From dce8921b2baaf95974af8176406881872067adfa Mon Sep 17 00:00:00 2001 From: Fam Zheng Date: Thu, 8 Sep 2016 17:28:51 +0800 Subject: iothread: Stop threads before main() quits Right after main_loop ends, we release various things but keep iothread alive. The latter is not prepared to the sudden change of resources. Specifically, after bdrv_close_all(), virtio-scsi dataplane get a surprise at the empty BlockBackend: (gdb) bt at /usr/src/debug/qemu-2.6.0/hw/scsi/virtio-scsi.c:543 at /usr/src/debug/qemu-2.6.0/hw/scsi/virtio-scsi.c:577 It is because the d->conf.blk->root is set to NULL, then blk_get_aio_context() returns qemu_aio_context, whereas s->ctx is still pointing to the iothread: hw/scsi/virtio-scsi.c:543: if (s->dataplane_started) { assert(blk_get_aio_context(d->conf.blk) == s->ctx); } To fix this, let's stop iothreads before doing bdrv_close_all(). Cc: qemu-stable@nongnu.org Signed-off-by: Fam Zheng Reviewed-by: Paolo Bonzini Message-id: 1473326931-9699-1-git-send-email-famz@redhat.com Signed-off-by: Stefan Hajnoczi --- iothread.c | 24 ++++++++++++++++++++---- 1 file changed, 20 insertions(+), 4 deletions(-) (limited to 'iothread.c') diff --git a/iothread.c b/iothread.c index f183d380e6..fb08a60b4b 100644 --- a/iothread.c +++ b/iothread.c @@ -54,16 +54,25 @@ static void *iothread_run(void *opaque) return NULL; } -static void iothread_instance_finalize(Object *obj) +static int iothread_stop(Object *object, void *opaque) { - IOThread *iothread = IOTHREAD(obj); + IOThread *iothread; - if (!iothread->ctx) { - return; + iothread = (IOThread *)object_dynamic_cast(object, TYPE_IOTHREAD); + if (!iothread || !iothread->ctx) { + return 0; } iothread->stopping = true; aio_notify(iothread->ctx); qemu_thread_join(&iothread->thread); + return 0; +} + +static void iothread_instance_finalize(Object *obj) +{ + IOThread *iothread = IOTHREAD(obj); + + iothread_stop(obj, NULL); qemu_cond_destroy(&iothread->init_done_cond); qemu_mutex_destroy(&iothread->init_done_lock); aio_context_unref(iothread->ctx); @@ -174,3 +183,10 @@ IOThreadInfoList *qmp_query_iothreads(Error **errp) object_child_foreach(container, query_one_iothread, &prev); return head; } + +void iothread_stop_all(void) +{ + Object *container = object_get_objects_root(); + + object_child_foreach(container, iothread_stop, NULL); +} -- cgit v1.2.1