From f193bc0c5342496ce07355c0c30394560a7f4738 Mon Sep 17 00:00:00 2001 From: Ivan Ren Date: Tue, 25 Jun 2019 21:18:19 +0800 Subject: [PATCH] migration: fix migrate_cancel multifd migration leads destination hung forever When migrate_cancel a multifd migration, if run sequence like this: [source] [destination] multifd_send_sync_main[finish] multifd_recv_thread wait &p->sem_sync shutdown to_dst_file detect error from_src_file send RAM_SAVE_FLAG_EOS[fail] [no chance to run multifd_recv_sync_main] multifd_load_cleanup join multifd receive thread forever will lead destination qemu hung at following stack: pthread_join qemu_thread_join multifd_load_cleanup process_incoming_migration_co coroutine_trampoline Signed-off-by: Ivan Ren Reviewed-by: Dr. David Alan Gilbert Reviewed-by: Juan Quintela Message-Id: <1561468699-9819-4-git-send-email-ivanren@tencent.com> Signed-off-by: Juan Quintela --- migration/ram.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/migration/ram.c b/migration/ram.c index eb6716710e..889148dd84 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -1292,6 +1292,11 @@ int multifd_load_cleanup(Error **errp) if (p->running) { p->quit = true; + /* + * multifd_recv_thread may hung at MULTIFD_FLAG_SYNC handle code, + * however try to wakeup it without harm in cleanup phase. + */ + qemu_sem_post(&p->sem_sync); qemu_thread_join(&p->thread); } object_unref(OBJECT(p->c)); -- 2.11.4.GIT