[PATCH v3 0/6] migration: Test the new "file:" migration

[PATCH v3 0/6] migration: Test the new "file:" migration

[Fabiano Rosas]

Based-on:
[PATCH V4 0/2] migration file URI
https://lore.kernel.org/r/1688135108-316997-1-git-send-email-steven.sistare@oracle.com

Since v2:

- removed the extra setup event. Libvirt has been enabling events for
  a long time, it should be safe

- fixed small issues pointed out by Peter (leaking memory, mmap args)

- stopped looking at the error string in the QMP error test

- skipped the check for zeroes on non-linux platforms

CI run: https://gitlab.com/farosas/qemu/-/pipelines/917665246

v2:
https://lore.kernel.org/r/20230628165542.17214-1-farosas@suse.de

- added the force-emit-setup-event property
- added verification that the skipped region is empty

CI run: https://gitlab.com/farosas/qemu/-/pipelines/914915941

v1:
https://lore.kernel.org/r/20230626182210.8792-1-farosas@suse.de

Here's the test for the file: migration.

I hit an issue with the setting of migration status. If we call
query-migrate too soon after migrate-incoming, the query returns an
empty response because we're not setting the MIGRATION_STATUS_SETUP in
the incoming path. We just send the event, but never actually change
state.

Aside from the fix, there's some tidying up to avoid duplicating too
much code in the tests.

Thanks

CI run: https://gitlab.com/farosas/qemu/-/pipelines/912226554

Fabiano Rosas (6):
  tests/qtest: migration: Expose migrate_set_capability
  tests/qtest: migration: Add migrate_incoming_qmp helper
  tests/qtest: migration: Use migrate_incoming_qmp where appropriate
  migration: Set migration status early in incoming side
  tests/qtest: migration: Add support for negative testing of
    qmp_migrate
  tests/qtest: migration-test: Add tests for file-based migration

 migration/migration.c             |   7 +-
 tests/qtest/libqtest.c            |  33 +++++++
 tests/qtest/libqtest.h            |  28 ++++++
 tests/qtest/meson.build           |   1 +
 tests/qtest/migration-helpers.c   |  60 +++++++++++++
 tests/qtest/migration-helpers.h   |  10 +++
 tests/qtest/migration-test.c      | 138 +++++++++++++++++++++++++-----
 tests/qtest/virtio-net-failover.c |  77 ++---------------
 8 files changed, 261 insertions(+), 93 deletions(-)

-- 
2.35.3

[PATCH v3 1/6] tests/qtest: migration: Expose migrate_set_capability

[Fabiano Rosas]

The following patch will make use of this function from within
migrate-helpers.c, so move it there.

Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
---
 tests/qtest/migration-helpers.c | 11 +++++++++++
 tests/qtest/migration-helpers.h |  3 +++
 tests/qtest/migration-test.c    | 11 -----------
 3 files changed, 14 insertions(+), 11 deletions(-)

diff --git a/tests/qtest/migration-helpers.c b/tests/qtest/migration-helpers.c
index be00c52d00..2df198c99e 100644
--- a/tests/qtest/migration-helpers.c
+++ b/tests/qtest/migration-helpers.c
@@ -70,6 +70,17 @@ void migrate_qmp(QTestState *who, const char *uri, const char *fmt, ...)
                              "{ 'execute': 'migrate', 'arguments': %p}", args);
 }
 
+void migrate_set_capability(QTestState *who, const char *capability,
+                            bool value)
+{
+    qtest_qmp_assert_success(who,
+                             "{ 'execute': 'migrate-set-capabilities',"
+                             "'arguments': { "
+                             "'capabilities': [ { "
+                             "'capability': %s, 'state': %i } ] } }",
+                             capability, value);
+}
+
 /*
  * Note: caller is responsible to free the returned object via
  * qobject_unref() after use
diff --git a/tests/qtest/migration-helpers.h b/tests/qtest/migration-helpers.h
index 009e250e90..484d7c960f 100644
--- a/tests/qtest/migration-helpers.h
+++ b/tests/qtest/migration-helpers.h
@@ -23,6 +23,9 @@ bool migrate_watch_for_resume(QTestState *who, const char *name,
 G_GNUC_PRINTF(3, 4)
 void migrate_qmp(QTestState *who, const char *uri, const char *fmt, ...);
 
+void migrate_set_capability(QTestState *who, const char *capability,
+                            bool value);
+
 QDict *migrate_query(QTestState *who);
 QDict *migrate_query_not_failed(QTestState *who);
 
diff --git a/tests/qtest/migration-test.c b/tests/qtest/migration-test.c
index 18bcfc04a6..df17bf431f 100644
--- a/tests/qtest/migration-test.c
+++ b/tests/qtest/migration-test.c
@@ -472,17 +472,6 @@ static void migrate_cancel(QTestState *who)
     qtest_qmp_assert_success(who, "{ 'execute': 'migrate_cancel' }");
 }
 
-static void migrate_set_capability(QTestState *who, const char *capability,
-                                   bool value)
-{
-    qtest_qmp_assert_success(who,
-                             "{ 'execute': 'migrate-set-capabilities',"
-                             "'arguments': { "
-                             "'capabilities': [ { "
-                             "'capability': %s, 'state': %i } ] } }",
-                             capability, value);
-}
-
 static void migrate_postcopy_start(QTestState *from, QTestState *to)
 {
     qtest_qmp_assert_success(from, "{ 'execute': 'migrate-start-postcopy' }");
-- 
2.35.3

[PATCH v3 2/6] tests/qtest: migration: Add migrate_incoming_qmp helper

[Fabiano Rosas]

file-based migration requires the target to initiate its migration after
the source has finished writing out the data in the file. Currently
there's no easy way to initiate 'migrate-incoming', allow this by
introducing migrate_incoming_qmp helper, similarly to migrate_qmp.

Also make sure migration events are enabled and wait for the incoming
migration to start before returning. This avoid a race when querying
the migration status too soon after issuing the command.

Signed-off-by: Fabiano Rosas <farosas@suse.de>
---
 tests/qtest/migration-helpers.c | 29 +++++++++++++++++++++++++++++
 tests/qtest/migration-helpers.h |  4 ++++
 2 files changed, 33 insertions(+)

diff --git a/tests/qtest/migration-helpers.c b/tests/qtest/migration-helpers.c
index 2df198c99e..08f5ee1179 100644
--- a/tests/qtest/migration-helpers.c
+++ b/tests/qtest/migration-helpers.c
@@ -81,6 +81,35 @@ void migrate_set_capability(QTestState *who, const char *capability,
                              capability, value);
 }
 
+void migrate_incoming_qmp(QTestState *to, const char *uri, const char *fmt, ...)
+{
+    va_list ap;
+    QDict *args, *rsp, *data;
+
+    va_start(ap, fmt);
+    args = qdict_from_vjsonf_nofail(fmt, ap);
+    va_end(ap);
+
+    g_assert(!qdict_haskey(args, "uri"));
+    qdict_put_str(args, "uri", uri);
+
+    migrate_set_capability(to, "events", true);
+
+    rsp = qtest_qmp(to, "{ 'execute': 'migrate-incoming', 'arguments': %p}",
+                    args);
+    g_assert(qdict_haskey(rsp, "return"));
+    qobject_unref(rsp);
+
+    rsp = qtest_qmp_eventwait_ref(to, "MIGRATION");
+    g_assert(qdict_haskey(rsp, "data"));
+
+    data = qdict_get_qdict(rsp, "data");
+    g_assert(qdict_haskey(data, "status"));
+    g_assert_cmpstr(qdict_get_str(data, "status"), ==, "setup");
+
+    qobject_unref(rsp);
+}
+
 /*
  * Note: caller is responsible to free the returned object via
  * qobject_unref() after use
diff --git a/tests/qtest/migration-helpers.h b/tests/qtest/migration-helpers.h
index 484d7c960f..57d295a4fe 100644
--- a/tests/qtest/migration-helpers.h
+++ b/tests/qtest/migration-helpers.h
@@ -23,6 +23,10 @@ bool migrate_watch_for_resume(QTestState *who, const char *name,
 G_GNUC_PRINTF(3, 4)
 void migrate_qmp(QTestState *who, const char *uri, const char *fmt, ...);
 
+G_GNUC_PRINTF(3, 4)
+void migrate_incoming_qmp(QTestState *who, const char *uri,
+                          const char *fmt, ...);
+
 void migrate_set_capability(QTestState *who, const char *capability,
                             bool value);
 
-- 
2.35.3

[PATCH v3 3/6] tests/qtest: migration: Use migrate_incoming_qmp where appropriate

[Fabiano Rosas]

Use the new migrate_incoming_qmp helper in the places that currently
open-code calling migrate-incoming.

Signed-off-by: Fabiano Rosas <farosas@suse.de>
Reviewed-by: Juan Quintela <quintela@redhat.com>
---
 tests/qtest/meson.build           |  1 +
 tests/qtest/migration-test.c      | 12 ++---
 tests/qtest/virtio-net-failover.c | 77 ++++---------------------------
 3 files changed, 14 insertions(+), 76 deletions(-)

diff --git a/tests/qtest/meson.build b/tests/qtest/meson.build
index 74630f6672..292d7d713f 100644
--- a/tests/qtest/meson.build
+++ b/tests/qtest/meson.build
@@ -313,6 +313,7 @@ qtests = {
   'tpm-tis-i2c-test': [io, tpmemu_files, 'qtest_aspeed.c'],
   'tpm-tis-device-swtpm-test': [io, tpmemu_files, 'tpm-tis-util.c'],
   'tpm-tis-device-test': [io, tpmemu_files, 'tpm-tis-util.c'],
+  'virtio-net-failover': files('migration-helpers.c'),
   'vmgenid-test': files('boot-sector.c', 'acpi-utils.c'),
   'netdev-socket': files('netdev-socket.c', '../unit/socket-helpers.c'),
 }
diff --git a/tests/qtest/migration-test.c b/tests/qtest/migration-test.c
index df17bf431f..c4140ac3f1 100644
--- a/tests/qtest/migration-test.c
+++ b/tests/qtest/migration-test.c
@@ -1846,8 +1846,7 @@ static void *test_migrate_fd_start_hook(QTestState *from,
     close(pair[0]);
 
     /* Start incoming migration from the 1st socket */
-    qtest_qmp_assert_success(to, "{ 'execute': 'migrate-incoming',"
-                             "  'arguments': { 'uri': 'fd:fd-mig' }}");
+    migrate_incoming_qmp(to, "fd:fd-mig", "{}");
 
     /* Send the 2nd socket to the target */
     qtest_qmp_fds_assert_success(from, &pair[1], 1,
@@ -2069,8 +2068,7 @@ test_migrate_precopy_tcp_multifd_start_common(QTestState *from,
     migrate_set_capability(to, "multifd", true);
 
     /* Start incoming migration from the 1st socket */
-    qtest_qmp_assert_success(to, "{ 'execute': 'migrate-incoming',"
-                             "  'arguments': { 'uri': 'tcp:127.0.0.1:0' }}");
+    migrate_incoming_qmp(to, "tcp:127.0.0.1:0", "{}");
 
     return NULL;
 }
@@ -2322,8 +2320,7 @@ static void test_multifd_tcp_cancel(void)
     migrate_set_capability(to, "multifd", true);
 
     /* Start incoming migration from the 1st socket */
-    qtest_qmp_assert_success(to, "{ 'execute': 'migrate-incoming',"
-                             "  'arguments': { 'uri': 'tcp:127.0.0.1:0' }}");
+    migrate_incoming_qmp(to, "tcp:127.0.0.1:0", "{}");
 
     /* Wait for the first serial output from the source */
     wait_for_serial("src_serial");
@@ -2353,8 +2350,7 @@ static void test_multifd_tcp_cancel(void)
     migrate_set_capability(to2, "multifd", true);
 
     /* Start incoming migration from the 1st socket */
-    qtest_qmp_assert_success(to2, "{ 'execute': 'migrate-incoming',"
-                             "  'arguments': { 'uri': 'tcp:127.0.0.1:0' }}");
+    migrate_incoming_qmp(to2, "tcp:127.0.0.1:0", "{}");
 
     g_free(uri);
     uri = migrate_get_socket_address(to2, "socket-address");
diff --git a/tests/qtest/virtio-net-failover.c b/tests/qtest/virtio-net-failover.c
index 4a809590bf..0d40bc1f2d 100644
--- a/tests/qtest/virtio-net-failover.c
+++ b/tests/qtest/virtio-net-failover.c
@@ -11,6 +11,7 @@
 #include "libqtest.h"
 #include "libqos/pci.h"
 #include "libqos/pci-pc.h"
+#include "migration-helpers.h"
 #include "qapi/qmp/qdict.h"
 #include "qapi/qmp/qlist.h"
 #include "qapi/qmp/qjson.h"
@@ -736,26 +737,10 @@ static void test_migrate_out(gconstpointer opaque)
     machine_stop(qts);
 }
 
-static QDict *get_migration_event(QTestState *qts)
-{
-    QDict *resp;
-    QDict *data;
-
-    resp = qtest_qmp_eventwait_ref(qts, "MIGRATION");
-    g_assert(qdict_haskey(resp, "data"));
-
-    data = qdict_get_qdict(resp, "data");
-    g_assert(qdict_haskey(data, "status"));
-    qobject_ref(data);
-    qobject_unref(resp);
-
-    return data;
-}
-
 static void test_migrate_in(gconstpointer opaque)
 {
     QTestState *qts;
-    QDict *resp, *args, *ret;
+    QDict *resp, *ret;
     g_autofree gchar *uri = g_strdup_printf("exec: cat %s", (gchar *)opaque);
 
     qts = machine_start(BASE_MACHINE
@@ -787,18 +772,7 @@ static void test_migrate_in(gconstpointer opaque)
     check_one_card(qts, true, "standby0", MAC_STANDBY0);
     check_one_card(qts, false, "primary0", MAC_PRIMARY0);
 
-    args = qdict_from_jsonf_nofail("{}");
-    g_assert_nonnull(args);
-    qdict_put_str(args, "uri", uri);
-
-    resp = qtest_qmp(qts, "{ 'execute': 'migrate-incoming', 'arguments': %p}",
-                     args);
-    g_assert(qdict_haskey(resp, "return"));
-    qobject_unref(resp);
-
-    resp = get_migration_event(qts);
-    g_assert_cmpstr(qdict_get_str(resp, "status"), ==, "setup");
-    qobject_unref(resp);
+    migrate_incoming_qmp(qts, uri, "{}");
 
     resp = get_failover_negociated_event(qts);
     g_assert_cmpstr(qdict_get_str(resp, "device-id"), ==, "standby0");
@@ -888,7 +862,7 @@ static void test_off_migrate_out(gconstpointer opaque)
 static void test_off_migrate_in(gconstpointer opaque)
 {
     QTestState *qts;
-    QDict *resp, *args, *ret;
+    QDict *ret;
     g_autofree gchar *uri = g_strdup_printf("exec: cat %s", (gchar *)opaque);
 
     qts = machine_start(BASE_MACHINE
@@ -920,18 +894,7 @@ static void test_off_migrate_in(gconstpointer opaque)
     check_one_card(qts, true, "standby0", MAC_STANDBY0);
     check_one_card(qts, true, "primary0", MAC_PRIMARY0);
 
-    args = qdict_from_jsonf_nofail("{}");
-    g_assert_nonnull(args);
-    qdict_put_str(args, "uri", uri);
-
-    resp = qtest_qmp(qts, "{ 'execute': 'migrate-incoming', 'arguments': %p}",
-                     args);
-    g_assert(qdict_haskey(resp, "return"));
-    qobject_unref(resp);
-
-    resp = get_migration_event(qts);
-    g_assert_cmpstr(qdict_get_str(resp, "status"), ==, "setup");
-    qobject_unref(resp);
+    migrate_incoming_qmp(qts, uri, "{}");
 
     check_one_card(qts, true, "standby0", MAC_STANDBY0);
     check_one_card(qts, true, "primary0", MAC_PRIMARY0);
@@ -1026,7 +989,7 @@ static void test_guest_off_migrate_out(gconstpointer opaque)
 static void test_guest_off_migrate_in(gconstpointer opaque)
 {
     QTestState *qts;
-    QDict *resp, *args, *ret;
+    QDict *ret;
     g_autofree gchar *uri = g_strdup_printf("exec: cat %s", (gchar *)opaque);
 
     qts = machine_start(BASE_MACHINE
@@ -1058,18 +1021,7 @@ static void test_guest_off_migrate_in(gconstpointer opaque)
     check_one_card(qts, true, "standby0", MAC_STANDBY0);
     check_one_card(qts, false, "primary0", MAC_PRIMARY0);
 
-    args = qdict_from_jsonf_nofail("{}");
-    g_assert_nonnull(args);
-    qdict_put_str(args, "uri", uri);
-
-    resp = qtest_qmp(qts, "{ 'execute': 'migrate-incoming', 'arguments': %p}",
-                     args);
-    g_assert(qdict_haskey(resp, "return"));
-    qobject_unref(resp);
-
-    resp = get_migration_event(qts);
-    g_assert_cmpstr(qdict_get_str(resp, "status"), ==, "setup");
-    qobject_unref(resp);
+    migrate_incoming_qmp(qts, uri, "{}");
 
     check_one_card(qts, true, "standby0", MAC_STANDBY0);
     check_one_card(qts, false, "primary0", MAC_PRIMARY0);
@@ -1728,7 +1680,7 @@ static void test_multi_out(gconstpointer opaque)
 static void test_multi_in(gconstpointer opaque)
 {
     QTestState *qts;
-    QDict *resp, *args, *ret;
+    QDict *resp, *ret;
     g_autofree gchar *uri = g_strdup_printf("exec: cat %s", (gchar *)opaque);
 
     qts = machine_start(BASE_MACHINE
@@ -1794,18 +1746,7 @@ static void test_multi_in(gconstpointer opaque)
     check_one_card(qts, true, "standby1", MAC_STANDBY1);
     check_one_card(qts, false, "primary1", MAC_PRIMARY1);
 
-    args = qdict_from_jsonf_nofail("{}");
-    g_assert_nonnull(args);
-    qdict_put_str(args, "uri", uri);
-
-    resp = qtest_qmp(qts, "{ 'execute': 'migrate-incoming', 'arguments': %p}",
-                     args);
-    g_assert(qdict_haskey(resp, "return"));
-    qobject_unref(resp);
-
-    resp = get_migration_event(qts);
-    g_assert_cmpstr(qdict_get_str(resp, "status"), ==, "setup");
-    qobject_unref(resp);
+    migrate_incoming_qmp(qts, uri, "{}");
 
     resp = get_failover_negociated_event(qts);
     g_assert_cmpstr(qdict_get_str(resp, "device-id"), ==, "standby0");
-- 
2.35.3

[PATCH v3 4/6] migration: Set migration status early in incoming side

[Fabiano Rosas]

We are sending a migration event of MIGRATION_STATUS_SETUP at
qemu_start_incoming_migration but never actually setting the state.

This creates a window between qmp_migrate_incoming and
process_incoming_migration_co where the migration status is still
MIGRATION_STATUS_NONE. Calling query-migrate during this time will
return an empty response even though the incoming migration command
has already been issued.

Commit 7cf1fe6d68 ("migration: Add migration events on target side")
has added support to the 'events' capability to the incoming part of
migration, but chose to send the SETUP event without setting the
state. I'm assuming this was a mistake.

This introduces a change in behavior, any QMP client waiting for the
SETUP event will hang, unless it has previously enabled the 'events'
capability. Having the capability enabled is sufficient to continue to
receive the event.

Signed-off-by: Fabiano Rosas <farosas@suse.de>
---
 migration/migration.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/migration/migration.c b/migration/migration.c
index 92ad9f2470..f2d2782101 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -425,13 +425,16 @@ void migrate_add_address(SocketAddress *address)
 static void qemu_start_incoming_migration(const char *uri, Error **errp)
 {
     const char *p = NULL;
+    MigrationIncomingState *mis = migration_incoming_get_current();
 
     /* URI is not suitable for migration? */
     if (!migration_channels_and_uri_compatible(uri, errp)) {
         return;
     }
 
-    qapi_event_send_migration(MIGRATION_STATUS_SETUP);
+    migrate_set_state(&mis->state, MIGRATION_STATUS_NONE,
+                      MIGRATION_STATUS_SETUP);
+
     if (strstart(uri, "tcp:", &p) ||
         strstart(uri, "unix:", NULL) ||
         strstart(uri, "vsock:", NULL)) {
@@ -525,7 +528,7 @@ process_incoming_migration_co(void *opaque)
 
     mis->largest_page_size = qemu_ram_pagesize_largest();
     postcopy_state_set(POSTCOPY_INCOMING_NONE);
-    migrate_set_state(&mis->state, MIGRATION_STATUS_NONE,
+    migrate_set_state(&mis->state, MIGRATION_STATUS_SETUP,
                       MIGRATION_STATUS_ACTIVE);
 
     mis->loadvm_co = qemu_coroutine_self();
-- 
2.35.3

[PATCH v3 5/6] tests/qtest: migration: Add support for negative testing of qmp_migrate

[Fabiano Rosas]

There is currently no way to write a test for errors that happened in
qmp_migrate before the migration has started.

Add a version of qmp_migrate that ensures an error happens. To make
use of it a test needs to set MigrateCommon.result as
MIG_TEST_QMP_ERROR.

Signed-off-by: Fabiano Rosas <farosas@suse.de>
---
 tests/qtest/libqtest.c          | 33 +++++++++++++++++++++++++++++++++
 tests/qtest/libqtest.h          | 28 ++++++++++++++++++++++++++++
 tests/qtest/migration-helpers.c | 20 ++++++++++++++++++++
 tests/qtest/migration-helpers.h |  3 +++
 tests/qtest/migration-test.c    | 16 ++++++++++++----
 5 files changed, 96 insertions(+), 4 deletions(-)

diff --git a/tests/qtest/libqtest.c b/tests/qtest/libqtest.c
index 79152f0ec3..011ed255fa 100644
--- a/tests/qtest/libqtest.c
+++ b/tests/qtest/libqtest.c
@@ -1248,6 +1248,28 @@ void qtest_memset(QTestState *s, uint64_t addr, uint8_t pattern, size_t size)
     qtest_rsp(s);
 }
 
+QDict *qtest_vqmp_assert_failure_ref(QTestState *qts,
+                                     const char *fmt, va_list args)
+{
+    QDict *response;
+    QDict *ret;
+
+    response = qtest_vqmp(qts, fmt, args);
+
+    g_assert(response);
+    if (!qdict_haskey(response, "error")) {
+        g_autoptr(GString) s = qobject_to_json_pretty(QOBJECT(response), true);
+        g_test_message("%s", s->str);
+    }
+    g_assert(qdict_haskey(response, "error"));
+    g_assert(!qdict_haskey(response, "return"));
+    ret = qdict_get_qdict(response, "error");
+    qobject_ref(ret);
+    qobject_unref(response);
+
+    return ret;
+}
+
 QDict *qtest_vqmp_assert_success_ref(QTestState *qts,
                                      const char *fmt, va_list args)
 {
@@ -1310,6 +1332,17 @@ void qtest_vqmp_fds_assert_success(QTestState *qts, int *fds, size_t nfds,
 }
 #endif /* !_WIN32 */
 
+QDict *qtest_qmp_assert_failure_ref(QTestState *qts, const char *fmt, ...)
+{
+    QDict *response;
+    va_list ap;
+
+    va_start(ap, fmt);
+    response = qtest_vqmp_assert_failure_ref(qts, fmt, ap);
+    va_end(ap);
+    return response;
+}
+
 QDict *qtest_qmp_assert_success_ref(QTestState *qts, const char *fmt, ...)
 {
     QDict *response;
diff --git a/tests/qtest/libqtest.h b/tests/qtest/libqtest.h
index 913acc3d5c..7ef19ce3ff 100644
--- a/tests/qtest/libqtest.h
+++ b/tests/qtest/libqtest.h
@@ -799,6 +799,34 @@ void qtest_vqmp_fds_assert_success(QTestState *qts, int *fds, size_t nfds,
     G_GNUC_PRINTF(4, 0);
 #endif /* !_WIN32 */
 
+/**
+ * qtest_qmp_assert_failure_ref:
+ * @qts: QTestState instance to operate on
+ * @fmt: QMP message to send to qemu, formatted like
+ * qobject_from_jsonf_nofail().  See parse_interpolation() for what's
+ * supported after '%'.
+ *
+ * Sends a QMP message to QEMU, asserts that an 'error' key is present in
+ * the response, and returns the response.
+ */
+QDict *qtest_qmp_assert_failure_ref(QTestState *qts, const char *fmt, ...)
+    G_GNUC_PRINTF(2, 3);
+
+/**
+ * qtest_vqmp_assert_failure_ref:
+ * @qts: QTestState instance to operate on
+ * @fmt: QMP message to send to qemu, formatted like
+ * qobject_from_jsonf_nofail().  See parse_interpolation() for what's
+ * supported after '%'.
+ * @args: variable arguments for @fmt
+ *
+ * Sends a QMP message to QEMU, asserts that an 'error' key is present in
+ * the response, and returns the response.
+ */
+QDict *qtest_vqmp_assert_failure_ref(QTestState *qts,
+                                     const char *fmt, va_list args)
+    G_GNUC_PRINTF(2, 0);
+
 /**
  * qtest_qmp_assert_success_ref:
  * @qts: QTestState instance to operate on
diff --git a/tests/qtest/migration-helpers.c b/tests/qtest/migration-helpers.c
index 08f5ee1179..0c185db450 100644
--- a/tests/qtest/migration-helpers.c
+++ b/tests/qtest/migration-helpers.c
@@ -49,6 +49,26 @@ bool migrate_watch_for_resume(QTestState *who, const char *name,
     return false;
 }
 
+void migrate_qmp_fail(QTestState *who, const char *uri, const char *fmt, ...)
+{
+    va_list ap;
+    QDict *args, *err;
+
+    va_start(ap, fmt);
+    args = qdict_from_vjsonf_nofail(fmt, ap);
+    va_end(ap);
+
+    g_assert(!qdict_haskey(args, "uri"));
+    qdict_put_str(args, "uri", uri);
+
+    err = qtest_qmp_assert_failure_ref(
+        who, "{ 'execute': 'migrate', 'arguments': %p}", args);
+
+    g_assert(qdict_haskey(err, "desc"));
+
+    qobject_unref(err);
+}
+
 /*
  * Send QMP command "migrate".
  * Arguments are built from @fmt... (formatted like
diff --git a/tests/qtest/migration-helpers.h b/tests/qtest/migration-helpers.h
index 57d295a4fe..4f51d0f8bc 100644
--- a/tests/qtest/migration-helpers.h
+++ b/tests/qtest/migration-helpers.h
@@ -27,6 +27,9 @@ G_GNUC_PRINTF(3, 4)
 void migrate_incoming_qmp(QTestState *who, const char *uri,
                           const char *fmt, ...);
 
+G_GNUC_PRINTF(3, 4)
+void migrate_qmp_fail(QTestState *who, const char *uri, const char *fmt, ...);
+
 void migrate_set_capability(QTestState *who, const char *capability,
                             bool value);
 
diff --git a/tests/qtest/migration-test.c b/tests/qtest/migration-test.c
index c4140ac3f1..2fdf6a115e 100644
--- a/tests/qtest/migration-test.c
+++ b/tests/qtest/migration-test.c
@@ -564,6 +564,8 @@ typedef struct {
         MIG_TEST_FAIL,
         /* This test should fail, dest qemu should fail with abnormal status */
         MIG_TEST_FAIL_DEST_QUIT_ERR,
+        /* The QMP command for this migration should fail with an error */
+        MIG_TEST_QMP_ERROR,
     } result;
 
     /* Optional: set number of migration passes to wait for, if live==true */
@@ -1379,6 +1381,7 @@ static void test_precopy_common(MigrateCommon *args)
 {
     QTestState *from, *to;
     void *data_hook = NULL;
+    g_autofree char *connect_uri = NULL;
 
     if (test_migrate_start(&from, &to, args->listen_uri, &args->start)) {
         return;
@@ -1419,13 +1422,17 @@ static void test_precopy_common(MigrateCommon *args)
     }
 
     if (!args->connect_uri) {
-        g_autofree char *local_connect_uri =
-            migrate_get_socket_address(to, "socket-address");
-        migrate_qmp(from, local_connect_uri, "{}");
+        connect_uri = migrate_get_socket_address(to, "socket-address");
     } else {
-        migrate_qmp(from, args->connect_uri, "{}");
+        connect_uri = g_strdup(args->connect_uri);
     }
 
+    if (args->result == MIG_TEST_QMP_ERROR) {
+        migrate_qmp_fail(from, connect_uri, "{}");
+        goto finish;
+    }
+
+    migrate_qmp(from, connect_uri, "{}");
 
     if (args->result != MIG_TEST_SUCCEED) {
         bool allow_active = args->result == MIG_TEST_FAIL;
@@ -1474,6 +1481,7 @@ static void test_precopy_common(MigrateCommon *args)
         wait_for_serial("dest_serial");
     }
 
+finish:
     if (args->finish_hook) {
         args->finish_hook(from, to, data_hook);
     }
-- 
2.35.3

[PATCH v3 6/6] tests/qtest: migration-test: Add tests for file-based migration

[Fabiano Rosas]

Add basic tests for file-based migration.

Signed-off-by: Fabiano Rosas <farosas@suse.de>
---
 tests/qtest/migration-test.c | 99 ++++++++++++++++++++++++++++++++++++
 1 file changed, 99 insertions(+)

diff --git a/tests/qtest/migration-test.c b/tests/qtest/migration-test.c
index 2fdf6a115e..a180f53b5a 100644
--- a/tests/qtest/migration-test.c
+++ b/tests/qtest/migration-test.c
@@ -52,6 +52,10 @@ static bool got_dst_resume;
  */
 #define DIRTYLIMIT_TOLERANCE_RANGE  25  /* MB/s */
 
+#define QEMU_VM_FILE_MAGIC 0x5145564d
+#define FILE_TEST_FILENAME "migfile"
+#define FILE_TEST_OFFSET 0x1000
+
 #if defined(__linux__)
 #include <sys/syscall.h>
 #include <sys/vfs.h>
@@ -762,6 +766,7 @@ static void test_migrate_end(QTestState *from, QTestState *to, bool test_dest)
     cleanup("migsocket");
     cleanup("src_serial");
     cleanup("dest_serial");
+    cleanup(FILE_TEST_FILENAME);
 }
 
 #ifdef CONFIG_GNUTLS
@@ -1459,11 +1464,28 @@ static void test_precopy_common(MigrateCommon *args)
              */
             wait_for_migration_complete(from);
 
+            /*
+             * For file based migration the target must begin its
+             * migration after the source has finished.
+             */
+            if (strstr(connect_uri, "file:")) {
+                migrate_incoming_qmp(to, connect_uri, "{}");
+            }
+
             if (!got_src_stop) {
                 qtest_qmp_eventwait(from, "STOP");
             }
         } else {
             wait_for_migration_complete(from);
+
+            /*
+             * For file based migration the target must begin its
+             * migration after the source has finished.
+             */
+            if (strstr(connect_uri, "file:")) {
+                migrate_incoming_qmp(to, connect_uri, "{}");
+            }
+
             /*
              * Must wait for dst to finish reading all incoming
              * data on the socket before issuing 'cont' otherwise
@@ -1681,6 +1703,75 @@ static void test_precopy_unix_compress_nowait(void)
     test_precopy_common(&args);
 }
 
+static void test_precopy_file(void)
+{
+    g_autofree char *uri = g_strdup_printf("file:%s/%s", tmpfs,
+                                           FILE_TEST_FILENAME);
+    MigrateCommon args = {
+        .connect_uri = uri,
+        .listen_uri = "defer",
+    };
+
+    test_precopy_common(&args);
+}
+
+static void file_offset_finish_hook(QTestState *from, QTestState *to, void *opaque)
+{
+#if defined(__linux__)
+    g_autofree char *path = g_strdup_printf("%s/%s", tmpfs, FILE_TEST_FILENAME);
+    size_t size = FILE_TEST_OFFSET + sizeof(QEMU_VM_FILE_MAGIC);
+    uintptr_t *addr, *p;
+    int fd;
+
+    fd = open(path, O_RDONLY);
+    g_assert(fd != -1);
+    addr = mmap(NULL, size, PROT_READ, MAP_SHARED, fd, 0);
+    g_assert(addr != MAP_FAILED);
+
+    /*
+     * Ensure the skipped offset contains zeros and the migration
+     * stream starts at the right place.
+     */
+    p = addr;
+    while (p < addr + FILE_TEST_OFFSET / sizeof(uintptr_t)) {
+        g_assert(*p == 0);
+        p++;
+    }
+    g_assert_cmpint(cpu_to_be32(*p), ==, QEMU_VM_FILE_MAGIC);
+
+    munmap(addr, size);
+    close(fd);
+#endif
+}
+
+static void test_precopy_file_offset(void)
+{
+    g_autofree char *uri = g_strdup_printf("file:%s/%s,offset=%d", tmpfs,
+                                           FILE_TEST_FILENAME,
+                                           FILE_TEST_OFFSET);
+    MigrateCommon args = {
+        .connect_uri = uri,
+        .listen_uri = "defer",
+        .finish_hook = file_offset_finish_hook,
+    };
+
+    test_precopy_common(&args);
+}
+
+static void test_precopy_file_offset_bad(void)
+{
+    /* using a value not supported by qemu_strtosz() */
+    g_autofree char *uri = g_strdup_printf("file:%s/migfile,offset=0x20M",
+                                           tmpfs);
+    MigrateCommon args = {
+        .connect_uri = uri,
+        .listen_uri = "defer",
+        .result = MIG_TEST_QMP_ERROR,
+    };
+
+    test_precopy_common(&args);
+}
+
 static void test_precopy_tcp_plain(void)
 {
     MigrateCommon args = {
@@ -2730,6 +2821,14 @@ int main(int argc, char **argv)
         qtest_add_func("/migration/precopy/unix/compress/nowait",
                        test_precopy_unix_compress_nowait);
     }
+
+    qtest_add_func("/migration/precopy/file",
+                   test_precopy_file);
+    qtest_add_func("/migration/precopy/file/offset",
+                   test_precopy_file_offset);
+    qtest_add_func("/migration/precopy/file/offset/bad",
+                   test_precopy_file_offset_bad);
+
 #ifdef CONFIG_GNUTLS
     qtest_add_func("/migration/precopy/unix/tls/psk",
                    test_precopy_unix_tls_psk);
-- 
2.35.3

Re: [PATCH v3 2/6] tests/qtest: migration: Add migrate_incoming_qmp helper

[Peter Xu]

On Fri, Jun 30, 2023 at 06:28:58PM -0300, Fabiano Rosas wrote:
> file-based migration requires the target to initiate its migration after
> the source has finished writing out the data in the file. Currently
> there's no easy way to initiate 'migrate-incoming', allow this by
> introducing migrate_incoming_qmp helper, similarly to migrate_qmp.
> 
> Also make sure migration events are enabled and wait for the incoming
> migration to start before returning. This avoid a race when querying
> the migration status too soon after issuing the command.
> 
> Signed-off-by: Fabiano Rosas <farosas@suse.de>

Reviewed-by: Peter Xu <peterx@redhat.com>

-- 
Peter Xu

Re: [PATCH v3 3/6] tests/qtest: migration: Use migrate_incoming_qmp where appropriate

[Peter Xu]

On Fri, Jun 30, 2023 at 06:28:59PM -0300, Fabiano Rosas wrote:
> Use the new migrate_incoming_qmp helper in the places that currently
> open-code calling migrate-incoming.
> 
> Signed-off-by: Fabiano Rosas <farosas@suse.de>
> Reviewed-by: Juan Quintela <quintela@redhat.com>

Reviewed-by: Peter Xu <peterx@redhat.com>

-- 
Peter Xu

Re: [PATCH v3 1/6] tests/qtest: migration: Expose migrate_set_capability

[Peter Xu]

On Fri, Jun 30, 2023 at 06:28:57PM -0300, Fabiano Rosas wrote:
> The following patch will make use of this function from within
> migrate-helpers.c, so move it there.
> 
> Reviewed-by: Juan Quintela <quintela@redhat.com>
> Reviewed-by: Thomas Huth <thuth@redhat.com>
> Signed-off-by: Fabiano Rosas <farosas@suse.de>

Reviewed-by: Peter Xu <peterx@redhat.com>

-- 
Peter Xu

Re: [PATCH v3 4/6] migration: Set migration status early in incoming side

[Peter Xu]

On Fri, Jun 30, 2023 at 06:29:00PM -0300, Fabiano Rosas wrote:
> We are sending a migration event of MIGRATION_STATUS_SETUP at
> qemu_start_incoming_migration but never actually setting the state.
> 
> This creates a window between qmp_migrate_incoming and
> process_incoming_migration_co where the migration status is still
> MIGRATION_STATUS_NONE. Calling query-migrate during this time will
> return an empty response even though the incoming migration command
> has already been issued.
> 
> Commit 7cf1fe6d68 ("migration: Add migration events on target side")
> has added support to the 'events' capability to the incoming part of
> migration, but chose to send the SETUP event without setting the
> state. I'm assuming this was a mistake.
> 
> This introduces a change in behavior, any QMP client waiting for the
> SETUP event will hang, unless it has previously enabled the 'events'
> capability. Having the capability enabled is sufficient to continue to
> receive the event.
> 
> Signed-off-by: Fabiano Rosas <farosas@suse.de>

Reviewed-by: Peter Xu <peterx@redhat.com>

-- 
Peter Xu

Re: [PATCH v3 6/6] tests/qtest: migration-test: Add tests for file-based migration

[Peter Xu]

On Fri, Jun 30, 2023 at 06:29:02PM -0300, Fabiano Rosas wrote:
> Add basic tests for file-based migration.
> 
> Signed-off-by: Fabiano Rosas <farosas@suse.de>

Reviewed-by: Peter Xu <peterx@redhat.com>

One trivial comment below:

> +static void test_precopy_file_offset_bad(void)
> +{
> +    /* using a value not supported by qemu_strtosz() */
> +    g_autofree char *uri = g_strdup_printf("file:%s/migfile,offset=0x20M",

Better reuse FILE_TEST_FILENAME.

> +                                           tmpfs);
> +    MigrateCommon args = {
> +        .connect_uri = uri,
> +        .listen_uri = "defer",
> +        .result = MIG_TEST_QMP_ERROR,
> +    };
> +
> +    test_precopy_common(&args);
> +}

-- 
Peter Xu

Re: [PATCH v3 5/6] tests/qtest: migration: Add support for negative testing of qmp_migrate

[Peter Xu]

On Fri, Jun 30, 2023 at 06:29:01PM -0300, Fabiano Rosas wrote:
> There is currently no way to write a test for errors that happened in
> qmp_migrate before the migration has started.
> 
> Add a version of qmp_migrate that ensures an error happens. To make
> use of it a test needs to set MigrateCommon.result as
> MIG_TEST_QMP_ERROR.
> 
> Signed-off-by: Fabiano Rosas <farosas@suse.de>

Reviewed-by: Peter Xu <peterx@redhat.com>

-- 
Peter Xu