Re: [Qemu-devel] [PATCH] Migration: Generate the completed event only when we complete

[Amit Shah]

On (Tue) 13 Oct 2015 [12:21:27], Dr. David Alan Gilbert (git) wrote:
> From: "Dr. David Alan Gilbert" <address@hidden>
> 
> The current migration-completed event is generated a bit too early,
> which means that an eager libvirt that's ready to go as soon
> as it sees the event ends up racing with the actual end of migration.
> 
> This corresponds to RH bug:
> https://bugzilla.redhat.com/show_bug.cgi?id=1271145
> 
> Signed-off-by: Dr. David Alan Gilbert <address@hidden>

Reviewed-by: Amit Shah <address@hidden>

>  migration/migration.c | 8 +++++++-
>  1 file changed, 7 insertions(+), 1 deletion(-)
> 
> diff --git a/migration/migration.c b/migration/migration.c
> index b7de9b7..3d40f24 100644
> --- a/migration/migration.c
> +++ b/migration/migration.c
> @@ -294,12 +294,12 @@ static void process_incoming_migration_co(void *opaque)
>          migrate_decompress_threads_join();
>          exit(EXIT_FAILURE);
>      }
> -    migrate_generate_event(MIGRATION_STATUS_COMPLETED);
>      qemu_announce_self();

Related in this context (but independent of this patch): this
announce_self should happen after we're through with all the error
cases: we don't want to announce our new IP and end up having run on
src due to a failed migration.

>      /* Make sure all file formats flush their mutable metadata */
>      bdrv_invalidate_cache_all(&local_err);
>      if (local_err) {
> +        migrate_generate_event(MIGRATION_STATUS_FAILED);
>          error_report_err(local_err);
>          migrate_decompress_threads_join();
>          exit(EXIT_FAILURE);

                Amit