qemu-devel.nongnu.org archive mirror
 help / color / mirror / Atom feed
* [PATCH v2 0/5] yank: Add chardev tests and fixes
@ 2021-03-22 15:40 Lukas Straub
  2021-03-22 15:41 ` [PATCH v2 1/5] tests: Use the normal yank code instead of stubs in relevant tests Lukas Straub
                   ` (4 more replies)
  0 siblings, 5 replies; 6+ messages in thread
From: Lukas Straub @ 2021-03-22 15:40 UTC (permalink / raw)
  To: qemu-devel
  Cc: Laurent Vivier, Marc-Andre Lureau, Thomas Huth, Li Zhang, Paolo Bonzini

[-- Attachment #1: Type: text/plain, Size: 1365 bytes --]

Hello Everyone,
These patches increase test coverage for yank, add tests and fix bugs and
crashes in yank in combination with chardev-change.

Regards,
Lukas Straub

Changes:
-v2:
 -test: add license
 -test: factorize testcases to a single function
 -test: test chardev_change with initialization of new chardev failing
 -fix chardev_change with initialization of new chardev failing
 -add reviewed-by and tested-by tags

Based-on: <20210316135907.3646901-1-armbru@redhat.com>
([PATCH] yank: Avoid linking into executables that don't want it)

Alternative based on:
https://github.com/Lukey3332/qemu.git yank_next

Lukas Straub (5):
  tests: Use the normal yank code instead of stubs in relevant tests
  tests: Add tests for yank with the chardev-change case
  chardev/char.c: Move object_property_try_add_child out of chardev_new
  chardev/char.c: Always pass id to chardev_new
  chardev: Fix yank with the chardev-change case

 MAINTAINERS             |   1 +
 chardev/char-socket.c   |  20 +++-
 chardev/char.c          |  77 ++++++++++-----
 include/chardev/char.h  |   3 +
 tests/qtest/meson.build |   6 +-
 tests/unit/meson.build  |   5 +-
 tests/unit/test-yank.c  | 201 ++++++++++++++++++++++++++++++++++++++++
 7 files changed, 280 insertions(+), 33 deletions(-)
 create mode 100644 tests/unit/test-yank.c

--
2.30.2

[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 833 bytes --]

^ permalink raw reply	[flat|nested] 6+ messages in thread

* [PATCH v2 1/5] tests: Use the normal yank code instead of stubs in relevant tests
  2021-03-22 15:40 [PATCH v2 0/5] yank: Add chardev tests and fixes Lukas Straub
@ 2021-03-22 15:41 ` Lukas Straub
  2021-03-22 15:41 ` [PATCH v2 2/5] tests: Add tests for yank with the chardev-change case Lukas Straub
                   ` (3 subsequent siblings)
  4 siblings, 0 replies; 6+ messages in thread
From: Lukas Straub @ 2021-03-22 15:41 UTC (permalink / raw)
  To: qemu-devel
  Cc: Laurent Vivier, Marc-Andre Lureau, Thomas Huth, Li Zhang, Paolo Bonzini

[-- Attachment #1: Type: text/plain, Size: 2462 bytes --]

Use the normal yank code instead of stubs in relevant tests to
increase coverage and to ensure that registering and unregistering
of yank instances and functions is done correctly.

Signed-off-by: Lukas Straub <lukasstraub2@web.de>
---
 tests/qtest/meson.build | 6 +++---
 tests/unit/meson.build  | 4 ++--
 2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/tests/qtest/meson.build b/tests/qtest/meson.build
index 66ee9fbf45..40e1f495f7 100644
--- a/tests/qtest/meson.build
+++ b/tests/qtest/meson.build
@@ -234,9 +234,9 @@ tpmemu_files = ['tpm-emu.c', 'tpm-util.c', 'tpm-tests.c']
 qtests = {
   'bios-tables-test': [io, 'boot-sector.c', 'acpi-utils.c', 'tpm-emu.c'],
   'cdrom-test': files('boot-sector.c'),
-  'dbus-vmstate-test': files('migration-helpers.c') + dbus_vmstate1,
+  'dbus-vmstate-test': ['migration-helpers.c', dbus_vmstate1, '../../monitor/yank.c'],
   'ivshmem-test': [rt, '../../contrib/ivshmem-server/ivshmem-server.c'],
-  'migration-test': files('migration-helpers.c'),
+  'migration-test': ['migration-helpers.c', io, '../../monitor/yank.c'],
   'pxe-test': files('boot-sector.c'),
   'qos-test': [chardev, io, qos_test_ss.apply(config_host, strict: false).sources()],
   'tpm-crb-swtpm-test': [io, tpmemu_files],
@@ -266,7 +266,7 @@ foreach dir : target_dirs
   endif
   qtest_env.set('G_TEST_DBUS_DAEMON', meson.source_root() / 'tests/dbus-vmstate-daemon.sh')
   qtest_env.set('QTEST_QEMU_BINARY', './qemu-system-' + target_base)
-
+
   foreach test : target_qtests
     # Executables are shared across targets, declare them only the first time we
     # encounter them
diff --git a/tests/unit/meson.build b/tests/unit/meson.build
index 4bfe4627ba..8ccf60af66 100644
--- a/tests/unit/meson.build
+++ b/tests/unit/meson.build
@@ -123,7 +123,7 @@ if have_system
     'test-util-sockets': ['socket-helpers.c'],
     'test-base64': [],
     'test-bufferiszero': [],
-    'test-vmstate': [migration, io]
+    'test-vmstate': [migration, io, '../../monitor/yank.c']
   }
   if 'CONFIG_INOTIFY1' in config_host
     tests += {'test-util-filemonitor': []}
@@ -135,7 +135,7 @@ if have_system
   if 'CONFIG_TSAN' not in config_host
     if 'CONFIG_POSIX' in config_host
         tests += {
-          'test-char': ['socket-helpers.c', qom, io, chardev]
+          'test-char': ['socket-helpers.c', qom, io, chardev, '../../monitor/yank.c']
         }
     endif

--
2.30.2


[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 833 bytes --]

^ permalink raw reply related	[flat|nested] 6+ messages in thread

* [PATCH v2 2/5] tests: Add tests for yank with the chardev-change case
  2021-03-22 15:40 [PATCH v2 0/5] yank: Add chardev tests and fixes Lukas Straub
  2021-03-22 15:41 ` [PATCH v2 1/5] tests: Use the normal yank code instead of stubs in relevant tests Lukas Straub
@ 2021-03-22 15:41 ` Lukas Straub
  2021-03-22 15:41 ` [PATCH v2 3/5] chardev/char.c: Move object_property_try_add_child out of chardev_new Lukas Straub
                   ` (2 subsequent siblings)
  4 siblings, 0 replies; 6+ messages in thread
From: Lukas Straub @ 2021-03-22 15:41 UTC (permalink / raw)
  To: qemu-devel
  Cc: Laurent Vivier, Marc-Andre Lureau, Thomas Huth, Li Zhang, Paolo Bonzini

[-- Attachment #1: Type: text/plain, Size: 8142 bytes --]

Add tests for yank with the chardev-change case.

Signed-off-by: Lukas Straub <lukasstraub2@web.de>
---
 MAINTAINERS            |   1 +
 tests/unit/meson.build |   3 +-
 tests/unit/test-yank.c | 201 +++++++++++++++++++++++++++++++++++++++++
 3 files changed, 204 insertions(+), 1 deletion(-)
 create mode 100644 tests/unit/test-yank.c

diff --git a/MAINTAINERS b/MAINTAINERS
index aa024eed17..a8a7f0d1c2 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -2817,6 +2817,7 @@ F: monitor/yank.c
 F: stubs/yank.c
 F: include/qemu/yank.h
 F: qapi/yank.json
+F: tests/unit/test-yank.c

 COLO Framework
 M: zhanghailiang <zhang.zhanghailiang@huawei.com>
diff --git a/tests/unit/meson.build b/tests/unit/meson.build
index 8ccf60af66..38e5dba920 100644
--- a/tests/unit/meson.build
+++ b/tests/unit/meson.build
@@ -123,7 +123,8 @@ if have_system
     'test-util-sockets': ['socket-helpers.c'],
     'test-base64': [],
     'test-bufferiszero': [],
-    'test-vmstate': [migration, io, '../../monitor/yank.c']
+    'test-vmstate': [migration, io, '../../monitor/yank.c'],
+    'test-yank': ['socket-helpers.c', qom, io, chardev, '../../monitor/yank.c']
   }
   if 'CONFIG_INOTIFY1' in config_host
     tests += {'test-util-filemonitor': []}
diff --git a/tests/unit/test-yank.c b/tests/unit/test-yank.c
new file mode 100644
index 0000000000..5cb94c2fe4
--- /dev/null
+++ b/tests/unit/test-yank.c
@@ -0,0 +1,201 @@
+/*
+ * Tests for QEMU yank feature
+ *
+ * Copyright (c) Lukas Straub <lukasstraub2@web.de>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#include "qemu/osdep.h"
+#include <glib/gstdio.h>
+
+#include "qemu/config-file.h"
+#include "qemu/module.h"
+#include "qemu/option.h"
+#include "chardev/char-fe.h"
+#include "sysemu/sysemu.h"
+#include "qapi/error.h"
+#include "qapi/qapi-commands-char.h"
+#include "qapi/qapi-types-char.h"
+#include "qapi/qapi-commands-yank.h"
+#include "qapi/qapi-types-yank.h"
+#include "io/channel-socket.h"
+#include "socket-helpers.h"
+
+typedef struct {
+    SocketAddress *addr;
+    bool old_yank;
+    bool new_yank;
+    bool fail;
+} CharChangeTestConfig;
+
+static int chardev_change(void *opaque)
+{
+    return 0;
+}
+
+static bool is_yank_instance_registered(void)
+{
+    YankInstanceList *list;
+    bool ret;
+
+    list = qmp_query_yank(&error_abort);
+
+    ret = !!list;
+
+    qapi_free_YankInstanceList(list);
+
+    return ret;
+}
+
+static void char_change_test(gconstpointer opaque)
+{
+    CharChangeTestConfig *conf = (gpointer) opaque;
+    SocketAddress *addr;
+    Chardev *chr;
+    CharBackend be;
+    ChardevReturn *ret;
+    QIOChannelSocket *ioc;
+
+    /*
+     * Setup a listener socket and determine its address
+     * so we know the TCP port for the client later
+     */
+    ioc = qio_channel_socket_new();
+    g_assert_nonnull(ioc);
+    qio_channel_socket_listen_sync(ioc, conf->addr, 1, &error_abort);
+    addr = qio_channel_socket_get_local_address(ioc, &error_abort);
+    g_assert_nonnull(addr);
+
+    ChardevBackend backend[2] = {
+        /* doesn't support yank */
+        { .type = CHARDEV_BACKEND_KIND_NULL },
+        /* supports yank */
+        {
+            .type = CHARDEV_BACKEND_KIND_SOCKET,
+            .u.socket.data = &(ChardevSocket) {
+                .addr = &(SocketAddressLegacy) {
+                    .type = SOCKET_ADDRESS_LEGACY_KIND_INET,
+                    .u.inet.data = &addr->u.inet
+                },
+                .has_server = true,
+                .server = false
+            }
+        } };
+
+    ChardevBackend fail_backend[2] = {
+        /* doesn't support yank */
+        {
+            .type = CHARDEV_BACKEND_KIND_UDP,
+            .u.udp.data = &(ChardevUdp) {
+                .remote = &(SocketAddressLegacy) {
+                    .type = SOCKET_ADDRESS_LEGACY_KIND_UNIX,
+                    .u.q_unix.data = &(UnixSocketAddress) {
+                        .path = (char *)""
+                    }
+                }
+            }
+        },
+        /* supports yank */
+        {
+            .type = CHARDEV_BACKEND_KIND_SOCKET,
+            .u.socket.data = &(ChardevSocket) {
+                .addr = &(SocketAddressLegacy) {
+                    .type = SOCKET_ADDRESS_LEGACY_KIND_INET,
+                    .u.inet.data = &(InetSocketAddress) {
+                        .host = (char *)"127.0.0.1",
+                        .port = (char *)"0"
+                    }
+                },
+                .has_server = true,
+                .server = false
+            }
+        } };
+
+    g_assert(!is_yank_instance_registered());
+
+    ret = qmp_chardev_add("chardev", &backend[conf->old_yank], &error_abort);
+    qapi_free_ChardevReturn(ret);
+    chr = qemu_chr_find("chardev");
+    g_assert_nonnull(chr);
+
+    g_assert(is_yank_instance_registered() == conf->old_yank);
+
+    qemu_chr_wait_connected(chr, &error_abort);
+    qemu_chr_fe_init(&be, chr, &error_abort);
+    /* allow chardev-change */
+    qemu_chr_fe_set_handlers(&be, NULL, NULL,
+                             NULL, chardev_change, NULL, NULL, true);
+
+    if (conf->fail) {
+        g_setenv("QTEST_SILENT_ERRORS", "1", 1);
+        ret = qmp_chardev_change("chardev", &fail_backend[conf->new_yank],
+                                 NULL);
+        g_assert_null(ret);
+        g_assert(be.chr == chr);
+        g_assert(is_yank_instance_registered() == conf->old_yank);
+        g_unsetenv("QTEST_SILENT_ERRORS");
+    } else {
+        ret = qmp_chardev_change("chardev", &backend[conf->new_yank],
+                                 &error_abort);
+        g_assert_nonnull(ret);
+        g_assert(be.chr != chr);
+        g_assert(is_yank_instance_registered() == conf->new_yank);
+    }
+
+    object_unparent(OBJECT(be.chr));
+    object_unref(OBJECT(ioc));
+    qapi_free_ChardevReturn(ret);
+}
+
+static SocketAddress tcpaddr = {
+    .type = SOCKET_ADDRESS_TYPE_INET,
+    .u.inet.host = (char *)"127.0.0.1",
+    .u.inet.port = (char *)"0",
+};
+
+int main(int argc, char **argv)
+{
+    bool has_ipv4, has_ipv6;
+
+    qemu_init_main_loop(&error_abort);
+    socket_init();
+
+    g_test_init(&argc, &argv, NULL);
+
+    if (socket_check_protocol_support(&has_ipv4, &has_ipv6) < 0) {
+        g_printerr("socket_check_protocol_support() failed\n");
+        goto end;
+    }
+
+    if (!has_ipv4) {
+        goto end;
+    }
+
+    module_call_init(MODULE_INIT_QOM);
+    qemu_add_opts(&qemu_chardev_opts);
+
+#define CHAR_CHANGE_TEST(name, _old_yank, _new_yank)                           \
+    do {                                                                       \
+        g_test_add_data_func("/yank/char_change/success/" # name,              \
+                             &(CharChangeTestConfig) { .addr = &tcpaddr,       \
+                                                       .old_yank = (_old_yank),\
+                                                       .new_yank = (_new_yank),\
+                                                       .fail = false },        \
+                             char_change_test);                                \
+        g_test_add_data_func("/yank/char_change/fail/" # name,                 \
+                             &(CharChangeTestConfig) { .addr = &tcpaddr,       \
+                                                       .old_yank = (_old_yank),\
+                                                       .new_yank = (_new_yank),\
+                                                       .fail = true },         \
+                             char_change_test);                                \
+    } while (0)
+
+    CHAR_CHANGE_TEST(to_yank, false, true);
+    CHAR_CHANGE_TEST(yank_to_yank, true, true);
+    CHAR_CHANGE_TEST(from_yank, true, false);
+
+end:
+    return g_test_run();
+}
--
2.30.2


[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 833 bytes --]

^ permalink raw reply related	[flat|nested] 6+ messages in thread

* [PATCH v2 3/5] chardev/char.c: Move object_property_try_add_child out of chardev_new
  2021-03-22 15:40 [PATCH v2 0/5] yank: Add chardev tests and fixes Lukas Straub
  2021-03-22 15:41 ` [PATCH v2 1/5] tests: Use the normal yank code instead of stubs in relevant tests Lukas Straub
  2021-03-22 15:41 ` [PATCH v2 2/5] tests: Add tests for yank with the chardev-change case Lukas Straub
@ 2021-03-22 15:41 ` Lukas Straub
  2021-03-22 15:41 ` [PATCH v2 4/5] chardev/char.c: Always pass id to chardev_new Lukas Straub
  2021-03-22 15:41 ` [PATCH v2 5/5] chardev: Fix yank with the chardev-change case Lukas Straub
  4 siblings, 0 replies; 6+ messages in thread
From: Lukas Straub @ 2021-03-22 15:41 UTC (permalink / raw)
  To: qemu-devel
  Cc: Laurent Vivier, Marc-Andre Lureau, Thomas Huth, Li Zhang, Paolo Bonzini

[-- Attachment #1: Type: text/plain, Size: 2844 bytes --]

Move object_property_try_add_child out of chardev_new into it's
callers. This is a preparation for the next patches to fix yank
with the chardev-change case.

Signed-off-by: Lukas Straub <lukasstraub2@web.de>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Tested-by: Li Zhang <li.zhang@cloud.ionos.com>
---
 chardev/char.c | 42 ++++++++++++++++++++++++------------------
 1 file changed, 24 insertions(+), 18 deletions(-)

diff --git a/chardev/char.c b/chardev/char.c
index 97cafd6849..1584865027 100644
--- a/chardev/char.c
+++ b/chardev/char.c
@@ -972,7 +972,9 @@ static Chardev *chardev_new(const char *id, const char *typename,

     qemu_char_open(chr, backend, &be_opened, &local_err);
     if (local_err) {
-        goto end;
+        error_propagate(errp, local_err);
+        object_unref(obj);
+        return NULL;
     }

     if (!chr->filename) {
@@ -982,22 +984,6 @@ static Chardev *chardev_new(const char *id, const char *typename,
         qemu_chr_be_event(chr, CHR_EVENT_OPENED);
     }

-    if (id) {
-        object_property_try_add_child(get_chardevs_root(), id, obj,
-                                      &local_err);
-        if (local_err) {
-            goto end;
-        }
-        object_unref(obj);
-    }
-
-end:
-    if (local_err) {
-        error_propagate(errp, local_err);
-        object_unref(obj);
-        return NULL;
-    }
-
     return chr;
 }

@@ -1006,6 +992,7 @@ Chardev *qemu_chardev_new(const char *id, const char *typename,
                           GMainContext *gcontext,
                           Error **errp)
 {
+    Chardev *chr;
     g_autofree char *genid = NULL;

     if (!id) {
@@ -1013,7 +1000,19 @@ Chardev *qemu_chardev_new(const char *id, const char *typename,
         id = genid;
     }

-    return chardev_new(id, typename, backend, gcontext, errp);
+    chr = chardev_new(id, typename, backend, gcontext, errp);
+    if (!chr) {
+        return NULL;
+    }
+
+    if (!object_property_try_add_child(get_chardevs_root(), id, OBJECT(chr),
+                                       errp)) {
+        object_unref(OBJECT(chr));
+        return NULL;
+    }
+    object_unref(OBJECT(chr));
+
+    return chr;
 }

 ChardevReturn *qmp_chardev_add(const char *id, ChardevBackend *backend,
@@ -1034,6 +1033,13 @@ ChardevReturn *qmp_chardev_add(const char *id, ChardevBackend *backend,
         return NULL;
     }

+    if (!object_property_try_add_child(get_chardevs_root(), id, OBJECT(chr),
+                                       errp)) {
+        object_unref(OBJECT(chr));
+        return NULL;
+    }
+    object_unref(OBJECT(chr));
+
     ret = g_new0(ChardevReturn, 1);
     if (CHARDEV_IS_PTY(chr)) {
         ret->pty = g_strdup(chr->filename + 4);
--
2.30.2


[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 833 bytes --]

^ permalink raw reply related	[flat|nested] 6+ messages in thread

* [PATCH v2 4/5] chardev/char.c: Always pass id to chardev_new
  2021-03-22 15:40 [PATCH v2 0/5] yank: Add chardev tests and fixes Lukas Straub
                   ` (2 preceding siblings ...)
  2021-03-22 15:41 ` [PATCH v2 3/5] chardev/char.c: Move object_property_try_add_child out of chardev_new Lukas Straub
@ 2021-03-22 15:41 ` Lukas Straub
  2021-03-22 15:41 ` [PATCH v2 5/5] chardev: Fix yank with the chardev-change case Lukas Straub
  4 siblings, 0 replies; 6+ messages in thread
From: Lukas Straub @ 2021-03-22 15:41 UTC (permalink / raw)
  To: qemu-devel
  Cc: Laurent Vivier, Marc-Andre Lureau, Thomas Huth, Li Zhang, Paolo Bonzini

[-- Attachment #1: Type: text/plain, Size: 1550 bytes --]

Always pass the id to chardev_new, since it is needed to register
the yank instance for the chardev. Also, after checking that
nothing calls chardev_new with id=NULL, assert() that id!=NULL.

This fixes a crash when using chardev-change to change a chardev
to chardev-socket, which attempts to register a yank instance.
This in turn tries to dereference the NULL-pointer.

Signed-off-by: Lukas Straub <lukasstraub2@web.de>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Tested-by: Li Zhang <li.zhang@cloud.ionos.com>
---
 chardev/char.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/chardev/char.c b/chardev/char.c
index 1584865027..ad416c0714 100644
--- a/chardev/char.c
+++ b/chardev/char.c
@@ -964,6 +964,7 @@ static Chardev *chardev_new(const char *id, const char *typename,
     bool be_opened = true;

     assert(g_str_has_prefix(typename, "chardev-"));
+    assert(id);

     obj = object_new(typename);
     chr = CHARDEV(obj);
@@ -1092,12 +1093,11 @@ ChardevReturn *qmp_chardev_change(const char *id, ChardevBackend *backend,
         return NULL;
     }

-    chr_new = chardev_new(NULL, object_class_get_name(OBJECT_CLASS(cc)),
+    chr_new = chardev_new(id, object_class_get_name(OBJECT_CLASS(cc)),
                           backend, chr->gcontext, errp);
     if (!chr_new) {
         return NULL;
     }
-    chr_new->label = g_strdup(id);

     if (chr->be_open && !chr_new->be_open) {
         qemu_chr_be_event(chr, CHR_EVENT_CLOSED);
--
2.30.2


[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 833 bytes --]

^ permalink raw reply related	[flat|nested] 6+ messages in thread

* [PATCH v2 5/5] chardev: Fix yank with the chardev-change case
  2021-03-22 15:40 [PATCH v2 0/5] yank: Add chardev tests and fixes Lukas Straub
                   ` (3 preceding siblings ...)
  2021-03-22 15:41 ` [PATCH v2 4/5] chardev/char.c: Always pass id to chardev_new Lukas Straub
@ 2021-03-22 15:41 ` Lukas Straub
  4 siblings, 0 replies; 6+ messages in thread
From: Lukas Straub @ 2021-03-22 15:41 UTC (permalink / raw)
  To: qemu-devel
  Cc: Laurent Vivier, Marc-Andre Lureau, Thomas Huth, Li Zhang, Paolo Bonzini

[-- Attachment #1: Type: text/plain, Size: 7407 bytes --]

When changing from chardev-socket (which supports yank) to
chardev-socket again, it fails, because the new chardev attempts
to register a new yank instance. This in turn fails, as there
still is the yank instance from the current chardev. Also,
the old chardev shouldn't unregister the yank instance when it
is freed.

To fix this, now the new chardev only registers a yank instance if
the current chardev doesn't support yank and thus hasn't registered
one already. Also, when the old chardev is freed, it now only
unregisters the yank instance if the new chardev doesn't need it.

If the initialization of the new chardev fails, it still has
chr->handover_yank_instance set and won't unregister the yank
instance when it is freed.

s->registered_yank is always true here, as chardev-change only works
on user-visible chardevs and those are guraranteed to register a
yank instance as they are initialized via
chardev_new()
 qemu_char_open()
  cc->open() (qmp_chardev_open_socket()).

Signed-off-by: Lukas Straub <lukasstraub2@web.de>
Tested-by: Li Zhang <li.zhang@cloud.ionos.com>
---
 chardev/char-socket.c  | 20 +++++++++++++++++---
 chardev/char.c         | 35 ++++++++++++++++++++++++++++-------
 include/chardev/char.h |  3 +++
 3 files changed, 48 insertions(+), 10 deletions(-)

diff --git a/chardev/char-socket.c b/chardev/char-socket.c
index c8bced76b7..0cbe91f002 100644
--- a/chardev/char-socket.c
+++ b/chardev/char-socket.c
@@ -1119,7 +1119,13 @@ static void char_socket_finalize(Object *obj)
     }
     g_free(s->tls_authz);
     if (s->registered_yank) {
-        yank_unregister_instance(CHARDEV_YANK_INSTANCE(chr->label));
+        /*
+         * In the chardev-change special-case, we shouldn't unregister the yank
+         * instance, as it still may be needed.
+         */
+        if (!chr->handover_yank_instance) {
+            yank_unregister_instance(CHARDEV_YANK_INSTANCE(chr->label));
+        }
     }

     qemu_chr_be_event(chr, CHR_EVENT_CLOSED);
@@ -1421,8 +1427,14 @@ static void qmp_chardev_open_socket(Chardev *chr,
         qemu_chr_set_feature(chr, QEMU_CHAR_FEATURE_FD_PASS);
     }

-    if (!yank_register_instance(CHARDEV_YANK_INSTANCE(chr->label), errp)) {
-        return;
+    /*
+     * In the chardev-change special-case, we shouldn't register a new yank
+     * instance, as there already may be one.
+     */
+    if (!chr->handover_yank_instance) {
+        if (!yank_register_instance(CHARDEV_YANK_INSTANCE(chr->label), errp)) {
+            return;
+        }
     }
     s->registered_yank = true;

@@ -1564,6 +1576,8 @@ static void char_socket_class_init(ObjectClass *oc, void *data)
 {
     ChardevClass *cc = CHARDEV_CLASS(oc);

+    cc->supports_yank = true;
+
     cc->parse = qemu_chr_parse_socket;
     cc->open = qmp_chardev_open_socket;
     cc->chr_wait_connected = tcp_chr_wait_connected;
diff --git a/chardev/char.c b/chardev/char.c
index ad416c0714..9d8ec81a73 100644
--- a/chardev/char.c
+++ b/chardev/char.c
@@ -39,6 +39,7 @@
 #include "qemu/option.h"
 #include "qemu/id.h"
 #include "qemu/coroutine.h"
+#include "qemu/yank.h"

 #include "chardev-internal.h"

@@ -266,6 +267,7 @@ static void char_init(Object *obj)
 {
     Chardev *chr = CHARDEV(obj);

+    chr->handover_yank_instance = false;
     chr->logfd = -1;
     qemu_mutex_init(&chr->chr_write_lock);

@@ -956,6 +958,7 @@ void qemu_chr_set_feature(Chardev *chr,
 static Chardev *chardev_new(const char *id, const char *typename,
                             ChardevBackend *backend,
                             GMainContext *gcontext,
+                            bool handover_yank_instance,
                             Error **errp)
 {
     Object *obj;
@@ -968,6 +971,7 @@ static Chardev *chardev_new(const char *id, const char *typename,

     obj = object_new(typename);
     chr = CHARDEV(obj);
+    chr->handover_yank_instance = handover_yank_instance;
     chr->label = g_strdup(id);
     chr->gcontext = gcontext;

@@ -1001,7 +1005,7 @@ Chardev *qemu_chardev_new(const char *id, const char *typename,
         id = genid;
     }

-    chr = chardev_new(id, typename, backend, gcontext, errp);
+    chr = chardev_new(id, typename, backend, gcontext, false, errp);
     if (!chr) {
         return NULL;
     }
@@ -1029,7 +1033,7 @@ ChardevReturn *qmp_chardev_add(const char *id, ChardevBackend *backend,
     }

     chr = chardev_new(id, object_class_get_name(OBJECT_CLASS(cc)),
-                      backend, NULL, errp);
+                      backend, NULL, false, errp);
     if (!chr) {
         return NULL;
     }
@@ -1054,9 +1058,10 @@ ChardevReturn *qmp_chardev_change(const char *id, ChardevBackend *backend,
                                   Error **errp)
 {
     CharBackend *be;
-    const ChardevClass *cc;
+    const ChardevClass *cc, *cc_new;
     Chardev *chr, *chr_new;
     bool closed_sent = false;
+    bool handover_yank_instance;
     ChardevReturn *ret;

     chr = qemu_chr_find(id);
@@ -1088,13 +1093,20 @@ ChardevReturn *qmp_chardev_change(const char *id, ChardevBackend *backend,
         return NULL;
     }

-    cc = char_get_class(ChardevBackendKind_str(backend->type), errp);
-    if (!cc) {
+    cc = CHARDEV_GET_CLASS(chr);
+    cc_new = char_get_class(ChardevBackendKind_str(backend->type), errp);
+    if (!cc_new) {
         return NULL;
     }

-    chr_new = chardev_new(id, object_class_get_name(OBJECT_CLASS(cc)),
-                          backend, chr->gcontext, errp);
+    /*
+     * The new chardev should not register a yank instance if the current
+     * chardev has registered one already.
+     */
+    handover_yank_instance = cc->supports_yank && cc_new->supports_yank;
+
+    chr_new = chardev_new(id, object_class_get_name(OBJECT_CLASS(cc_new)),
+                          backend, chr->gcontext, handover_yank_instance, errp);
     if (!chr_new) {
         return NULL;
     }
@@ -1118,6 +1130,15 @@ ChardevReturn *qmp_chardev_change(const char *id, ChardevBackend *backend,
         return NULL;
     }

+    /* change successfull, clean up */
+    chr_new->handover_yank_instance = false;
+
+    /*
+     * When the old chardev is freed, it should not unregister the yank
+     * instance if the new chardev needs it.
+     */
+    chr->handover_yank_instance = handover_yank_instance;
+
     object_unparent(OBJECT(chr));
     object_property_add_child(get_chardevs_root(), chr_new->label,
                               OBJECT(chr_new));
diff --git a/include/chardev/char.h b/include/chardev/char.h
index 4181a2784a..7c0444f90d 100644
--- a/include/chardev/char.h
+++ b/include/chardev/char.h
@@ -65,6 +65,8 @@ struct Chardev {
     char *filename;
     int logfd;
     int be_open;
+    /* used to coordinate the chardev-change special-case: */
+    bool handover_yank_instance;
     GSource *gsource;
     GMainContext *gcontext;
     DECLARE_BITMAP(features, QEMU_CHAR_FEATURE_LAST);
@@ -251,6 +253,7 @@ struct ChardevClass {
     ObjectClass parent_class;

     bool internal; /* TODO: eventually use TYPE_USER_CREATABLE */
+    bool supports_yank;
     void (*parse)(QemuOpts *opts, ChardevBackend *backend, Error **errp);

     void (*open)(Chardev *chr, ChardevBackend *backend,
--
2.30.2

[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 833 bytes --]

^ permalink raw reply related	[flat|nested] 6+ messages in thread

end of thread, other threads:[~2021-03-22 15:49 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-03-22 15:40 [PATCH v2 0/5] yank: Add chardev tests and fixes Lukas Straub
2021-03-22 15:41 ` [PATCH v2 1/5] tests: Use the normal yank code instead of stubs in relevant tests Lukas Straub
2021-03-22 15:41 ` [PATCH v2 2/5] tests: Add tests for yank with the chardev-change case Lukas Straub
2021-03-22 15:41 ` [PATCH v2 3/5] chardev/char.c: Move object_property_try_add_child out of chardev_new Lukas Straub
2021-03-22 15:41 ` [PATCH v2 4/5] chardev/char.c: Always pass id to chardev_new Lukas Straub
2021-03-22 15:41 ` [PATCH v2 5/5] chardev: Fix yank with the chardev-change case Lukas Straub

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).