Some of the migration parameters are strings, which default to NULL, eg tls_hostname and tls_creds.
The mgmt app will set the tls_creds parameter on both source and target QEMU instances, in order to trigger use of TLS for migration. After performing a TLS encrypted migration though, migration might be used for other reasons - for example, to save the QEMU state to a file. We need TLS turned off when doing this, but the migrate-set-parameters QAPI command does not provide any facility to clear/reset parameters to their default state. If you simply ommit the tls_creds parameter in migrate-set-parameters, then 'has_tls_creds' will be false and so no action will be taken. The only option that works with migrate-set-parameters is to treat "" on the wire as equivalent to requesting NULL. Failing that we would have to create a new 'migrate-reset-parameters' method to explicitly put a parameter back to its default value. Signed-off-by: Daniel P. Berrange <berra...@redhat.com> --- CC'ing Eric & Markus since this is related to QAPI schema for migrate monitor commands migration/migration.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/migration/migration.c b/migration/migration.c index c6ae69d..a5d41a9 100644 --- a/migration/migration.c +++ b/migration/migration.c @@ -872,11 +872,19 @@ void qmp_migrate_set_parameters(MigrationParameters *params, Error **errp) } if (params->has_tls_creds) { g_free(s->parameters.tls_creds); - s->parameters.tls_creds = g_strdup(params->tls_creds); + if (*params->tls_creds == '\0') { + s->parameters.tls_creds = NULL; + } else { + s->parameters.tls_creds = g_strdup(params->tls_creds); + } } if (params->has_tls_hostname) { g_free(s->parameters.tls_hostname); - s->parameters.tls_hostname = g_strdup(params->tls_hostname); + if (*params->tls_hostnane == '\0') { + s->parameters.tls_hostnane = NULL; + } else { + s->parameters.tls_hostname = g_strdup(params->tls_hostname); + } } if (params->has_max_bandwidth) { s->parameters.max_bandwidth = params->max_bandwidth; -- 2.9.3