On Tue, Apr 18, 2023 at 5:07 PM Daisuke Matsuda
<matsuda-daisuke@xxxxxxxxxxx> wrote:
>
> After applying commit f605f26ea196, the following deadlock is observed:
> Call Trace:
> <IRQ>
> _raw_spin_lock_bh+0x29/0x30
> check_type_state.constprop.0+0x4e/0xc0 [rdma_rxe]
> rxe_rcv+0x173/0x3d0 [rdma_rxe]
> rxe_udp_encap_recv+0x69/0xd0 [rdma_rxe]
> ? __pfx_rxe_udp_encap_recv+0x10/0x10 [rdma_rxe]
> udp_queue_rcv_one_skb+0x258/0x520
> udp_unicast_rcv_skb+0x75/0x90
> __udp4_lib_rcv+0x364/0x5c0
> ip_protocol_deliver_rcu+0xa7/0x160
> ip_local_deliver_finish+0x73/0xa0
> ip_sublist_rcv_finish+0x80/0x90
> ip_sublist_rcv+0x191/0x220
> ip_list_rcv+0x132/0x160
> __netif_receive_skb_list_core+0x297/0x2c0
> netif_receive_skb_list_internal+0x1c5/0x300
> napi_complete_done+0x6f/0x1b0
> virtnet_poll+0x1f4/0x2d0 [virtio_net]
> __napi_poll+0x2c/0x1b0
> net_rx_action+0x293/0x350
> ? __napi_schedule+0x79/0x90
> __do_softirq+0xcb/0x2ab
> __irq_exit_rcu+0xb9/0xf0
> common_interrupt+0x80/0xa0
> </IRQ>
> <TASK>
> asm_common_interrupt+0x22/0x40
> RIP: 0010:_raw_spin_lock+0x17/0x30
> rxe_requester+0xe4/0x8f0 [rdma_rxe]
> ? xas_load+0x9/0xa0
> ? xa_load+0x70/0xb0
> do_task+0x64/0x1f0 [rdma_rxe]
> rxe_post_send+0x54/0x110 [rdma_rxe]
> ib_uverbs_post_send+0x5f8/0x680 [ib_uverbs]
> ? netif_receive_skb_list_internal+0x1e3/0x300
> ib_uverbs_write+0x3c8/0x500 [ib_uverbs]
> vfs_write+0xc5/0x3b0
> ksys_write+0xab/0xe0
> ? syscall_trace_enter.constprop.0+0x126/0x1a0
> do_syscall_64+0x3b/0x90
> entry_SYSCALL_64_after_hwframe+0x72/0xdc
> </TASK>
>
> The deadlock is easily reproducible with perftest. Fix it by disabling
> softirq when acquiring the lock in process context.
I am fine. Thanks.
Acked-by: Zhu Yanjun <zyjzyj2000@xxxxxxxxx>
Zhu Yanjun
>
> Fixes: f605f26ea196 ("RDMA/rxe: Protect QP state with qp->state_lock")
> Signed-off-by: Daisuke Matsuda <matsuda-daisuke@xxxxxxxxxxx>
> ---
> drivers/infiniband/sw/rxe/rxe_req.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/infiniband/sw/rxe/rxe_req.c b/drivers/infiniband/sw/rxe/rxe_req.c
> index 8e50d116d273..65134a9aefe7 100644
> --- a/drivers/infiniband/sw/rxe/rxe_req.c
> +++ b/drivers/infiniband/sw/rxe/rxe_req.c
> @@ -180,13 +180,13 @@ static struct rxe_send_wqe *req_next_wqe(struct rxe_qp *qp)
> if (wqe == NULL)
> return NULL;
>
> - spin_lock(&qp->state_lock);
> + spin_lock_bh(&qp->state_lock);
> if (unlikely((qp_state(qp) == IB_QPS_SQD) &&
> (wqe->state != wqe_state_processing))) {
> - spin_unlock(&qp->state_lock);
> + spin_unlock_bh(&qp->state_lock);
> return NULL;
> }
> - spin_unlock(&qp->state_lock);
> + spin_unlock_bh(&qp->state_lock);
>
> wqe->mask = wr_opcode_mask(wqe->wr.opcode, qp);
> return wqe;
> --
> 2.39.1
>
