On Wed, Mar 06, 2024 at 02:34:25PM +0100, Cédric Le Goater wrote: > This prepares ground for the changes coming next which add an Error** > argument to the .save_setup() handler. Callers of qemu_savevm_state_setup() > now handle the error and fail earlier setting the migration state from > MIGRATION_STATUS_SETUP to MIGRATION_STATUS_FAILED. > > In qemu_savevm_state(), move the cleanup to preserve the error > reported by .save_setup() handlers. > > Since the previous behavior was to ignore errors at this step of > migration, this change should be examined closely to check that > cleanups are still correctly done. > > Signed-off-by: Cédric Le Goater <c...@redhat.com> > --- > > Changes in v4: > > - Merged cleanup change in qemu_savevm_state() > > Changes in v3: > > - Set migration state to MIGRATION_STATUS_FAILED > - Fixed error handling to be done under lock in bg_migration_thread() > - Made sure an error is always set in case of failure in > qemu_savevm_state_setup() > > migration/savevm.h | 2 +- > migration/migration.c | 27 ++++++++++++++++++++++++--- > migration/savevm.c | 26 +++++++++++++++----------- > 3 files changed, 40 insertions(+), 15 deletions(-) > > diff --git a/migration/savevm.h b/migration/savevm.h > index > 74669733dd63a080b765866c703234a5c4939223..9ec96a995c93a42aad621595f0ed58596c532328 > 100644 > --- a/migration/savevm.h > +++ b/migration/savevm.h > @@ -32,7 +32,7 @@ > bool qemu_savevm_state_blocked(Error **errp); > void qemu_savevm_non_migratable_list(strList **reasons); > int qemu_savevm_state_prepare(Error **errp); > -void qemu_savevm_state_setup(QEMUFile *f); > +int qemu_savevm_state_setup(QEMUFile *f, Error **errp); > bool qemu_savevm_state_guest_unplug_pending(void); > int qemu_savevm_state_resume_prepare(MigrationState *s); > void qemu_savevm_state_header(QEMUFile *f); > diff --git a/migration/migration.c b/migration/migration.c > index > a49fcd53ee19df1ce0182bc99d7e064968f0317b..6d1544224e96f5edfe56939a9c8395d88ef29581 > 100644 > --- a/migration/migration.c > +++ b/migration/migration.c > @@ -3408,6 +3408,8 @@ static void *migration_thread(void *opaque) > int64_t setup_start = qemu_clock_get_ms(QEMU_CLOCK_HOST); > MigThrError thr_error; > bool urgent = false; > + Error *local_err = NULL; > + int ret; > > thread = migration_threads_add("live_migration", qemu_get_thread_id()); > > @@ -3451,9 +3453,17 @@ static void *migration_thread(void *opaque) > } > > bql_lock(); > - qemu_savevm_state_setup(s->to_dst_file); > + ret = qemu_savevm_state_setup(s->to_dst_file, &local_err); > bql_unlock(); > > + if (ret) { > + migrate_set_error(s, local_err); > + error_free(local_err); > + migrate_set_state(&s->state, MIGRATION_STATUS_SETUP, > + MIGRATION_STATUS_FAILED); > + goto out; > + }
There's a small indent issue, I can fix it. The bigger problem is I _think_ this will trigger a ci failure in the virtio-net-failover test: ▶ 121/464 ERROR:../tests/qtest/virtio-net-failover.c:1203:test_migrate_abort_wait_unplug: assertion failed (status == "cancelling"): ("cancelled" == "cancelling") ERROR 121/464 qemu:qtest+qtest-x86_64 / qtest-x86_64/virtio-net-failover ERROR 4.77s killed by signal 6 SIGABRT >>> PYTHON=/builds/peterx/qemu/build/pyvenv/bin/python3.8 >>> G_TEST_DBUS_DAEMON=/builds/peterx/qemu/tests/dbus-vmstate-daemon.sh >>> MALLOC_PERTURB_=161 QTEST_QEMU_IMG=./qemu-img >>> QTEST_QEMU_STORAGE_DAEMON_BINARY=./storage-daemon/qemu-storage-daemon >>> QTEST_QEMU_BINARY=./qemu-system-x86_64 >>> /builds/peterx/qemu/build/tests/qtest/virtio-net-failover --tap -k ――――――――――――――――――――――――――――――――――――― ✀ ――――――――――――――――――――――――――――――――――――― stderr: qemu-system-x86_64: ram_save_setup failed: Input/output error ** ERROR:../tests/qtest/virtio-net-failover.c:1203:test_migrate_abort_wait_unplug: assertion failed (status == "cancelling"): ("cancelled" == "cancelling") (test program exited with status code -6) ―――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――― I am not familiar enough with the failover code, and may not have time today to follow this up, copy Laurent. Cedric, if you have time, please have a look. I'll give it a shot on Monday to find a solution, otherwise we may need to postpone some of the patches to 9.1. Thanks, > + > qemu_savevm_wait_unplug(s, MIGRATION_STATUS_SETUP, > MIGRATION_STATUS_ACTIVE); > > @@ -3530,6 +3540,9 @@ static void *bg_migration_thread(void *opaque) > MigThrError thr_error; > QEMUFile *fb; > bool early_fail = true; > + bool setup_fail = true; > + Error *local_err = NULL; > + int ret; > > rcu_register_thread(); > object_ref(OBJECT(s)); > @@ -3563,9 +3576,16 @@ static void *bg_migration_thread(void *opaque) > > bql_lock(); > qemu_savevm_state_header(s->to_dst_file); > - qemu_savevm_state_setup(s->to_dst_file); > + ret = qemu_savevm_state_setup(s->to_dst_file, &local_err); > + if (ret) { > + migrate_set_error(s, local_err); > + error_free(local_err); > + goto fail; > + } > bql_unlock(); > > + setup_fail = false; > + > qemu_savevm_wait_unplug(s, MIGRATION_STATUS_SETUP, > MIGRATION_STATUS_ACTIVE); > > @@ -3632,7 +3652,8 @@ static void *bg_migration_thread(void *opaque) > > fail: > if (early_fail) { > - migrate_set_state(&s->state, MIGRATION_STATUS_ACTIVE, > + migrate_set_state(&s->state, > + setup_fail ? MIGRATION_STATUS_SETUP : > MIGRATION_STATUS_ACTIVE, > MIGRATION_STATUS_FAILED); > bql_unlock(); > } > diff --git a/migration/savevm.c b/migration/savevm.c > index > ee31ffb5e88cea723039c754c30ce2c8a0ef35f3..63fdbb5ad7d4dbfaef1d2094350bf302cc677602 > 100644 > --- a/migration/savevm.c > +++ b/migration/savevm.c > @@ -1310,11 +1310,11 @@ int qemu_savevm_state_prepare(Error **errp) > return 0; > } > > -void qemu_savevm_state_setup(QEMUFile *f) > +int qemu_savevm_state_setup(QEMUFile *f, Error **errp) > { > + ERRP_GUARD(); > MigrationState *ms = migrate_get_current(); > SaveStateEntry *se; > - Error *local_err = NULL; > int ret = 0; > > json_writer_int64(ms->vmdesc, "page_size", qemu_target_page_size()); > @@ -1323,10 +1323,9 @@ void qemu_savevm_state_setup(QEMUFile *f) > trace_savevm_state_setup(); > QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { > if (se->vmsd && se->vmsd->early_setup) { > - ret = vmstate_save(f, se, ms->vmdesc, &local_err); > + ret = vmstate_save(f, se, ms->vmdesc, errp); > if (ret) { > - migrate_set_error(ms, local_err); > - error_report_err(local_err); > + migrate_set_error(ms, *errp); > qemu_file_set_error(f, ret); > break; > } > @@ -1346,18 +1345,19 @@ void qemu_savevm_state_setup(QEMUFile *f) > ret = se->ops->save_setup(f, se->opaque); > save_section_footer(f, se); > if (ret < 0) { > + error_setg(errp, "failed to setup SaveStateEntry with id(name): " > + "%d(%s): %d", se->section_id, se->idstr, ret); > qemu_file_set_error(f, ret); > break; > } > } > > if (ret) { > - return; > + return ret; > } > > - if (precopy_notify(PRECOPY_NOTIFY_SETUP, &local_err)) { > - error_report_err(local_err); > - } > + /* TODO: Should we check that errp is set in case of failure ? */ > + return precopy_notify(PRECOPY_NOTIFY_SETUP, errp); > } > > int qemu_savevm_state_resume_prepare(MigrationState *s) > @@ -1728,7 +1728,10 @@ static int qemu_savevm_state(QEMUFile *f, Error **errp) > ms->to_dst_file = f; > > qemu_savevm_state_header(f); > - qemu_savevm_state_setup(f); > + ret = qemu_savevm_state_setup(f, errp); > + if (ret) { > + goto cleanup; > + } > > while (qemu_file_get_error(f) == 0) { > if (qemu_savevm_state_iterate(f, false) > 0) { > @@ -1741,10 +1744,11 @@ static int qemu_savevm_state(QEMUFile *f, Error > **errp) > qemu_savevm_state_complete_precopy(f, false, false); > ret = qemu_file_get_error(f); > } > - qemu_savevm_state_cleanup(); > if (ret != 0) { > error_setg_errno(errp, -ret, "Error while writing VM state"); > } > +cleanup: > + qemu_savevm_state_cleanup(); > > if (ret != 0) { > status = MIGRATION_STATUS_FAILED; > -- > 2.44.0 > -- Peter Xu