Currently, if a qemu instance is started with "-incoming defer" and an incorect parameter is passed to "migrate_incoming", it will print the expected error and reply with "duplicate yank instance" for any upcoming "migrate_incoming" command.
This renders current qemu process unusable, and requires a new qemu process to be started before accepting a migration. This is caused by a yank_register_instance() that happens in qemu_start_incoming_migration() but is never reverted if any error happens. Solves this by unregistering the instance if anything goes wrong in the function, allowing a new "migrate_incoming" command to be accepted. Fixes: b5eea99ec2f ("migration: Add yank feature", 2021-01-13) Buglink: https://bugzilla.redhat.com/show_bug.cgi?id=1974366 Signed-off-by: Leonardo Bras <leob...@redhat.com> --- migration/migration.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/migration/migration.c b/migration/migration.c index 4228635d18..ddcf9e1868 100644 --- a/migration/migration.c +++ b/migration/migration.c @@ -474,9 +474,13 @@ static void qemu_start_incoming_migration(const char *uri, Error **errp) } else if (strstart(uri, "fd:", &p)) { fd_start_incoming_migration(p, errp); } else { - yank_unregister_instance(MIGRATION_YANK_INSTANCE); error_setg(errp, "unknown migration protocol: %s", uri); } + + if (*errp) { + yank_unregister_instance(MIGRATION_YANK_INSTANCE); + } + } static void process_incoming_migration_bh(void *opaque) -- 2.32.0