[PULL 2/6] migration: failover: emit a warning when the card is not fully unplugged

["Dr. David Alan Gilbert (git)" <dgilbert@redhat.com>]

From: Laurent Vivier <lvivier@redhat.com>

When the migration fails or is canceled we wait the end of the unplug
operation to be able to plug it back. But if the unplug operation
is never finished we stop to wait and QEMU emits a warning to inform
the user.

Based-on: 20210629155007.629086-1-lvivier@redhat.com
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Message-Id: <20210701131458.112036-1-lvivier@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
---
 migration/migration.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/migration/migration.c b/migration/migration.c
index 5ff7ba9d5c..d717cd089a 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -3701,6 +3701,10 @@ static void qemu_savevm_wait_unplug(MigrationState *s, int old_state,
             while (timeout-- && qemu_savevm_state_guest_unplug_pending()) {
                 qemu_sem_timedwait(&s->wait_unplug_sem, 250);
             }
+            if (qemu_savevm_state_guest_unplug_pending()) {
+                warn_report("migration: partially unplugged device on "
+                            "failure");
+            }
         }
 
         migrate_set_state(&s->state, MIGRATION_STATUS_WAIT_UNPLUG, new_state);
-- 
2.31.1