On Thu, Apr 18, 2024 at 01:13:29AM +0300, Vladimir Sementsov-Ogievskiy wrote:
> We do set MIGRATION_FAILED state, but don't give a chance to
> orchestrator to query migration state and get the error.
>
> Let's report an error through QAPI like we do on outgoing migration.
>
> migration-test is updated correspondingly.
>
> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsement...@yandex-team.ru>
> ---
>
> Doubt: is exiting on failure a contract? Will this commit break
> something in Libvirt? Finally, could we just change the logic, or I need
> and additional migration-parameter for new behavior?
There's a decent risk that this could break apps, whether
libvirt or something else, especially if the app is just
launching QEMU with '-incoming URI', rather than using
'-incoming defer' and then explicitly using QMP to start the
incoming migration.
I'd say that with '-incoming defer' we should *not* exit on
migration error, because that arg implies the app explicitly
wants to be using QMP to control migration.
With the legacy '-incoming URI' it is probably best to keep
exit on error, as that's comparatively more likely to be used
in adhoc scenarios where the app/user is ignoring QMP on the
dst side.
None the less, I think we need to check how libvirt behaves
with this patch to be sure of no surprises.
>
> migration/migration.c | 22 +++++++---------------
> tests/qtest/migration-helpers.c | 13 ++++++++++---
> tests/qtest/migration-helpers.h | 3 ++-
> tests/qtest/migration-test.c | 14 +++++++-------
> 4 files changed, 26 insertions(+), 26 deletions(-)
>
> diff --git a/migration/migration.c b/migration/migration.c
> index 86bf76e925..3c203e767d 100644
> --- a/migration/migration.c
> +++ b/migration/migration.c
> @@ -738,11 +738,12 @@ process_incoming_migration_co(void *opaque)
> MigrationIncomingState *mis = migration_incoming_get_current();
> PostcopyState ps;
> int ret;
> + Error *local_err = NULL;
>
> assert(mis->from_src_file);
>
> if (compress_threads_load_setup(mis->from_src_file)) {
> - error_report("Failed to setup decompress threads");
> + error_setg(&local_err, "Failed to setup decompress threads");
> goto fail;
> }
>
> @@ -779,32 +780,23 @@ process_incoming_migration_co(void *opaque)
> }
>
> if (ret < 0) {
> - MigrationState *s = migrate_get_current();
> -
> - if (migrate_has_error(s)) {
> - WITH_QEMU_LOCK_GUARD(&s->error_mutex) {
> - error_report_err(s->error);
> - }
> - }
> - error_report("load of migration failed: %s", strerror(-ret));
> + error_setg(&local_err, "load of migration failed: %s",
> strerror(-ret));
> goto fail;
> }
>
> if (colo_incoming_co() < 0) {
> + error_setg(&local_err, "colo incoming failed");
> goto fail;
> }
>
> migration_bh_schedule(process_incoming_migration_bh, mis);
> return;
> fail:
> + migrate_set_error(migrate_get_current(), local_err);
> + error_report_err(local_err);
> migrate_set_state(&mis->state, MIGRATION_STATUS_ACTIVE,
> MIGRATION_STATUS_FAILED);
> - qemu_fclose(mis->from_src_file);
> -
> - multifd_recv_cleanup();
> - compress_threads_load_cleanup();
> -
> - exit(EXIT_FAILURE);
> + migration_incoming_state_destroy();
> }
>
> /**
> diff --git a/tests/qtest/migration-helpers.c b/tests/qtest/migration-helpers.c
> index e451dbdbed..91c13bd566 100644
> --- a/tests/qtest/migration-helpers.c
> +++ b/tests/qtest/migration-helpers.c
> @@ -211,7 +211,8 @@ void wait_for_migration_complete(QTestState *who)
> wait_for_migration_status(who, "completed", NULL);
> }
>
> -void wait_for_migration_fail(QTestState *from, bool allow_active)
> +void wait_for_migration_fail(QTestState *from, bool allow_active,
> + bool is_incoming)
> {
> g_test_timer_start();
> QDict *rsp_return;
> @@ -236,8 +237,14 @@ void wait_for_migration_fail(QTestState *from, bool
> allow_active)
> /* Is the machine currently running? */
> rsp_return = qtest_qmp_assert_success_ref(from,
> "{ 'execute': 'query-status'
> }");
> - g_assert(qdict_haskey(rsp_return, "running"));
> - g_assert(qdict_get_bool(rsp_return, "running"));
> + if (is_incoming) {
> + if (qdict_haskey(rsp_return, "running")) {
> + g_assert(!qdict_get_bool(rsp_return, "running"));
> + }
> + } else {
> + g_assert(qdict_haskey(rsp_return, "running"));
> + g_assert(qdict_get_bool(rsp_return, "running"));
> + }
> qobject_unref(rsp_return);
> }
>
> diff --git a/tests/qtest/migration-helpers.h b/tests/qtest/migration-helpers.h
> index 3bf7ded1b9..7bd07059ae 100644
> --- a/tests/qtest/migration-helpers.h
> +++ b/tests/qtest/migration-helpers.h
> @@ -46,7 +46,8 @@ void wait_for_migration_status(QTestState *who,
>
> void wait_for_migration_complete(QTestState *who);
>
> -void wait_for_migration_fail(QTestState *from, bool allow_active);
> +void wait_for_migration_fail(QTestState *from, bool allow_active,
> + bool is_incoming);
>
> char *find_common_machine_version(const char *mtype, const char *var1,
> const char *var2);
> diff --git a/tests/qtest/migration-test.c b/tests/qtest/migration-test.c
> index 1d2cee87ea..e00b755f05 100644
> --- a/tests/qtest/migration-test.c
> +++ b/tests/qtest/migration-test.c
> @@ -1670,7 +1670,7 @@ static void test_baddest(void)
> return;
> }
> migrate_qmp(from, "tcp:127.0.0.1:0", "{}");
> - wait_for_migration_fail(from, false);
> + wait_for_migration_fail(from, false, false);
> test_migrate_end(from, to, false);
> }
>
> @@ -1781,10 +1781,10 @@ static void test_precopy_common(MigrateCommon *args)
>
> if (args->result != MIG_TEST_SUCCEED) {
> bool allow_active = args->result == MIG_TEST_FAIL;
> - wait_for_migration_fail(from, allow_active);
> + wait_for_migration_fail(from, allow_active, false);
>
> if (args->result == MIG_TEST_FAIL_DEST_QUIT_ERR) {
> - qtest_set_expected_status(to, EXIT_FAILURE);
> + wait_for_migration_fail(to, true, true);
> }
> } else {
> if (args->live) {
> @@ -2571,8 +2571,8 @@ static void do_test_validate_uuid(MigrateStart *args,
> bool should_fail)
> migrate_qmp(from, uri, "{}");
>
> if (should_fail) {
> - qtest_set_expected_status(to, EXIT_FAILURE);
> - wait_for_migration_fail(from, true);
> + wait_for_migration_fail(to, true, true);
> + wait_for_migration_fail(from, true, false);
> } else {
> wait_for_migration_complete(from);
> }
> @@ -3047,8 +3047,8 @@ static void test_multifd_tcp_cancel(void)
> migrate_cancel(from);
>
> /* Make sure QEMU process "to" exited */
> - qtest_set_expected_status(to, EXIT_FAILURE);
> - qtest_wait_qemu(to);
> + wait_for_migration_fail(to, true, true);
> + qtest_quit(to);
>
> args = (MigrateStart){
> .only_target = true,
> --
> 2.34.1
>
>
With regards,
Daniel
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