From: Alex Estrin <alex.estrin@xxxxxxxxx> Per the IBTA spec, QP destroy shall fail if the QP is attached to multicast groups, although the spec is silent on modify_qp to reset state. It implies that ULP must deregister QP from all mcast groups for destroy to succeed. The faulty patch "IB/ipoib: Update broadcast object if PKey value was changed in index 0" exposed two issues in rdmavt: 1. Rvt QP reset waits for qp references to go to zero. This will hang if QP is attached to multicast groups. 2. The mcast group detach will fail for a QP in reset state therefore preventing ULP from correcting the issue. This patch moves the reference count wait to the the destroy QP path and allows a QP mcast detach to work in the reset state. Reviewed-by: Mike Marciniszyn <mike.marciniszyn@xxxxxxxxx> Signed-off-by: Alex Estrin <alex.estrin@xxxxxxxxx> Signed-off-by: Dennis Dalessandro <dennis.dalessandro@xxxxxxxxx> --- drivers/infiniband/sw/rdmavt/mcast.c | 2 +- drivers/infiniband/sw/rdmavt/qp.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/infiniband/sw/rdmavt/mcast.c b/drivers/infiniband/sw/rdmavt/mcast.c index 1f12b69..b3a38c5 100644 --- a/drivers/infiniband/sw/rdmavt/mcast.c +++ b/drivers/infiniband/sw/rdmavt/mcast.c @@ -351,7 +351,7 @@ int rvt_detach_mcast(struct ib_qp *ibqp, union ib_gid *gid, u16 lid) int last = 0; int ret = 0; - if (ibqp->qp_num <= 1 || qp->state == IB_QPS_RESET) + if (ibqp->qp_num <= 1) return -EINVAL; spin_lock_irq(&ibp->lock); diff --git a/drivers/infiniband/sw/rdmavt/qp.c b/drivers/infiniband/sw/rdmavt/qp.c index 22df09a..367c786 100644 --- a/drivers/infiniband/sw/rdmavt/qp.c +++ b/drivers/infiniband/sw/rdmavt/qp.c @@ -717,7 +717,6 @@ static void rvt_reset_qp(struct rvt_dev_info *rdi, struct rvt_qp *qp, /* take qp out the hash and wait for it to be unused */ rvt_remove_qp(rdi, qp); - wait_event(qp->wait, !atomic_read(&qp->refcount)); /* grab the lock b/c it was locked at call time */ spin_lock_irq(&qp->r_lock); @@ -1443,6 +1442,7 @@ int rvt_destroy_qp(struct ib_qp *ibqp) spin_unlock(&qp->s_hlock); spin_unlock_irq(&qp->r_lock); + wait_event(qp->wait, !atomic_read(&qp->refcount)); /* qpn is now available for use again */ rvt_free_qpn(&rdi->qp_dev->qpn_table, qp->ibqp.qp_num); -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
