diff options
| author | Bart Van Assche <bart.vanassche@wdc.com> | 2018-01-12 15:11:58 -0800 |
|---|---|---|
| committer | Doug Ledford <dledford@redhat.com> | 2018-01-18 14:49:19 -0500 |
| commit | 65567e41219888feec72fee1de98ccf1efbbc16d (patch) | |
| tree | 5d1c39d42c4c0d89f461fc7159e8a49dcab8f7d6 /drivers/infiniband/sw | |
| parent | 37cb11acf1f72a007a85894a6dd2ec93932bde46 (diff) | |
RDMA/rxe: Fix a race condition in rxe_requester()
The rxe driver works as follows:
* The send queue, receive queue and completion queues are implemented as
circular buffers.
* ib_post_send() and ib_post_recv() calls are serialized through a spinlock.
* Removing elements from various queues happens from tasklet
context. Tasklets are guaranteed to run on at most one CPU. This serializes
access to these queues. See also rxe_completer(), rxe_requester() and
rxe_responder().
* rxe_completer() processes the skbs queued onto qp->resp_pkts.
* rxe_requester() handles the send queue (qp->sq.queue).
* rxe_responder() processes the skbs queued onto qp->req_pkts.
Since rxe_drain_req_pkts() processes qp->req_pkts, calling
rxe_drain_req_pkts() from rxe_requester() is racy. Hence this patch.
Reported-by: Moni Shoua <monis@mellanox.com>
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Cc: stable@vger.kernel.org
Signed-off-by: Doug Ledford <dledford@redhat.com>
Diffstat (limited to 'drivers/infiniband/sw')
| -rw-r--r-- | drivers/infiniband/sw/rxe/rxe_loc.h | 1 | ||||
| -rw-r--r-- | drivers/infiniband/sw/rxe/rxe_req.c | 9 | ||||
| -rw-r--r-- | drivers/infiniband/sw/rxe/rxe_resp.c | 2 |
3 files changed, 2 insertions, 10 deletions
diff --git a/drivers/infiniband/sw/rxe/rxe_loc.h b/drivers/infiniband/sw/rxe/rxe_loc.h index d7472a442a2c..96c3a6c5c4b5 100644 --- a/drivers/infiniband/sw/rxe/rxe_loc.h +++ b/drivers/infiniband/sw/rxe/rxe_loc.h @@ -237,7 +237,6 @@ int rxe_srq_from_attr(struct rxe_dev *rxe, struct rxe_srq *srq, void rxe_release(struct kref *kref); -void rxe_drain_req_pkts(struct rxe_qp *qp, bool notify); int rxe_completer(void *arg); int rxe_requester(void *arg); int rxe_responder(void *arg); diff --git a/drivers/infiniband/sw/rxe/rxe_req.c b/drivers/infiniband/sw/rxe/rxe_req.c index 26a7f923045b..7bdaf71b8221 100644 --- a/drivers/infiniband/sw/rxe/rxe_req.c +++ b/drivers/infiniband/sw/rxe/rxe_req.c @@ -594,15 +594,8 @@ int rxe_requester(void *arg) rxe_add_ref(qp); next_wqe: - if (unlikely(!qp->valid)) { - rxe_drain_req_pkts(qp, true); + if (unlikely(!qp->valid || qp->req.state == QP_STATE_ERROR)) goto exit; - } - - if (unlikely(qp->req.state == QP_STATE_ERROR)) { - rxe_drain_req_pkts(qp, true); - goto exit; - } if (unlikely(qp->req.state == QP_STATE_RESET)) { qp->req.wqe_index = consumer_index(qp->sq.queue); diff --git a/drivers/infiniband/sw/rxe/rxe_resp.c b/drivers/infiniband/sw/rxe/rxe_resp.c index f07324f2cde2..d37bb9b97569 100644 --- a/drivers/infiniband/sw/rxe/rxe_resp.c +++ b/drivers/infiniband/sw/rxe/rxe_resp.c @@ -1209,7 +1209,7 @@ static enum resp_states do_class_d1e_error(struct rxe_qp *qp) } } -void rxe_drain_req_pkts(struct rxe_qp *qp, bool notify) +static void rxe_drain_req_pkts(struct rxe_qp *qp, bool notify) { struct sk_buff *skb; |