2022-01-03 9:02 GMT+09:00, Hyunchul Lee <hyc.lee@xxxxxxxxx>:
> if CONFIG_LOCKDEP is enabled, the following
> kernel warning message is generated because
> rdma_accept() is called not under CM(Connection
> Manager) handler.
>
> [ 63.211405 ] WARNING: CPU: 1 PID: 345 at
> drivers/infiniband/core/cma.c:4405 rdma_accept+0x17a/0x350
> [ 63.212080 ] RIP: 0010:rdma_accept+0x17a/0x350
> ...
> [ 63.214036 ] Call Trace:
> [ 63.214098 ] <TASK>
> [ 63.214185 ] smb_direct_accept_client+0xb4/0x170 [ksmbd]
> [ 63.214412 ] smb_direct_prepare+0x322/0x8c0 [ksmbd]
> [ 63.214555 ] ? rcu_read_lock_sched_held+0x3a/0x70
> [ 63.214700 ] ksmbd_conn_handler_loop+0x63/0x270 [ksmbd]
> [ 63.214826 ] ? ksmbd_conn_alive+0x80/0x80 [ksmbd]
> [ 63.214952 ] kthread+0x171/0x1a0
> [ 63.215039 ] ? set_kthread_struct+0x40/0x40
> [ 63.215128 ] ret_from_fork+0x22/0x30
I could not understand why lockdep trigger this warning.
Could you elaborate more ?
>
> To avoid this, move creating a queue pair and accepting
> a client from transport_ops->prepare() to
> smb_direct_handle_connect_request().
>
> Signed-off-by: Hyunchul Lee <hyc.lee@xxxxxxxxx>
> ---
> fs/ksmbd/transport_rdma.c | 97 +++++++++++++++++++++++----------------
> 1 file changed, 57 insertions(+), 40 deletions(-)
>
> diff --git a/fs/ksmbd/transport_rdma.c b/fs/ksmbd/transport_rdma.c
> index f89b64e27836..b37e4b9580ae 100644
> --- a/fs/ksmbd/transport_rdma.c
> +++ b/fs/ksmbd/transport_rdma.c
> @@ -568,6 +568,7 @@ static void recv_done(struct ib_cq *cq, struct ib_wc
> *wc)
> }
> t->negotiation_requested = true;
> t->full_packet_received = true;
> + enqueue_reassembly(t, recvmsg, 0);
Is this a fix related to this patch?
> wake_up_interruptible(&t->wait_status);
> break;
> case SMB_DIRECT_MSG_DATA_TRANSFER: {
> @@ -1594,19 +1595,13 @@ static int smb_direct_accept_client(struct
> smb_direct_transport *t)
> pr_err("error at rdma_accept: %d\n", ret);
> return ret;
> }
> -
> - wait_event_interruptible(t->wait_status,
> - t->status != SMB_DIRECT_CS_NEW);
> - if (t->status != SMB_DIRECT_CS_CONNECTED)
> - return -ENOTCONN;
> return 0;
> }
>
> -static int smb_direct_negotiate(struct smb_direct_transport *t)
> +static int smb_direct_prepare_negotiation(struct smb_direct_transport *t)
> {
> int ret;
> struct smb_direct_recvmsg *recvmsg;
> - struct smb_direct_negotiate_req *req;
>
> recvmsg = get_free_recvmsg(t);
> if (!recvmsg)
> @@ -1616,44 +1611,20 @@ static int smb_direct_negotiate(struct
> smb_direct_transport *t)
> ret = smb_direct_post_recv(t, recvmsg);
> if (ret) {
> pr_err("Can't post recv: %d\n", ret);
> - goto out;
> + goto out_err;
> }
>
> t->negotiation_requested = false;
> ret = smb_direct_accept_client(t);
> if (ret) {
> pr_err("Can't accept client\n");
> - goto out;
> + goto out_err;
> }
>
> smb_direct_post_recv_credits(&t->post_recv_credits_work.work);
> -
> - ksmbd_debug(RDMA, "Waiting for SMB_DIRECT negotiate request\n");
> - ret = wait_event_interruptible_timeout(t->wait_status,
> - t->negotiation_requested ||
> - t->status == SMB_DIRECT_CS_DISCONNECTED,
> - SMB_DIRECT_NEGOTIATE_TIMEOUT * HZ);
> - if (ret <= 0 || t->status == SMB_DIRECT_CS_DISCONNECTED) {
> - ret = ret < 0 ? ret : -ETIMEDOUT;
> - goto out;
> - }
> -
> - ret = smb_direct_check_recvmsg(recvmsg);
> - if (ret == -ECONNABORTED)
> - goto out;
> -
> - req = (struct smb_direct_negotiate_req *)recvmsg->packet;
> - t->max_recv_size = min_t(int, t->max_recv_size,
> - le32_to_cpu(req->preferred_send_size));
> - t->max_send_size = min_t(int, t->max_send_size,
> - le32_to_cpu(req->max_receive_size));
> - t->max_fragmented_send_size =
> - le32_to_cpu(req->max_fragmented_size);
> -
> - ret = smb_direct_send_negotiate_response(t, ret);
> -out:
> - if (recvmsg)
> - put_recvmsg(t, recvmsg);
> + return 0;
> +out_err:
> + put_recvmsg(t, recvmsg);
> return ret;
> }
>
> @@ -1890,6 +1861,47 @@ static int smb_direct_create_qpair(struct
> smb_direct_transport *t,
> static int smb_direct_prepare(struct ksmbd_transport *t)
> {
> struct smb_direct_transport *st = smb_trans_direct_transfort(t);
> + struct smb_direct_recvmsg *recvmsg;
> + struct smb_direct_negotiate_req *req;
> + int ret;
> +
> + ksmbd_debug(RDMA, "Waiting for SMB_DIRECT negotiate request\n");
> + ret = wait_event_interruptible_timeout(st->wait_status,
> + st->negotiation_requested ||
> + st->status == SMB_DIRECT_CS_DISCONNECTED,
> + SMB_DIRECT_NEGOTIATE_TIMEOUT * HZ);
> + if (ret <= 0 || st->status == SMB_DIRECT_CS_DISCONNECTED)
> + return ret < 0 ? ret : -ETIMEDOUT;
> +
> + recvmsg = get_first_reassembly(st);
> + if (!recvmsg)
> + return -ECONNABORTED;
> +
> + ret = smb_direct_check_recvmsg(recvmsg);
> + if (ret == -ECONNABORTED)
> + goto out;
> +
> + req = (struct smb_direct_negotiate_req *)recvmsg->packet;
> + st->max_recv_size = min_t(int, st->max_recv_size,
> + le32_to_cpu(req->preferred_send_size));
> + st->max_send_size = min_t(int, st->max_send_size,
> + le32_to_cpu(req->max_receive_size));
> + st->max_fragmented_send_size =
> + le32_to_cpu(req->max_fragmented_size);
> +
> + ret = smb_direct_send_negotiate_response(st, ret);
> +out:
> + spin_lock_irq(&st->reassembly_queue_lock);
> + st->reassembly_queue_length--;
> + list_del(&recvmsg->list);
> + spin_unlock_irq(&st->reassembly_queue_lock);
> + put_recvmsg(st, recvmsg);
> +
> + return ret;
> +}
> +
> +static int smb_direct_connect(struct smb_direct_transport *st)
> +{
> int ret;
> struct ib_qp_cap qp_cap;
>
> @@ -1911,13 +1923,11 @@ static int smb_direct_prepare(struct ksmbd_transport
> *t)
> return ret;
> }
>
> - ret = smb_direct_negotiate(st);
> + ret = smb_direct_prepare_negotiation(st);
> if (ret) {
> pr_err("Can't negotiate: %d\n", ret);
> return ret;
> }
> -
> - st->status = SMB_DIRECT_CS_CONNECTED;
> return 0;
> }
>
> @@ -1933,6 +1943,7 @@ static bool rdma_frwr_is_supported(struct
> ib_device_attr *attrs)
> static int smb_direct_handle_connect_request(struct rdma_cm_id *new_cm_id)
> {
> struct smb_direct_transport *t;
> + int ret;
>
> if (!rdma_frwr_is_supported(&new_cm_id->device->attrs)) {
> ksmbd_debug(RDMA,
> @@ -1945,11 +1956,17 @@ static int smb_direct_handle_connect_request(struct
> rdma_cm_id *new_cm_id)
> if (!t)
> return -ENOMEM;
>
> + ret = smb_direct_connect(t);
> + if (ret) {
> + free_transport(t);
> + return ret;
I think that it is better to use goto statement to out after freeing
transport structure.
> + }
> +
> KSMBD_TRANS(t)->handler = kthread_run(ksmbd_conn_handler_loop,
> KSMBD_TRANS(t)->conn, "ksmbd:r%u",
> smb_direct_port);
> if (IS_ERR(KSMBD_TRANS(t)->handler)) {
> - int ret = PTR_ERR(KSMBD_TRANS(t)->handler);
> + ret = PTR_ERR(KSMBD_TRANS(t)->handler);
>
> pr_err("Can't start thread\n");
> free_transport(t);
> --
> 2.25.1
>
>
