diff options
Diffstat (limited to 'drivers/net/enic/vnic_wq.h')
| -rw-r--r-- | drivers/net/enic/vnic_wq.h | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/drivers/net/enic/vnic_wq.h b/drivers/net/enic/vnic_wq.h index 7081828..c826137 100644 --- a/drivers/net/enic/vnic_wq.h +++ b/drivers/net/enic/vnic_wq.h @@ -108,8 +108,15 @@ static inline void vnic_wq_post(struct vnic_wq *wq, buf->len = len; buf = buf->next; - if (eop) + if (eop) { + /* Adding write memory barrier prevents compiler and/or CPU + * reordering, thus avoiding descriptor posting before + * descriptor is initialized. Otherwise, hardware can read + * stale descriptor fields. + */ + wmb(); iowrite32(buf->index, &wq->ctrl->posted_index); + } wq->to_use = buf; wq->ring.desc_avail--; |
