From: Bob Pearson rpearsonhpe@gmail.com
[ Upstream commit 15ae1375ea91ae2dee6f12d71a79d8c0a10a30bf ]
Currently the rdma_rxe driver attempts to protect atomic responder resources by taking a reference to the qp which is only freed when the resource is recycled for a new read or atomic operation. This means that in normal circumstances there is almost always an extra qp reference once an atomic operation has been executed which prevents cleaning up the qp and associated pd and cqs when the qp is destroyed.
This patch removes the call to rxe_add_ref() in send_atomic_ack() and the call to rxe_drop_ref() in free_rd_atomic_resource(). If the qp is destroyed while a peer is retrying an atomic op it will cause the operation to fail which is acceptable.
Link: https://lore.kernel.org/r/20210604230558.4812-1-rpearsonhpe@gmail.com Reported-by: Zhu Yanjun zyjzyj2000@gmail.com Fixes: 86af61764151 ("IB/rxe: remove unnecessary skb_clone") Signed-off-by: Bob Pearson rpearsonhpe@gmail.com Signed-off-by: Jason Gunthorpe jgg@nvidia.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/infiniband/sw/rxe/rxe_qp.c | 1 - drivers/infiniband/sw/rxe/rxe_resp.c | 2 -- 2 files changed, 3 deletions(-)
diff --git a/drivers/infiniband/sw/rxe/rxe_qp.c b/drivers/infiniband/sw/rxe/rxe_qp.c index 1e716fe7014c..a1b79015e6f2 100644 --- a/drivers/infiniband/sw/rxe/rxe_qp.c +++ b/drivers/infiniband/sw/rxe/rxe_qp.c @@ -125,7 +125,6 @@ static void free_rd_atomic_resources(struct rxe_qp *qp) void free_rd_atomic_resource(struct rxe_qp *qp, struct resp_res *res) { if (res->type == RXE_ATOMIC_MASK) { - rxe_drop_ref(qp); kfree_skb(res->atomic.skb); } else if (res->type == RXE_READ_MASK) { if (res->read.mr) diff --git a/drivers/infiniband/sw/rxe/rxe_resp.c b/drivers/infiniband/sw/rxe/rxe_resp.c index c7e3b6a4af38..83c03212099a 100644 --- a/drivers/infiniband/sw/rxe/rxe_resp.c +++ b/drivers/infiniband/sw/rxe/rxe_resp.c @@ -966,8 +966,6 @@ static int send_atomic_ack(struct rxe_qp *qp, struct rxe_pkt_info *pkt, goto out; }
- rxe_add_ref(qp); - res = &qp->resp.resources[qp->resp.res_head]; free_rd_atomic_resource(qp, res); rxe_advance_resp_resource(qp);