1 files changed, 26 insertions, 23 deletions

diff --git a/migration/migration.c b/migration/migration.c
index 7a14aa98d8..f242d657e8 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -184,16 +184,27 @@ static int migration_maybe_pause(MigrationState *s,
                                  int new_state);
 static void migrate_fd_cancel(MigrationState *s);
 
-static bool migrate_allow_multi_channels = true;
+static bool migration_needs_multiple_sockets(void)
+{
+    return migrate_use_multifd() || migrate_postcopy_preempt();
+}
 
-void migrate_protocol_allow_multi_channels(bool allow)
+static bool uri_supports_multi_channels(const char *uri)
 {
-    migrate_allow_multi_channels = allow;
+    return strstart(uri, "tcp:", NULL) || strstart(uri, "unix:", NULL) ||
+           strstart(uri, "vsock:", NULL);
 }
 
-bool migrate_multi_channels_is_allowed(void)
+static bool
+migration_channels_and_uri_compatible(const char *uri, Error **errp)
 {
-    return migrate_allow_multi_channels;
+    if (migration_needs_multiple_sockets() &&
+        !uri_supports_multi_channels(uri)) {
+        error_setg(errp, "Migration requires multi-channel URIs (e.g. tcp)");
+        return false;
+    }
+
+    return true;
 }
 
 static gint page_request_addr_cmp(gconstpointer ap, gconstpointer bp)
@@ -493,12 +504,15 @@ static void qemu_start_incoming_migration(const char *uri, Error **errp)
 {
     const char *p = NULL;
 
-    migrate_protocol_allow_multi_channels(false); /* reset it anyway */
+    /* URI is not suitable for migration? */
+    if (!migration_channels_and_uri_compatible(uri, errp)) {
+        return;
+    }
+
     qapi_event_send_migration(MIGRATION_STATUS_SETUP);
     if (strstart(uri, "tcp:", &p) ||
         strstart(uri, "unix:", NULL) ||
         strstart(uri, "vsock:", NULL)) {
-        migrate_protocol_allow_multi_channels(true);
         socket_start_incoming_migration(p ? p : uri, errp);
 #ifdef CONFIG_RDMA
     } else if (strstart(uri, "rdma:", &p)) {
@@ -723,11 +737,6 @@ void migration_fd_process_incoming(QEMUFile *f, Error **errp)
     migration_incoming_process();
 }
 
-static bool migration_needs_multiple_sockets(void)
-{
-    return migrate_use_multifd() || migrate_postcopy_preempt();
-}
-
 void migration_ioc_process_incoming(QIOChannel *ioc, Error **errp)
 {
     MigrationIncomingState *mis = migration_incoming_get_current();
@@ -1378,15 +1387,6 @@ static bool migrate_caps_check(bool *cap_list,
     }
 #endif
 
-
-    /* incoming side only */
-    if (runstate_check(RUN_STATE_INMIGRATE) &&
-        !migrate_multi_channels_is_allowed() &&
-        cap_list[MIGRATION_CAPABILITY_MULTIFD]) {
-        error_setg(errp, "multifd is not supported by current protocol");
-        return false;
-    }
-
     if (cap_list[MIGRATION_CAPABILITY_POSTCOPY_PREEMPT]) {
         if (!cap_list[MIGRATION_CAPABILITY_POSTCOPY_RAM]) {
             error_setg(errp, "Postcopy preempt requires postcopy-ram");
@@ -2471,6 +2471,11 @@ void qmp_migrate(const char *uri, bool has_blk, bool blk,
     MigrationState *s = migrate_get_current();
     const char *p = NULL;
 
+    /* URI is not suitable for migration? */
+    if (!migration_channels_and_uri_compatible(uri, errp)) {
+        return;
+    }
+
     if (!migrate_prepare(s, has_blk && blk, has_inc && inc,
                          has_resume && resume, errp)) {
         /* Error detected, put into errp */
@@ -2483,11 +2488,9 @@ void qmp_migrate(const char *uri, bool has_blk, bool blk,
         }
     }
 
-    migrate_protocol_allow_multi_channels(false);
     if (strstart(uri, "tcp:", &p) ||
         strstart(uri, "unix:", NULL) ||
         strstart(uri, "vsock:", NULL)) {
-        migrate_protocol_allow_multi_channels(true);
         socket_start_outgoing_migration(s, p ? p : uri, &local_err);
 #ifdef CONFIG_RDMA
     } else if (strstart(uri, "rdma:", &p)) {