From: "Dr. David Alan Gilbert" <dgilb...@redhat.com> The 'status' field for the migration is updated normally using an atomic operation from the migration thread. Most readers of it aren't that careful, and in most cases it doesn't matter.
In query_migrate->fill_source_migration_info the 'state' is read twice; the first time to decide which state fields to fill in, and then secondly to copy the state to the status field; that can end up with a status that's inconsistent; e.g. setting up the fields for 'setup' and then having an 'active' status. In that case libvirt gets upset by the lack of ram info. The symptom is: libvirt.libvirtError: internal error: migration was active, but no RAM info was set Read the state exactly once in fill_source_migration_info. This is a possible fix for: https://bugzilla.redhat.com/show_bug.cgi?id=2074205 Signed-off-by: Dr. David Alan Gilbert <dgilb...@redhat.com> Message-Id: <20220413113329.103696-1-dgilb...@redhat.com> Reviewed-by: Juan Quintela <quint...@redhat.com> Reviewed-by: Peter Xu <pet...@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilb...@redhat.com> --- migration/migration.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/migration/migration.c b/migration/migration.c index 03ae53074b..4bc68100b4 100644 --- a/migration/migration.c +++ b/migration/migration.c @@ -1084,6 +1084,7 @@ static void populate_disk_info(MigrationInfo *info) static void fill_source_migration_info(MigrationInfo *info) { MigrationState *s = migrate_get_current(); + int state = qatomic_read(&s->state); GSList *cur_blocker = migration_blockers; info->blocked_reasons = NULL; @@ -1103,7 +1104,7 @@ static void fill_source_migration_info(MigrationInfo *info) } info->has_blocked_reasons = info->blocked_reasons != NULL; - switch (s->state) { + switch (state) { case MIGRATION_STATUS_NONE: /* no migration has happened ever */ /* do not overwrite destination migration status */ @@ -1148,7 +1149,7 @@ static void fill_source_migration_info(MigrationInfo *info) info->has_status = true; break; } - info->status = s->state; + info->status = state; } typedef enum WriteTrackingSupport { -- 2.35.1
