Hi Leon, > On Sat, Aug 21, 2021 at 07:43:39AM +0000, Alok Prasad wrote: > > This patch fixes crash caused by querying qp. > > This is due the fact that when no traffic is running, > > rdma_create_qp hasn't created any qp hence qed->qp is null. > > This description is not correct, all QP creation flows > dev->ops->rdma_create_qp() is called and if qedr_create_qp() successes, > we will have valid qp->qed_qp pointer. > In qedr_create_qp(), first qp we create is GSI QP and it immediately returns after creating gsi_qp, and none of function either qedr_create_user_qp() nor qedr_create_kernel_qp() is called, both of them would have in turned called dev->ops->rdma_create_qp(), hence qp->qed_qp is null here. Anyway will send a v2 as kernel test robot reported one Enum Warning. > > > > Below call trace is generated while using iproute2 utility > > "rdma res show -dd qp" on rdma interface. > > > > ========================================================================== > > [ 302.569794] BUG: kernel NULL pointer dereference, address: 0000000000000034 > > .. > > [ 302.570378] Hardware name: Dell Inc. PowerEdge R720/0M1GCR, BIOS 1.2.6 05/10/2012 > > [ 302.570500] RIP: 0010:qed_rdma_query_qp+0x33/0x1a0 [qed] > > [ 302.570861] RSP: 0018:ffffba560a08f580 EFLAGS: 00010206 > > [ 302.570979] RAX: 0000000200000000 RBX: ffffba560a08f5b8 RCX: 0000000000000000 > > [ 302.571100] RDX: ffffba560a08f5b8 RSI: 0000000000000000 RDI: ffff9807ee458090 > > [ 302.571221] RBP: ffffba560a08f5a0 R08: 0000000000000000 R09: ffff9807890e7048 > > [ 302.571342] R10: ffffba560a08f658 R11: 0000000000000000 R12: 0000000000000000 > > [ 302.571462] R13: ffff9807ee458090 R14: ffff9807f0afb000 R15: ffffba560a08f7ec > > [ 302.571583] FS: 00007fbbf8bfe740(0000) GS:ffff980aafa00000(0000) > knlGS:0000000000000000 > > [ 302.571729] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > > [ 302.571847] CR2: 0000000000000034 CR3: 00000001720ba001 CR4: 00000000000606f0 > > [ 302.571968] Call Trace: > > [ 302.572083] qedr_query_qp+0x82/0x360 [qedr] > > [ 302.572211] ib_query_qp+0x34/0x40 [ib_core] > > [ 302.572361] ? ib_query_qp+0x34/0x40 [ib_core] > > [ 302.572503] fill_res_qp_entry_query.isra.26+0x47/0x1d0 [ib_core] > > [ 302.572670] ? __nla_put+0x20/0x30 > > [ 302.572788] ? nla_put+0x33/0x40 > > [ 302.572901] fill_res_qp_entry+0xe3/0x120 [ib_core] > > [ 302.573058] res_get_common_dumpit+0x3f8/0x5d0 [ib_core] > > [ 302.573213] ? fill_res_cm_id_entry+0x1f0/0x1f0 [ib_core] > > [ 302.573377] nldev_res_get_qp_dumpit+0x1a/0x20 [ib_core] > > [ 302.573529] netlink_dump+0x156/0x2f0 > > [ 302.573648] __netlink_dump_start+0x1ab/0x260 > > [ 302.573765] rdma_nl_rcv+0x1de/0x330 [ib_core] > > [ 302.573918] ? nldev_res_get_cm_id_dumpit+0x20/0x20 [ib_core] > > [ 302.574074] netlink_unicast+0x1b8/0x270 > > [ 302.574191] netlink_sendmsg+0x33e/0x470 > > [ 302.574307] sock_sendmsg+0x63/0x70 > > [ 302.574421] __sys_sendto+0x13f/0x180 > > [ 302.574536] ? setup_sgl.isra.12+0x70/0xc0 > > [ 302.574655] __x64_sys_sendto+0x28/0x30 > > [ 302.574769] do_syscall_64+0x3a/0xb0 > > [ 302.574884] entry_SYSCALL_64_after_hwframe+0x44/0xae > > ========================================================================== > > > > Signed-off-by: Ariel Elior <aelior@xxxxxxxxxxx> > > Signed-off-by: Shai Malin <smalin@xxxxxxxxxxx> > > Signed-off-by: Alok Prasad <palok@xxxxxxxxxxx> > > --- > > drivers/infiniband/hw/qedr/verbs.c | 17 +++++++++-------- > > 1 file changed, 9 insertions(+), 8 deletions(-) > > > > diff --git a/drivers/infiniband/hw/qedr/verbs.c b/drivers/infiniband/hw/qedr/verbs.c > > index fdc47ef7d861..79603e3fe2db 100644 > > --- a/drivers/infiniband/hw/qedr/verbs.c > > +++ b/drivers/infiniband/hw/qedr/verbs.c > > @@ -2758,15 +2758,18 @@ int qedr_query_qp(struct ib_qp *ibqp, > > int rc = 0; > > > > memset(¶ms, 0, sizeof(params)); > > - > > - rc = dev->ops->rdma_query_qp(dev->rdma_ctx, qp->qed_qp, ¶ms); > > - if (rc) > > - goto err; > > - > > At that point, QP should be valid. > > > memset(qp_attr, 0, sizeof(*qp_attr)); > > memset(qp_init_attr, 0, sizeof(*qp_init_attr)); > > > > - qp_attr->qp_state = qedr_get_ibqp_state(params.state); > > + if (qp->qed_qp) > > + rc = dev->ops->rdma_query_qp(dev->rdma_ctx, > > + qp->qed_qp, ¶ms); > > + > > + if (qp->qp_type == IB_QPT_GSI) > > + qp_attr->qp_state = QED_ROCE_QP_STATE_RTS; > > + else > > + qp_attr->qp_state = qedr_get_ibqp_state(params.state); > > + > > qp_attr->cur_qp_state = qedr_get_ibqp_state(params.state); > > qp_attr->path_mtu = ib_mtu_int_to_enum(params.mtu); > > qp_attr->path_mig_state = IB_MIG_MIGRATED; > > @@ -2810,8 +2813,6 @@ int qedr_query_qp(struct ib_qp *ibqp, > > > > DP_DEBUG(dev, QEDR_MSG_QP, "QEDR_QUERY_QP: max_inline_data=%d\n", > > qp_attr->cap.max_inline_data); > > - > > -err: > > return rc; > > } > > > > -- > > 2.17.1 > >
