[PATCH 1/2] vhost-scsi: preserve event ordering

[physicalmtea@gmail.com]

From: Jia Jia <physicalmtea@gmail.com>

vhost_scsi_send_evt() uses llist_add(), so pending events are LIFO.
vhost_scsi_complete_events() walks the detached list directly.
This can deliver a later hotplug or hotunplug event before an earlier
one.

Reverse the detached list before processing it.
This keeps delivery in enqueue order.

Fixes: a6c9af87363c ("tcm_vhost: Add hotplug/hotunplug support")
Signed-off-by: Jia Jia <physicalmtea@gmail.com>
---
 drivers/vhost/scsi.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/vhost/scsi.c b/drivers/vhost/scsi.c
index 7a1f39a32..37f681aab 100644
--- a/drivers/vhost/scsi.c
+++ b/drivers/vhost/scsi.c
@@ -637,7 +637,7 @@ static void vhost_scsi_complete_events(struct vhost_scsi *vs, bool drop)
 	struct llist_node *llnode;
 
 	mutex_lock(&vq->mutex);
-	llnode = llist_del_all(&vs->vs_event_list);
+	llnode = llist_reverse_order(llist_del_all(&vs->vs_event_list));
 	llist_for_each_entry_safe(evt, t, llnode, list) {
 		if (!drop)
 			vhost_scsi_do_evt_work(vs, evt);
-- 
2.34.1