From: Li Zhijian <lizhijian@fujitsu.com>

Commit 4881411136 ("migration: Always set DEVICE state") set a new DEVICE
state before completed during migration, which broke the original transition
to COLO. The migration flow for precopy has changed to:
active -> pre-switchover -> device -> completed.

This patch updates the transition state to ensure that the Pre-COLO
state corresponds to DEVICE state correctly.

Cc: qemu-stable <qemu-stable@nongnu.org>
Fixes: 4881411136 ("migration: Always set DEVICE state")
Signed-off-by: Li Zhijian <lizhijian@fujitsu.com>
Reviewed-by: Zhang Chen <zhangckid@gmail.com>
Tested-by: Zhang Chen <zhangckid@gmail.com>
Link: https://lore.kernel.org/r/20251104013606.1937764-1-lizhijian@fujitsu.com
Signed-off-by: Peter Xu <peterx@redhat.com>
(cherry picked from commit 0b5bf4ea76205a93386c5e02fbb519871a62e677)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>

diff --git a/migration/migration.c b/migration/migration.c
index 32b8ce5613..e806481456 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -3047,9 +3047,9 @@ static void migration_completion(MigrationState *s)
         goto fail;
     }
 
-    if (migrate_colo() && s->state == MIGRATION_STATUS_ACTIVE) {
+    if (migrate_colo() && s->state == MIGRATION_STATUS_DEVICE) {
         /* COLO does not support postcopy */
-        migrate_set_state(&s->state, MIGRATION_STATUS_ACTIVE,
+        migrate_set_state(&s->state, MIGRATION_STATUS_DEVICE,
                           MIGRATION_STATUS_COLO);
     } else {
         migration_completion_end(s);
-- 
2.47.3