[PATCH for-rc] RDMA/erdma: Use IRQ-safe XArray helpers for QP and CQ tables

Cheng Xu <[email protected]>
Newsgroups org.kernel.vger.linux-rdma
Message-ID <[email protected]>
Locked QP and CQ lookups from EQ interrupts can deadlock with
create-path XArray updates. If an interrupt arrives while the create
path holds the plain xa_lock, the lookup spins forever trying to
acquire the same lock.

Use IRQ-safe XArray helpers for all QP and CQ create-path updates,
including the GSI QP store and error paths.

Fixes: 98df2aee1459 ("RDMA/erdma: Hold CQ references when processing EQ events")
Fixes: a52eeff32024 ("RDMA/erdma: Hold QP references for AE and CM processing")
Signed-off-by: Cheng Xu <[email protected]>
---
 drivers/infiniband/hw/erdma/erdma_verbs.c | 18 +++++++++---------
 1 file changed, 9 insertions(+), 9 deletions(-)

diff --git a/drivers/infiniband/hw/erdma/erdma_verbs.c b/drivers/infiniband/hw/erdma/erdma_verbs.c
index 65b1af1e6623..f18b88bba281 100644
--- a/drivers/infiniband/hw/erdma/erdma_verbs.c
+++ b/drivers/infiniband/hw/erdma/erdma_verbs.c
@@ -1021,15 +1021,15 @@ int erdma_create_qp(struct ib_qp *ibqp, struct ib_qp_init_attr *attrs,
 	init_completion(&qp->safe_free);
 
 	if (qp->ibqp.qp_type == IB_QPT_GSI) {
-		old_entry = xa_store(&dev->qp_xa, 1, qp, GFP_KERNEL);
+		old_entry = xa_store_irq(&dev->qp_xa, 1, qp, GFP_KERNEL);
 		if (xa_is_err(old_entry))
 			ret = xa_err(old_entry);
 		else
 			qp->ibqp.qp_num = 1;
 	} else {
-		ret = xa_alloc_cyclic(&dev->qp_xa, &qp->ibqp.qp_num, qp,
-				      XA_LIMIT(1, dev->attrs.max_qp - 1),
-				      &dev->next_alloc_qpn, GFP_KERNEL);
+		ret = xa_alloc_cyclic_irq(&dev->qp_xa, &qp->ibqp.qp_num, qp,
+					  XA_LIMIT(1, dev->attrs.max_qp - 1),
+					  &dev->next_alloc_qpn, GFP_KERNEL);
 	}
 
 	if (ret < 0) {
@@ -1089,7 +1089,7 @@ int erdma_create_qp(struct ib_qp *ibqp, struct ib_qp_init_attr *attrs,
 	else
 		free_kernel_qp(qp);
 err_out_xa:
-	xa_erase(&dev->qp_xa, QP_ID(qp));
+	xa_erase_irq(&dev->qp_xa, QP_ID(qp));
 err_out:
 	return ret;
 }
@@ -1993,9 +1993,9 @@ int erdma_create_cq(struct ib_cq *ibcq, const struct ib_cq_init_attr *attr,
 	refcount_set(&cq->refcount, 1);
 	init_completion(&cq->free);
 
-	ret = xa_alloc_cyclic(&dev->cq_xa, &cq->cqn, cq,
-			      XA_LIMIT(1, dev->attrs.max_cq - 1),
-			      &dev->next_alloc_cqn, GFP_KERNEL);
+	ret = xa_alloc_cyclic_irq(&dev->cq_xa, &cq->cqn, cq,
+				  XA_LIMIT(1, dev->attrs.max_cq - 1),
+				  &dev->next_alloc_cqn, GFP_KERNEL);
 	if (ret < 0)
 		return ret;
 
@@ -2041,7 +2041,7 @@ int erdma_create_cq(struct ib_cq *ibcq, const struct ib_cq_init_attr *attr,
 	}
 
 err_out_xa:
-	xa_erase(&dev->cq_xa, cq->cqn);
+	xa_erase_irq(&dev->cq_xa, cq->cqn);
 
 	return ret;
 }
-- 
2.31.1
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