Re: [PATCH 2/2] migration: Allow reset of postcopy_recover_triggered when failed

[Dr. David Alan Gilbert]

* Peter Xu (peterx@redhat.com) wrote:
> It's possible qemu_start_incoming_migration() failed at any point, when it
> happens we should reset postcopy_recover_triggered to false so that the user
> can still retry with a saner incoming port.
> 
> Signed-off-by: Peter Xu <peterx@redhat.com>

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>

> ---
>  migration/migration.c | 13 +++++++++++++
>  1 file changed, 13 insertions(+)
> 
> diff --git a/migration/migration.c b/migration/migration.c
> index 1bb03d1eca..fcca289ef7 100644
> --- a/migration/migration.c
> +++ b/migration/migration.c
> @@ -2097,6 +2097,13 @@ void qmp_migrate_recover(const char *uri, Error **errp)
>  {
>      MigrationIncomingState *mis = migration_incoming_get_current();
>  
> +    /*
> +     * Don't even bother to use ERRP_GUARD() as it _must_ always be set by
> +     * callers (no one should ignore a recover failure); if there is, it's a
> +     * programming error.
> +     */
> +    assert(errp);
> +
>      if (mis->state != MIGRATION_STATUS_POSTCOPY_PAUSED) {
>          error_setg(errp, "Migrate recover can only be run "
>                     "when postcopy is paused.");
> @@ -2115,6 +2122,12 @@ void qmp_migrate_recover(const char *uri, Error **errp)
>       * to continue using that newly established channel.
>       */
>      qemu_start_incoming_migration(uri, errp);
> +
> +    /* Safe to dereference with the assert above */
> +    if (*errp) {
> +        /* Reset the flag so user could still retry */
> +        qatomic_set(&mis->postcopy_recover_triggered, false);
> +    }
>  }
>  
>  void qmp_migrate_pause(Error **errp)
> -- 
> 2.31.1
> 
-- 
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK