CA-419227 Missing PGPU in pool_migrate_complete on destination host (#6731)

There is a regression test fail between xapi v25.30.0 and v25.33.0. The
job is cross pool SXM with vGPU. The source host VM.migrate_send failed
with exception `Storage_error ([S(Does_not_exist);[S(mirror)` which is
raised by `MIRROR.stat`. The `MIRROR.stat` is triggered by destination
host in `pool_migrate_complete`. The error is
`Server_error(HANDLE_INVALID, [ PGPU; OpaqueRef:NULL ])`. I find
#6648 inserts
`force_state_reset_keep_current_operations` in `pool_migrate_complete`
which set VGPU resident_on to NULL. After reverting this commit, the job
pass.

Author: changlei-li

ocaml/xapi/xapi_vm_lifecycle.ml

@@ -862,6 +862,9 @@ let force_state_reset_keep_current_operations ~__context ~self ~value:state =
   (* First update the power_state. Some operations below indirectly rely on this. *)
   let old_state = Db.VM.get_power_state ~__context ~self in
   Db.VM.set_power_state ~__context ~self ~value:state ;
+  debug "%s: VM power state changed from %s to %s" __FUNCTION__
+    (Record_util.vm_power_state_to_string old_state)
+    (Record_util.vm_power_state_to_string state) ;
   if state = `Suspended then
     remove_pending_guidance ~__context ~self ~value:`restart_device_model ;
   if state = `Halted then (

ocaml/xapi/xapi_vm_migrate.ml

@@ -489,18 +489,18 @@ let pool_migrate_complete ~__context ~vm ~host:_ =
     ~value:`restart_device_model ;
   let dbg = Context.string_of_task __context in
   let queue_name = Xapi_xenops_queue.queue_of_vm ~__context ~self:vm in
-  (* Reset the state, which will update allowed operations, clear reservations
-     for halted VMs, disconnect devices *)
-  let power_state = Db.VM.get_power_state ~__context ~self:vm in
-  Xapi_vm_lifecycle.force_state_reset_keep_current_operations ~__context
-    ~self:vm ~value:power_state ;
   if Xapi_xenops.vm_exists_in_xenopsd queue_name dbg id then (
     remove_stale_pcis ~__context ~vm ;
     Xapi_xenops.set_resident_on ~__context ~self:vm ;
     Xapi_xenops.add_caches id ;
     Xapi_xenops.refresh_vm ~__context ~self:vm ;
     Monitor_dbcalls_cache.clear_cache_for_vm ~vm_uuid:id
   ) ;
+  (* Reset the state, which will update allowed operations, clear reservations
+     for halted VMs, disconnect devices *)
+  let power_state = Db.VM.get_power_state ~__context ~self:vm in
+  Xapi_vm_lifecycle.force_state_reset_keep_current_operations ~__context
+    ~self:vm ~value:power_state ;
   Xapi_vm_group_helpers.maybe_update_vm_anti_affinity_alert_for_vm ~__context
     ~vm
 
@@ -1100,6 +1100,7 @@ let vdi_copy_fun __context dbg vdi_map remote is_intra_pool remote_vdis so_far
         ) ;
       result
     with e ->
+      error "Catch error in post_mirror: %s" (Printexc.to_string e) ;
       let mirror_failed =
         match mirror_id with
         | Some mid ->