Re: [PATCH for-next v3 2/2] RDMA/rxe: Fix mr leak in RESPST_ERR_RNR

Bob Pearson
2022-10-24T16:12:59Z

On 10/24/22 00:20, Li Zhijian wrote:
> rxe_recheck_mr() will increase mr's ref_cnt, so we should call rxe_put(mr)
> to drop mr's ref_cnt in RESPST_ERR_RNR to avoid below warning:
> [ 633.447883] WARNING: CPU: 0 PID: 4156 at drivers/infiniband/sw/rxe/rxe_pool.c:259 __rxe_cleanup+0x1df/0x240 [rdma_rxe]
> ...
> [ 633.509482] Call Trace:
> [ 633.510246] <TASK>
> [ 633.510962] rxe_dereg_mr+0x4c/0x60 [rdma_rxe]
> [ 633.512123] ib_dereg_mr_user+0xa8/0x200 [ib_core]
> [ 633.513444] ib_mr_pool_destroy+0x77/0xb0 [ib_core]
> [ 633.514763] nvme_rdma_destroy_queue_ib+0x89/0x240 [nvme_rdma]
> [ 633.516230] nvme_rdma_free_queue+0x40/0x50 [nvme_rdma]
> [ 633.517577] nvme_rdma_teardown_io_queues.part.0+0xc3/0x120 [nvme_rdma]
> [ 633.519204] nvme_rdma_error_recovery_work+0x4d/0xf0 [nvme_rdma]
> [ 633.520695] process_one_work+0x582/0xa40
> [ 633.522987] ? pwq_dec_nr_in_flight+0x100/0x100
> [ 633.524227] ? rwlock_bug.part.0+0x60/0x60
> [ 633.525372] worker_thread+0x2a9/0x700
> [ 633.526437] ? process_one_work+0xa40/0xa40
> [ 633.527589] kthread+0x168/0x1a0
> [ 633.528518] ? kthread_complete_and_exit+0x20/0x20
> [ 633.529792] ret_from_fork+0x22/0x30
>
> CC: Bob Pearson <rpearsonhpe@gmail.com>
> Fixes: 8a1a0be894da ("RDMA/rxe: Replace mr by rkey in responder resources")
> Signed-off-by: Li Zhijian <lizhijian@fujitsu.com>
> V2: remove mr testing
> ---
> drivers/infiniband/sw/rxe/rxe_resp.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/infiniband/sw/rxe/rxe_resp.c b/drivers/infiniband/sw/rxe/rxe_resp.c
> index b02639cf8cba..41250154a478 100644
> --- a/drivers/infiniband/sw/rxe/rxe_resp.c
> +++ b/drivers/infiniband/sw/rxe/rxe_resp.c
> @@ -806,8 +806,10 @@ static enum resp_states read_reply(struct rxe_qp *qp,
>
> skb = prepare_ack_packet(qp, &ack_pkt, opcode, payload,
> res->cur_psn, AETH_ACK_UNLIMITED);
> - if (!skb)
> + if (!skb) {
> + rxe_put(mr);
> return RESPST_ERR_RNR;
> + }
>
> rxe_mr_copy(mr, res->read.va, payload_addr(&ack_pkt),
> payload, RXE_FROM_MR_OBJ);

This is correct. Good catch. Needs cleanup per Leon otherwise it's good.

Bob