTIONS is empty)")
     p.add_argument('-misalign', action='store_true',
                    help='misalign memory allocations')
     p.add_argument('--color', choices=['on', 'off', 'auto'],
@@ -114,7 +117,8 @@ if __name__ == '__main__':
     env = TestEnv(imgfmt=args.imgfmt, imgproto=args.imgproto,
                   aiomode=args.aiomode, cachemode=args.cachemode,
                   imgopts=args.imgopts, misalign=args.misalign,
-                  debug=args.debug, valgrind=args.valgrind)
+                  debug=args.debug, valgrind=args.valgrind,
+                  gdb=args.gdb)
 
     if len(sys.argv) > 1 and sys.argv[-len(args.tests)-1] == '--':
         if not args.tests:
diff --git a/tests/qemu-iotests/iotests.py b/tests/qemu-iotests/iotests.py
index 6b0db4ce54..c86f239d81 100644
--- a/tests/qemu-iotests/iotests.py
+++ b/tests/qemu-iotests/iotests.py
@@ -74,6 +74,11 @@
 qemu_prog = os.environ.get('QEMU_PROG', 'qemu')
 qemu_opts = os.environ.get('QEMU_OPTIONS', '').strip().split(' ')
 
+gdb_qemu_env = os.environ.get('GDB_OPTIONS')
+qemu_gdb = []
+if gdb_qemu_env:
+    qemu_gdb = ['gdbserver'] + gdb_qemu_env.strip().split(' ')
+
 imgfmt = os.environ.get('IMGFMT', 'raw')
 imgproto = os.environ.get('IMGPROTO', 'file')
 output_dir = os.environ.get('OUTPUT_DIR', '.')
diff --git a/tests/qemu-iotests/testenv.py b/tests/qemu-iotests/testenv.py
index 0c3fe75636..8501c6caf5 100644
--- a/tests/qemu-iotests/testenv.py
+++ b/tests/qemu-iotests/testenv.py
@@ -27,6 +27,7 @@
 import glob
 from typing import List, Dict, Any, Optional, ContextManager
 
+DEF_GDB_OPTIONS = 'localhost:12345'
 
 def isxfile(path: str) -> bool:
     return os.path.isfile(path) and os.access(path, os.X_OK)
@@ -72,7 +73,8 @@ class TestEnv(ContextManager['TestEnv']):
                      'QEMU_NBD_OPTIONS', 'IMGOPTS', 'IMGFMT', 'IMGPROTO',
                      'AIOMODE', 'CACHEMODE', 'VALGRIND_QEMU',
                      'CACHEMODE_IS_DEFAULT', 'IMGFMT_GENERIC', 'IMGOPTSSYNTAX',
-                     'IMGKEYSECRET', 'QEMU_DEFAULT_MACHINE', 'MALLOC_PERTURB_']
+                     'IMGKEYSECRET', 'QEMU_DEFAULT_MACHINE', 'MALLOC_PERTURB_',
+                     'GDB_OPTIONS']
 
     def prepare_subprocess(self, args: List[str]) -> Dict[str, str]:
         if self.debug:
@@ -178,7 +180,8 @@ def __init__(self, imgfmt: str, imgproto: str, aiomode: str,
                  imgopts: Optional[str] = None,
                  misalign: bool = False,
                  debug: bool = False,
-                 valgrind: bool = False) -> None:
+                 valgrind: bool = False,
+                 gdb: bool = False) -> None:
         self.imgfmt = imgfmt
         self.imgproto = imgproto
         self.aiomode = aiomode
@@ -186,6 +189,15 @@ def __init__(self, imgfmt: str, imgproto: str, aiomode: str,
         self.misalign = misalign
         self.debug = debug
 
+        if gdb:
+            self.gdb_options = os.getenv('GDB_OPTIONS', DEF_GDB_OPTIONS)
+            if not self.gdb_options:
+                # cover the case 'export GDB_OPTIONS='
+                self.gdb_options = DEF_GDB_OPTIONS
+        elif 'GDB_OPTIONS' in os.environ:
+            # to not propagate it in prepare_subprocess()
+            del os.environ['GDB_OPTIONS']
+
         if valgrind:
             self.valgrind_qemu = 'y'
 
@@ -285,6 +297,7 @@ def print_env(self) -> None:
 TEST_DIR      -- {TEST_DIR}
 SOCK_DIR      -- {SOCK_DIR}
 SOCKET_SCM_HELPER -- {SOCKET_SCM_HELPER}
+GDB_OPTIONS   -- {GDB_OPTIONS}
 """
 
         args = collections.defaultdict(str, self.get_env())
-- 
2.31.1

[PATCH v9 06/16] qemu-iotests: delay QMP socket timers

[Emanuele Giuseppe Esposito]

Attaching gdbserver implies that the qmp socket
should wait indefinitely for an answer from QEMU.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
 tests/qemu-iotests/iotests.py | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/tests/qemu-iotests/iotests.py b/tests/qemu-iotests/iotests.py
index c86f239d81..e176a84620 100644
--- a/tests/qemu-iotests/iotests.py
+++ b/tests/qemu-iotests/iotests.py
@@ -477,10 +477,14 @@ def __init__(self, seconds, errmsg="Timeout"):
         self.seconds = seconds
         self.errmsg = errmsg
     def __enter__(self):
+        if qemu_gdb:
+            return self
         signal.signal(signal.SIGALRM, self.timeout)
         signal.setitimer(signal.ITIMER_REAL, self.seconds)
         return self
     def __exit__(self, exc_type, value, traceback):
+        if qemu_gdb:
+            return False
         signal.setitimer(signal.ITIMER_REAL, 0)
         return False
     def timeout(self, signum, frame):
@@ -575,7 +579,7 @@ class VM(qtest.QEMUQtestMachine):
 
     def __init__(self, path_suffix=''):
         name = "qemu%s-%d" % (path_suffix, os.getpid())
-        timer = 15.0
+        timer = 15.0 if not qemu_gdb else None
         super().__init__(qemu_prog, qemu_opts, name=name,
                          base_temp_dir=test_dir,
                          socket_scm_helper=socket_scm_helper,
-- 
2.31.1

[PATCH v9 07/16] qemu_iotests: insert gdbserver command line as wrapper for qemu binary

[Emanuele Giuseppe Esposito]

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
 tests/qemu-iotests/iotests.py | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/tests/qemu-iotests/iotests.py b/tests/qemu-iotests/iotests.py
index e176a84620..e7e3d92d3e 100644
--- a/tests/qemu-iotests/iotests.py
+++ b/tests/qemu-iotests/iotests.py
@@ -580,7 +580,8 @@ class VM(qtest.QEMUQtestMachine):
     def __init__(self, path_suffix=''):
         name = "qemu%s-%d" % (path_suffix, os.getpid())
         timer = 15.0 if not qemu_gdb else None
-        super().__init__(qemu_prog, qemu_opts, name=name,
+        super().__init__(qemu_prog, qemu_opts, wrapper=qemu_gdb,
+                         name=name,
                          base_temp_dir=test_dir,
                          socket_scm_helper=socket_scm_helper,
                          sock_dir=sock_dir, qmp_timer=timer)
-- 
2.31.1

[PATCH v9 08/16] qemu-iotests: add gdbserver option to script tests too

[Emanuele Giuseppe Esposito]

Remove read timer in test script when GDB_OPTIONS are set,
so that the bash tests won't timeout while running gdb.

The only limitation here is that running a script with gdbserver
will make the test output mismatch with the expected
results, making the test fail.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
---
 tests/qemu-iotests/common.qemu | 7 ++++++-
 tests/qemu-iotests/common.rc   | 8 +++++++-
 2 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/tests/qemu-iotests/common.qemu b/tests/qemu-iotests/common.qemu
index 0fc52d20d7..0f1fecc68e 100644
--- a/tests/qemu-iotests/common.qemu
+++ b/tests/qemu-iotests/common.qemu
@@ -85,7 +85,12 @@ _timed_wait_for()
     timeout=yes
 
     QEMU_STATUS[$h]=0
-    while IFS= read -t ${QEMU_COMM_TIMEOUT} resp <&${QEMU_OUT[$h]}
+    read_timeout="-t ${QEMU_COMM_TIMEOUT}"
+    if [ -n "${GDB_OPTIONS}" ]; then
+        read_timeout=
+    fi
+
+    while IFS= read ${read_timeout} resp <&${QEMU_OUT[$h]}
     do
         if [ -n "$capture_events" ]; then
             capture=0
diff --git a/tests/qemu-iotests/common.rc b/tests/qemu-iotests/common.rc
index 609d82de89..d8582454de 100644
--- a/tests/qemu-iotests/common.rc
+++ b/tests/qemu-iotests/common.rc
@@ -166,8 +166,14 @@ _qemu_wrapper()
         if [ -n "${QEMU_NEED_PID}" ]; then
             echo $BASHPID > "${QEMU_TEST_DIR}/qemu-${_QEMU_HANDLE}.pid"
         fi
+
+        GDB=""
+        if [ -n "${GDB_OPTIONS}" ]; then
+            GDB="gdbserver ${GDB_OPTIONS}"
+        fi
+
         VALGRIND_QEMU="${VALGRIND_QEMU_VM}" _qemu_proc_exec "${VALGRIND_LOGFILE}" \
-            "$QEMU_PROG" $QEMU_OPTIONS "$@"
+            $GDB "$QEMU_PROG" $QEMU_OPTIONS "$@"
     )
     RETVAL=$?
     _qemu_proc_valgrind_log "${VALGRIND_LOGFILE}" $RETVAL
-- 
2.31.1

[PATCH v9 09/16] docs/devel/testing: add -gdb option to the debugging section of QEMU iotests

[Emanuele Giuseppe Esposito]

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
 docs/devel/testing.rst | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/docs/devel/testing.rst b/docs/devel/testing.rst
index 8359f2ae37..01e1919873 100644
--- a/docs/devel/testing.rst
+++ b/docs/devel/testing.rst
@@ -229,6 +229,17 @@ Debugging a test case
 The following options to the ``check`` script can be useful when debugging
 a failing test:
 
+* ``-gdb`` wraps every QEMU invocation in a ``gdbserver``, which waits for a
+  connection from a gdb client.  The options given to ``gdbserver`` (e.g. the
+  address on which to listen for connections) are taken from the ``$GDB_OPTIONS``
+  environment variable.  By default (if ``$GDB_OPTIONS`` is empty), it listens on
+  ``localhost:12345``.
+  It is possible to connect to it for example with
+  ``gdb -iex "target remote $addr"``, where ``$addr`` is the address
+  ``gdbserver`` listens on.
+  If the ``-gdb`` option is not used, ``$GDB_OPTIONS`` is ignored,
+  regardless of whether it is set or not.
+
 * ``-d`` (debug) just increases the logging verbosity, showing
   for example the QMP commands and answers.
 
-- 
2.31.1

[PATCH v9 10/16] qemu-iotests: extend the check script to prepare supporting valgrind for python tests

[Emanuele Giuseppe Esposito]

Currently, the check script only parses the option and sets the
VALGRIND_QEMU environmental variable to "y".
Add another local python variable that prepares the command line,
identical to the one provided in the test scripts.

Because the python script does not know in advance the valgrind
PID to assign to the log file name, use the "%p" flag in valgrind
log file name that automatically puts the process PID at runtime.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
---
 tests/qemu-iotests/check      |  7 ++++---
 tests/qemu-iotests/iotests.py | 11 +++++++++++
 tests/qemu-iotests/testenv.py |  1 +
 3 files changed, 16 insertions(+), 3 deletions(-)

diff --git a/tests/qemu-iotests/check b/tests/qemu-iotests/check
index 4365bb8066..ebd27946db 100755
--- a/tests/qemu-iotests/check
+++ b/tests/qemu-iotests/check
@@ -39,6 +39,10 @@ def make_argparser() -> argparse.ArgumentParser:
     p.add_argument('-gdb', action='store_true',
                    help="start gdbserver with $GDB_OPTIONS options \
                         ('localhost:12345' if $GDB_OPTIONS is empty)")
+    p.add_argument('-valgrind', action='store_true',
+                    help='use valgrind, sets VALGRIND_QEMU environment '
+                    'variable')
+
     p.add_argument('-misalign', action='store_true',
                    help='misalign memory allocations')
     p.add_argument('--color', choices=['on', 'off', 'auto'],
@@ -88,9 +92,6 @@ def make_argparser() -> argparse.ArgumentParser:
     g_bash.add_argument('-o', dest='imgopts',
                         help='options to pass to qemu-img create/convert, '
                         'sets IMGOPTS environment variable')
-    g_bash.add_argument('-valgrind', action='store_true',
-                        help='use valgrind, sets VALGRIND_QEMU environment '
-                        'variable')
 
     g_sel = p.add_argument_group('test selecting options',
                                  'The following options specify test set '
diff --git a/tests/qemu-iotests/iotests.py b/tests/qemu-iotests/iotests.py
index e7e3d92d3e..6aa1dc48ba 100644
--- a/tests/qemu-iotests/iotests.py
+++ b/tests/qemu-iotests/iotests.py
@@ -96,6 +96,17 @@
     sys.stderr.write('Please run this test via the "check" script\n')
     sys.exit(os.EX_USAGE)
 
+qemu_valgrind = []
+if os.environ.get('VALGRIND_QEMU') == "y" and \
+    os.environ.get('NO_VALGRIND') != "y":
+    valgrind_logfile = "--log-file=" + test_dir
+    # %p allows to put the valgrind process PID, since
+    # we don't know it a priori (subprocess.Popen is
+    # not yet invoked)
+    valgrind_logfile += "/%p.valgrind"
+
+    qemu_valgrind = ['valgrind', valgrind_logfile, '--error-exitcode=99']
+
 socket_scm_helper = os.environ.get('SOCKET_SCM_HELPER', 'socket_scm_helper')
 
 luks_default_secret_object = 'secret,id=keysec0,data=' + \
diff --git a/tests/qemu-iotests/testenv.py b/tests/qemu-iotests/testenv.py
index 8501c6caf5..8bf154376f 100644
--- a/tests/qemu-iotests/testenv.py
+++ b/tests/qemu-iotests/testenv.py
@@ -298,6 +298,7 @@ def print_env(self) -> None:
 SOCK_DIR      -- {SOCK_DIR}
 SOCKET_SCM_HELPER -- {SOCKET_SCM_HELPER}
 GDB_OPTIONS   -- {GDB_OPTIONS}
+VALGRIND_QEMU -- {VALGRIND_QEMU}
 """
 
         args = collections.defaultdict(str, self.get_env())
-- 
2.31.1

[PATCH v9 11/16] qemu-iotests: extend QMP socket timeout when using valgrind

[Emanuele Giuseppe Esposito]

As with gdbserver, valgrind delays the test execution, so
the default QMP socket timeout and the generic class
Timeout in iotests.py timeouts too soon.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
 tests/qemu-iotests/iotests.py | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/tests/qemu-iotests/iotests.py b/tests/qemu-iotests/iotests.py
index 6aa1dc48ba..26c580f9e7 100644
--- a/tests/qemu-iotests/iotests.py
+++ b/tests/qemu-iotests/iotests.py
@@ -488,13 +488,13 @@ def __init__(self, seconds, errmsg="Timeout"):
         self.seconds = seconds
         self.errmsg = errmsg
     def __enter__(self):
-        if qemu_gdb:
+        if qemu_gdb or qemu_valgrind:
             return self
         signal.signal(signal.SIGALRM, self.timeout)
         signal.setitimer(signal.ITIMER_REAL, self.seconds)
         return self
     def __exit__(self, exc_type, value, traceback):
-        if qemu_gdb:
+        if qemu_gdb or qemu_valgrind:
             return False
         signal.setitimer(signal.ITIMER_REAL, 0)
         return False
@@ -590,7 +590,7 @@ class VM(qtest.QEMUQtestMachine):
 
     def __init__(self, path_suffix=''):
         name = "qemu%s-%d" % (path_suffix, os.getpid())
-        timer = 15.0 if not qemu_gdb else None
+        timer = 15.0 if not (qemu_gdb or qemu_valgrind) else None
         super().__init__(qemu_prog, qemu_opts, wrapper=qemu_gdb,
                          name=name,
                          base_temp_dir=test_dir,
-- 
2.31.1

[PATCH v9 12/16] qemu-iotests: allow valgrind to read/delete the generated log file

[Emanuele Giuseppe Esposito]

When using -valgrind on the script tests, it generates a log file
in $TEST_DIR that is either read (if valgrind finds problems) or
otherwise deleted. Provide the same exact behavior when using
-valgrind on the python tests.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
 tests/qemu-iotests/iotests.py | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/tests/qemu-iotests/iotests.py b/tests/qemu-iotests/iotests.py
index 26c580f9e7..85d8c0abbb 100644
--- a/tests/qemu-iotests/iotests.py
+++ b/tests/qemu-iotests/iotests.py
@@ -598,6 +598,17 @@ def __init__(self, path_suffix=''):
                          sock_dir=sock_dir, qmp_timer=timer)
         self._num_drives = 0
 
+    def _post_shutdown(self) -> None:
+        super()._post_shutdown()
+        if not qemu_valgrind or not self._popen:
+            return
+        valgrind_filename =  f"{test_dir}/{self._popen.pid}.valgrind"
+        if self.exitcode() == 99:
+            with open(valgrind_filename) as f:
+                print(f.read())
+        else:
+            os.remove(valgrind_filename)
+
     def add_object(self, opts):
         self._args.append('-object')
         self._args.append(opts)
-- 
2.31.1

[PATCH v9 13/16] qemu-iotests: insert valgrind command line as wrapper for qemu binary

[Emanuele Giuseppe Esposito]

If -gdb and -valgrind are both defined, return an error.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
 tests/qemu-iotests/iotests.py | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/tests/qemu-iotests/iotests.py b/tests/qemu-iotests/iotests.py
index 85d8c0abbb..74fa56840d 100644
--- a/tests/qemu-iotests/iotests.py
+++ b/tests/qemu-iotests/iotests.py
@@ -591,7 +591,11 @@ class VM(qtest.QEMUQtestMachine):
     def __init__(self, path_suffix=''):
         name = "qemu%s-%d" % (path_suffix, os.getpid())
         timer = 15.0 if not (qemu_gdb or qemu_valgrind) else None
-        super().__init__(qemu_prog, qemu_opts, wrapper=qemu_gdb,
+        if qemu_gdb and qemu_valgrind:
+            sys.stderr.write('gdb and valgrind are mutually exclusive\n')
+            sys.exit(1)
+        wrapper = qemu_gdb if qemu_gdb else qemu_valgrind
+        super().__init__(qemu_prog, qemu_opts, wrapper=wrapper,
                          name=name,
                          base_temp_dir=test_dir,
                          socket_scm_helper=socket_scm_helper,
-- 
2.31.1

[PATCH v9 14/16] docs/devel/testing: add -valgrind option to the debug section of QEMU iotests

[Emanuele Giuseppe Esposito]

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
---
 docs/devel/testing.rst | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/docs/devel/testing.rst b/docs/devel/testing.rst
index 01e1919873..8ebcf85a31 100644
--- a/docs/devel/testing.rst
+++ b/docs/devel/testing.rst
@@ -240,6 +240,12 @@ a failing test:
   If the ``-gdb`` option is not used, ``$GDB_OPTIONS`` is ignored,
   regardless of whether it is set or not.
 
+* ``-valgrind`` attaches a valgrind instance to QEMU. If it detects
+  warnings, it will print and save the log in
+  ``$TEST_DIR/<valgrind_pid>.valgrind``.
+  The final command line will be ``valgrind --log-file=$TEST_DIR/
+  <valgrind_pid>.valgrind --error-exitcode=99 $QEMU ...``
+
 * ``-d`` (debug) just increases the logging verbosity, showing
   for example the QMP commands and answers.
 
-- 
2.31.1

[PATCH v9 15/16] qemu-iotests: add option to show qemu binary logs on stdout

[Emanuele Giuseppe Esposito]

Using the flag -p, allow the qemu binary to print to stdout.

Also create the common function _close_qemu_log_file() to
avoid accessing machine.py private fields directly and have
duplicate code.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
 python/qemu/machine/machine.py | 9 ++++++---
 tests/qemu-iotests/check       | 4 +++-
 tests/qemu-iotests/iotests.py  | 8 ++++++++
 tests/qemu-iotests/testenv.py  | 9 +++++++--
 4 files changed, 24 insertions(+), 6 deletions(-)

diff --git a/python/qemu/machine/machine.py b/python/qemu/machine/machine.py
index 14c4d17eca..8b935813e9 100644
--- a/python/qemu/machine/machine.py
+++ b/python/qemu/machine/machine.py
@@ -348,6 +348,11 @@ def _post_launch(self) -> None:
         if self._qmp_connection:
             self._qmp.accept(self._qmp_timer)
 
+    def _close_qemu_log_file(self) -> None:
+        if self._qemu_log_file is not None:
+            self._qemu_log_file.close()
+            self._qemu_log_file = None
+
     def _post_shutdown(self) -> None:
         """
         Called to cleanup the VM instance after the process has exited.
@@ -360,9 +365,7 @@ def _post_shutdown(self) -> None:
             self._qmp.close()
             self._qmp_connection = None
 
-        if self._qemu_log_file is not None:
-            self._qemu_log_file.close()
-            self._qemu_log_file = None
+        self._close_qemu_log_file()
 
         self._load_io_log()
 
diff --git a/tests/qemu-iotests/check b/tests/qemu-iotests/check
index ebd27946db..da1bfb839e 100755
--- a/tests/qemu-iotests/check
+++ b/tests/qemu-iotests/check
@@ -36,6 +36,8 @@ def make_argparser() -> argparse.ArgumentParser:
                    help='pretty print output for make check')
 
     p.add_argument('-d', dest='debug', action='store_true', help='debug')
+    p.add_argument('-p', dest='print', action='store_true',
+                help='redirects qemu\'s stdout and stderr to the test output')
     p.add_argument('-gdb', action='store_true',
                    help="start gdbserver with $GDB_OPTIONS options \
                         ('localhost:12345' if $GDB_OPTIONS is empty)")
@@ -119,7 +121,7 @@ if __name__ == '__main__':
                   aiomode=args.aiomode, cachemode=args.cachemode,
                   imgopts=args.imgopts, misalign=args.misalign,
                   debug=args.debug, valgrind=args.valgrind,
-                  gdb=args.gdb)
+                  gdb=args.gdb, qprint=args.print)
 
     if len(sys.argv) > 1 and sys.argv[-len(args.tests)-1] == '--':
         if not args.tests:
diff --git a/tests/qemu-iotests/iotests.py b/tests/qemu-iotests/iotests.py
index 74fa56840d..2cf5ff965b 100644
--- a/tests/qemu-iotests/iotests.py
+++ b/tests/qemu-iotests/iotests.py
@@ -79,6 +79,8 @@
 if gdb_qemu_env:
     qemu_gdb = ['gdbserver'] + gdb_qemu_env.strip().split(' ')
 
+qemu_print = os.environ.get('PRINT_QEMU', False)
+
 imgfmt = os.environ.get('IMGFMT', 'raw')
 imgproto = os.environ.get('IMGPROTO', 'file')
 output_dir = os.environ.get('OUTPUT_DIR', '.')
@@ -613,6 +615,12 @@ def _post_shutdown(self) -> None:
         else:
             os.remove(valgrind_filename)
 
+    def _pre_launch(self) -> None:
+        super()._pre_launch()
+        if qemu_print:
+            # set QEMU binary output to stdout
+            self._close_qemu_log_file()
+
     def add_object(self, opts):
         self._args.append('-object')
         self._args.append(opts)
diff --git a/tests/qemu-iotests/testenv.py b/tests/qemu-iotests/testenv.py
index 8bf154376f..70da0d60c8 100644
--- a/tests/qemu-iotests/testenv.py
+++ b/tests/qemu-iotests/testenv.py
@@ -74,7 +74,7 @@ class TestEnv(ContextManager['TestEnv']):
                      'AIOMODE', 'CACHEMODE', 'VALGRIND_QEMU',
                      'CACHEMODE_IS_DEFAULT', 'IMGFMT_GENERIC', 'IMGOPTSSYNTAX',
                      'IMGKEYSECRET', 'QEMU_DEFAULT_MACHINE', 'MALLOC_PERTURB_',
-                     'GDB_OPTIONS']
+                     'GDB_OPTIONS', 'PRINT_QEMU']
 
     def prepare_subprocess(self, args: List[str]) -> Dict[str, str]:
         if self.debug:
@@ -181,7 +181,8 @@ def __init__(self, imgfmt: str, imgproto: str, aiomode: str,
                  misalign: bool = False,
                  debug: bool = False,
                  valgrind: bool = False,
-                 gdb: bool = False) -> None:
+                 gdb: bool = False,
+                 qprint: bool = False) -> None:
         self.imgfmt = imgfmt
         self.imgproto = imgproto
         self.aiomode = aiomode
@@ -189,6 +190,9 @@ def __init__(self, imgfmt: str, imgproto: str, aiomode: str,
         self.misalign = misalign
         self.debug = debug
 
+        if qprint:
+            self.print_qemu = 'y'
+
         if gdb:
             self.gdb_options = os.getenv('GDB_OPTIONS', DEF_GDB_OPTIONS)
             if not self.gdb_options:
@@ -299,6 +303,7 @@ def print_env(self) -> None:
 SOCKET_SCM_HELPER -- {SOCKET_SCM_HELPER}
 GDB_OPTIONS   -- {GDB_OPTIONS}
 VALGRIND_QEMU -- {VALGRIND_QEMU}
+PRINT_QEMU_OUTPUT -- {PRINT_QEMU}
 """
 
         args = collections.defaultdict(str, self.get_env())
-- 
2.31.1

[PATCH v9 16/16] docs/devel/testing: add -p option to the debug section of QEMU iotests

[Emanuele Giuseppe Esposito]

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
 docs/devel/testing.rst | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/docs/devel/testing.rst b/docs/devel/testing.rst
index 8ebcf85a31..4a0abbf23d 100644
--- a/docs/devel/testing.rst
+++ b/docs/devel/testing.rst
@@ -249,6 +249,10 @@ a failing test:
 * ``-d`` (debug) just increases the logging verbosity, showing
   for example the QMP commands and answers.
 
+* ``-p`` (print) redirects QEMU’s stdout and stderr to the test output,
+  instead of saving it into a log file in
+  ``$TEST_DIR/qemu-machine-<random_string>``.
+
 Test case groups
 ----------------
 
-- 
2.31.1

Re: [PATCH v9 00/16] qemu_iotests: improve debugging options

[Hanna Reitz]

On 09.08.21 11:00, Emanuele Giuseppe Esposito wrote:
> This series adds the option to attach gdbserver and valgrind
> to the QEMU binary running in qemu_iotests.
> It also allows to redirect QEMU binaries output of the python tests
> to the stdout, instead of a log file.
>
> Patches 1-9 introduce the -gdb option to both python and bash tests,
> 10-14 extend the already existing -valgrind flag to work also on
> python tests, and patch 15-16 introduces -p to enable logging to stdout.
>
> In particular, patches 1,6,8,11 focus on extending the QMP socket timers
> when using gdb/valgrind, otherwise the python tests will fail due to
> delays in the QMP responses.
>
> Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
> ---
> v9:
> * Replace `! -z` with `-n` in bash scripts (patch 8), and quote $GDB_OPTIONS in
>    the same if condition [Max]
> * Add r-b from Max to all patches except 8, remove r-b from Vladimir on patch 8

Thanks!  Applied to my block-next branch for 6.2:

https://github.com/XanClic/qemu/commits/block-next

(Usually, I’d take test patches to the block branch regardless of where 
we are in the freeze, but with this quite long series I feel better 
putting it into block-next.)

Hanna