iw_cxgb4: add referencing to wait objects

For messages sent from the host to fw that solicit a reply from fw,
the c4iw_wr_wait struct pointer is passed in the host->fw message, and
included in the fw->host fw6_msg reply.  This allows the sender to wait
until the reply is received, and the code processing the ingress reply
to wake up the sender.

If c4iw_wait_for_reply() times out, however, we need to keep the
c4iw_wr_wait object around in case the reply eventually does arrive.
Otherwise we have touch-after-free bugs in the wake_up paths.

This was hit due to a bad kernel driver that blocked ingress processing
of cxgb4 for a long time, causing iw_cxgb4 timeouts, but eventually
resuming ingress processing and thus hitting the touch-after-free bug.

So I want to fix iw_cxgb4 such that we'll at least keep the wait object
around until the reply comes.  If it never comes we leak a small amount of
memory, but if it does come late, we won't potentially crash the system.

So add a kref struct in the c4iw_wr_wait struct, and take a reference
before sending a message to FW that will generate a FW6 reply.  And remove
the reference (and potentially free the wait object) when the reply
is processed.

The ep code also uses the wr_wait for non FW6 CPL messages and doesn't
embed the c4iw_wr_wait object in the message sent to firmware.  So for
those cases we add c4iw_wake_up_noref().

The mr/mw, cq, and qp object create/destroy paths do need this reference
logic.  For these paths, c4iw_ref_send_wait() is introduced to take the
wr_wait reference, send the msg to fw, and then wait for the reply.

So going forward, iw_cxgb4 either uses c4iw_ofld_send(),
c4iw_wait_for_reply() and c4iw_wake_up_noref() like is done in the some
of the endpoint logic, or c4iw_ref_send_wait() and c4iw_wake_up_deref()
(formerly c4iw_wake_up()) when sending messages with the c4iw_wr_wait
object pointer embedded in the message and resulting FW6 reply.
Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

drivers/infiniband/hw/cxgb4/cm.c

@@ -318,7 +318,7 @@ static void *alloc_ep(int size, gfp_t gfp)
 
 	epc = kzalloc(size, gfp);
 	if (epc) {
-		epc->wr_waitp = kzalloc(sizeof(*epc->wr_waitp), gfp);
+		epc->wr_waitp = c4iw_alloc_wr_wait(gfp);
 		if (!epc->wr_waitp) {
 			kfree(epc);
 			epc = NULL;
@@ -414,7 +414,7 @@ void _c4iw_free_ep(struct kref *kref)
 	}
 	if (!skb_queue_empty(&ep->com.ep_skb_list))
 		skb_queue_purge(&ep->com.ep_skb_list);
-	kfree(ep->com.wr_waitp);
+	c4iw_put_wr_wait(ep->com.wr_waitp);
 	kfree(ep);
 }
 
@@ -1880,7 +1880,7 @@ static int abort_rpl(struct c4iw_dev *dev, struct sk_buff *skb)
 	mutex_lock(&ep->com.mutex);
 	switch (ep->com.state) {
 	case ABORTING:
-		c4iw_wake_up(ep->com.wr_waitp, -ECONNRESET);
+		c4iw_wake_up_noref(ep->com.wr_waitp, -ECONNRESET);
 		__state_set(&ep->com, DEAD);
 		release = 1;
 		break;
@@ -2327,7 +2327,7 @@ static int pass_open_rpl(struct c4iw_dev *dev, struct sk_buff *skb)
 	}
 	pr_debug("ep %p status %d error %d\n", ep,
 		 rpl->status, status2errno(rpl->status));
-	c4iw_wake_up(ep->com.wr_waitp, status2errno(rpl->status));
+	c4iw_wake_up_noref(ep->com.wr_waitp, status2errno(rpl->status));
 	c4iw_put_ep(&ep->com);
 out:
 	return 0;
@@ -2344,7 +2344,7 @@ static int close_listsrv_rpl(struct c4iw_dev *dev, struct sk_buff *skb)
 		goto out;
 	}
 	pr_debug("ep %p\n", ep);
-	c4iw_wake_up(ep->com.wr_waitp, status2errno(rpl->status));
+	c4iw_wake_up_noref(ep->com.wr_waitp, status2errno(rpl->status));
 	c4iw_put_ep(&ep->com);
 out:
 	return 0;
@@ -2679,12 +2679,12 @@ static int peer_close(struct c4iw_dev *dev, struct sk_buff *skb)
 		 */
 		__state_set(&ep->com, CLOSING);
 		pr_debug("waking up ep %p tid %u\n", ep, ep->hwtid);
-		c4iw_wake_up(ep->com.wr_waitp, -ECONNRESET);
+		c4iw_wake_up_noref(ep->com.wr_waitp, -ECONNRESET);
 		break;
 	case MPA_REP_SENT:
 		__state_set(&ep->com, CLOSING);
 		pr_debug("waking up ep %p tid %u\n", ep, ep->hwtid);
-		c4iw_wake_up(ep->com.wr_waitp, -ECONNRESET);
+		c4iw_wake_up_noref(ep->com.wr_waitp, -ECONNRESET);
 		break;
 	case FPDU_MODE:
 		start_ep_timer(ep);
@@ -2766,7 +2766,7 @@ static int peer_abort(struct c4iw_dev *dev, struct sk_buff *skb)
 	 * MPA_REQ_SENT
 	 */
 	if (ep->com.state != MPA_REQ_SENT)
-		c4iw_wake_up(ep->com.wr_waitp, -ECONNRESET);
+		c4iw_wake_up_noref(ep->com.wr_waitp, -ECONNRESET);
 
 	mutex_lock(&ep->com.mutex);
 	switch (ep->com.state) {
@@ -4187,7 +4187,7 @@ static int fw6_msg(struct c4iw_dev *dev, struct sk_buff *skb)
 		wr_waitp = (struct c4iw_wr_wait *)(__force unsigned long) rpl->data[1];
 		pr_debug("wr_waitp %p ret %u\n", wr_waitp, ret);
 		if (wr_waitp)
-			c4iw_wake_up(wr_waitp, ret ? -ret : 0);
+			c4iw_wake_up_deref(wr_waitp, ret ? -ret : 0);
 		kfree_skb(skb);
 		break;
 	case FW6_TYPE_CQE:
@@ -4224,7 +4224,7 @@ static int peer_abort_intr(struct c4iw_dev *dev, struct sk_buff *skb)
 	}
 	pr_debug("ep %p tid %u state %u\n", ep, ep->hwtid, ep->com.state);
 
-	c4iw_wake_up(ep->com.wr_waitp, -ECONNRESET);
+	c4iw_wake_up_noref(ep->com.wr_waitp, -ECONNRESET);
 out:
 	sched(dev, skb);
 	return 0;

drivers/infiniband/hw/cxgb4/cq.c

@@ -57,10 +57,7 @@ static int destroy_cq(struct c4iw_rdev *rdev, struct t4_cq *cq,
 	res->u.cq.iqid = cpu_to_be32(cq->cqid);
 
 	c4iw_init_wr_wait(wr_waitp);
-	ret = c4iw_ofld_send(rdev, skb);
-	if (!ret) {
-		ret = c4iw_wait_for_reply(rdev, wr_waitp, 0, 0, __func__);
-	}
+	ret = c4iw_ref_send_wait(rdev, skb, wr_waitp, 0, 0, __func__);
 
 	kfree(cq->sw_queue);
 	dma_free_coherent(&(rdev->lldi.pdev->dev),
@@ -140,12 +137,7 @@ static int create_cq(struct c4iw_rdev *rdev, struct t4_cq *cq,
 	res->u.cq.iqaddr = cpu_to_be64(cq->dma_addr);
 
 	c4iw_init_wr_wait(wr_waitp);
-
-	ret = c4iw_ofld_send(rdev, skb);
-	if (ret)
-		goto err4;
-	pr_debug("wait_event wr_wait %p\n", wr_waitp);
-	ret = c4iw_wait_for_reply(rdev, wr_waitp, 0, 0, __func__);
+	ret = c4iw_ref_send_wait(rdev, skb, wr_waitp, 0, 0, __func__);
 	if (ret)
 		goto err4;
 
@@ -869,7 +861,7 @@ int c4iw_destroy_cq(struct ib_cq *ib_cq)
 	destroy_cq(&chp->rhp->rdev, &chp->cq,
 		   ucontext ? &ucontext->uctx : &chp->cq.rdev->uctx,
 		   chp->destroy_skb, chp->wr_waitp);
-	kfree(chp->wr_waitp);
+	c4iw_put_wr_wait(chp->wr_waitp);
 	kfree(chp);
 	return 0;
 }
@@ -901,7 +893,7 @@ struct ib_cq *c4iw_create_cq(struct ib_device *ibdev,
 	chp = kzalloc(sizeof(*chp), GFP_KERNEL);
 	if (!chp)
 		return ERR_PTR(-ENOMEM);
-	chp->wr_waitp = kzalloc(sizeof(*chp->wr_waitp), GFP_KERNEL);
+	chp->wr_waitp = c4iw_alloc_wr_wait(GFP_KERNEL);
 	if (!chp->wr_waitp) {
 		ret = -ENOMEM;
 		goto err_free_chp;
@@ -1020,7 +1012,7 @@ struct ib_cq *c4iw_create_cq(struct ib_device *ibdev,
 err_free_skb:
 	kfree_skb(chp->destroy_skb);
 err_free_wr_wait:
-	kfree(chp->wr_waitp);
+	c4iw_put_wr_wait(chp->wr_waitp);
 err_free_chp:
 	kfree(chp);
 	return ERR_PTR(ret);

drivers/infiniband/hw/cxgb4/device.c

@@ -1518,6 +1518,27 @@ static struct cxgb4_uld_info c4iw_uld_info = {
 	.control = c4iw_uld_control,
 };
 
+void _c4iw_free_wr_wait(struct kref *kref)
+{
+	struct c4iw_wr_wait *wr_waitp;
+
+	wr_waitp = container_of(kref, struct c4iw_wr_wait, kref);
+	pr_debug("Free wr_wait %p\n", wr_waitp);
+	kfree(wr_waitp);
+}
+
+struct c4iw_wr_wait *c4iw_alloc_wr_wait(gfp_t gfp)
+{
+	struct c4iw_wr_wait *wr_waitp;
+
+	wr_waitp = kzalloc(sizeof(*wr_waitp), gfp);
+	if (wr_waitp) {
+		kref_init(&wr_waitp->kref);
+		pr_debug("wr_wait %p\n", wr_waitp);
+	}
+	return wr_waitp;
+}
+
 static int __init c4iw_init_module(void)
 {
 	int err;

drivers/infiniband/hw/cxgb4/iw_cxgb4.h

@@ -202,18 +202,50 @@ static inline int c4iw_num_stags(struct c4iw_rdev *rdev)
 struct c4iw_wr_wait {
 	struct completion completion;
 	int ret;
+	struct kref kref;
 };
 
+void _c4iw_free_wr_wait(struct kref *kref);
+
+static inline void c4iw_put_wr_wait(struct c4iw_wr_wait *wr_waitp)
+{
+	pr_debug("wr_wait %p ref before put %u\n", wr_waitp,
+		 kref_read(&wr_waitp->kref));
+	WARN_ON(kref_read(&wr_waitp->kref) == 0);
+	kref_put(&wr_waitp->kref, _c4iw_free_wr_wait);
+}
+
+static inline void c4iw_get_wr_wait(struct c4iw_wr_wait *wr_waitp)
+{
+	pr_debug("wr_wait %p ref before get %u\n", wr_waitp,
+		 kref_read(&wr_waitp->kref));
+	WARN_ON(kref_read(&wr_waitp->kref) == 0);
+	kref_get(&wr_waitp->kref);
+}
+
 static inline void c4iw_init_wr_wait(struct c4iw_wr_wait *wr_waitp)
 {
 	wr_waitp->ret = 0;
 	init_completion(&wr_waitp->completion);
 }
 
-static inline void c4iw_wake_up(struct c4iw_wr_wait *wr_waitp, int ret)
+static inline void _c4iw_wake_up(struct c4iw_wr_wait *wr_waitp, int ret,
+				 bool deref)
 {
 	wr_waitp->ret = ret;
 	complete(&wr_waitp->completion);
+	if (deref)
+		c4iw_put_wr_wait(wr_waitp);
+}
+
+static inline void c4iw_wake_up_noref(struct c4iw_wr_wait *wr_waitp, int ret)
+{
+	_c4iw_wake_up(wr_waitp, ret, false);
+}
+
+static inline void c4iw_wake_up_deref(struct c4iw_wr_wait *wr_waitp, int ret)
+{
+	_c4iw_wake_up(wr_waitp, ret, true);
 }
 
 static inline int c4iw_wait_for_reply(struct c4iw_rdev *rdev,
@@ -234,14 +266,36 @@ static inline int c4iw_wait_for_reply(struct c4iw_rdev *rdev,
 		       func, pci_name(rdev->lldi.pdev), hwtid, qpid);
 		rdev->flags |= T4_FATAL_ERROR;
 		wr_waitp->ret = -EIO;
+		goto out;
 	}
-out:
 	if (wr_waitp->ret)
 		pr_debug("%s: FW reply %d tid %u qpid %u\n",
 			 pci_name(rdev->lldi.pdev), wr_waitp->ret, hwtid, qpid);
+out:
 	return wr_waitp->ret;
 }
 
+int c4iw_ofld_send(struct c4iw_rdev *rdev, struct sk_buff *skb);
+
+static inline int c4iw_ref_send_wait(struct c4iw_rdev *rdev,
+				     struct sk_buff *skb,
+				     struct c4iw_wr_wait *wr_waitp,
+				     u32 hwtid, u32 qpid,
+				     const char *func)
+{
+	int ret;
+
+	pr_debug("%s wr_wait %p hwtid %u qpid %u\n", func, wr_waitp, hwtid,
+		 qpid);
+	c4iw_get_wr_wait(wr_waitp);
+	ret = c4iw_ofld_send(rdev, skb);
+	if (ret) {
+		c4iw_put_wr_wait(wr_waitp);
+		return ret;
+	}
+	return c4iw_wait_for_reply(rdev, wr_waitp, hwtid, qpid, func);
+}
+
 enum db_state {
 	NORMAL = 0,
 	FLOW_CONTROL = 1,
@@ -991,7 +1045,6 @@ u32 c4iw_pblpool_alloc(struct c4iw_rdev *rdev, int size);
 void c4iw_pblpool_free(struct c4iw_rdev *rdev, u32 addr, int size);
 u32 c4iw_ocqp_pool_alloc(struct c4iw_rdev *rdev, int size);
 void c4iw_ocqp_pool_free(struct c4iw_rdev *rdev, u32 addr, int size);
-int c4iw_ofld_send(struct c4iw_rdev *rdev, struct sk_buff *skb);
 void c4iw_flush_hw_cq(struct c4iw_cq *chp);
 void c4iw_count_rcqes(struct t4_cq *cq, struct t4_wq *wq, int *count);
 int c4iw_ep_disconnect(struct c4iw_ep *ep, int abrupt, gfp_t gfp);
@@ -1019,5 +1072,6 @@ extern int db_fc_threshold;
 extern int db_coalescing_threshold;
 extern int use_dsgl;
 void c4iw_invalidate_mr(struct c4iw_dev *rhp, u32 rkey);
+struct c4iw_wr_wait *c4iw_alloc_wr_wait(gfp_t gfp);
 
 #endif

drivers/infiniband/hw/cxgb4/mem.c

@@ -100,11 +100,10 @@ static int _c4iw_write_mem_dma_aligned(struct c4iw_rdev *rdev, u32 addr,
 	sgl->len0 = cpu_to_be32(len);
 	sgl->addr0 = cpu_to_be64(data);
 
-	ret = c4iw_ofld_send(rdev, skb);
-	if (ret)
-		return ret;
 	if (wr_waitp)
-		ret = c4iw_wait_for_reply(rdev, wr_waitp, 0, 0, __func__);
+		ret = c4iw_ref_send_wait(rdev, skb, wr_waitp, 0, 0, __func__);
+	else
+		ret = c4iw_ofld_send(rdev, skb);
 	return ret;
 }
 
@@ -173,14 +172,17 @@ static int _c4iw_write_mem_inline(struct c4iw_rdev *rdev, u32 addr, u32 len,
 		if (copy_len % T4_ULPTX_MIN_IO)
 			memset(to_dp + copy_len, 0, T4_ULPTX_MIN_IO -
 			       (copy_len % T4_ULPTX_MIN_IO));
+		if (i == (num_wqe-1))
+			ret = c4iw_ref_send_wait(rdev, skb, wr_waitp, 0, 0,
+						 __func__);
+		else
 			ret = c4iw_ofld_send(rdev, skb);
-		skb = NULL;
 		if (ret)
-			return ret;
+			break;
+		skb = NULL;
 		len -= C4IW_MAX_INLINE_SIZE;
 	}
 
-	ret = c4iw_wait_for_reply(rdev, wr_waitp, 0, 0, __func__);
 	return ret;
 }
 
@@ -447,7 +449,7 @@ struct ib_mr *c4iw_get_dma_mr(struct ib_pd *pd, int acc)
 	mhp = kzalloc(sizeof(*mhp), GFP_KERNEL);
 	if (!mhp)
 		return ERR_PTR(-ENOMEM);
-	mhp->wr_waitp = kzalloc(sizeof(*mhp->wr_waitp), GFP_KERNEL);
+	mhp->wr_waitp = c4iw_alloc_wr_wait(GFP_KERNEL);
 	if (!mhp->wr_waitp) {
 		ret = -ENOMEM;
 		goto err_free_mhp;
@@ -485,7 +487,7 @@ struct ib_mr *c4iw_get_dma_mr(struct ib_pd *pd, int acc)
 	dereg_mem(&rhp->rdev, mhp->attr.stag, mhp->attr.pbl_size,
 		  mhp->attr.pbl_addr, mhp->dereg_skb, mhp->wr_waitp);
 err_free_wr_wait:
-	kfree(mhp->wr_waitp);
+	c4iw_put_wr_wait(mhp->wr_waitp);
 err_free_skb:
 	kfree_skb(mhp->dereg_skb);
 err_free_mhp:
@@ -522,7 +524,7 @@ struct ib_mr *c4iw_reg_user_mr(struct ib_pd *pd, u64 start, u64 length,
 	mhp = kzalloc(sizeof(*mhp), GFP_KERNEL);
 	if (!mhp)
 		return ERR_PTR(-ENOMEM);
-	mhp->wr_waitp = kzalloc(sizeof(*mhp->wr_waitp), GFP_KERNEL);
+	mhp->wr_waitp = c4iw_alloc_wr_wait(GFP_KERNEL);
 	if (!mhp->wr_waitp)
 		goto err_free_mhp;
 
@@ -600,7 +602,7 @@ struct ib_mr *c4iw_reg_user_mr(struct ib_pd *pd, u64 start, u64 length,
 err_free_skb:
 	kfree_skb(mhp->dereg_skb);
 err_free_wr_wait:
-	kfree(mhp->wr_waitp);
+	c4iw_put_wr_wait(mhp->wr_waitp);
 err_free_mhp:
 	kfree(mhp);
 	return ERR_PTR(err);
@@ -625,7 +627,7 @@ struct ib_mw *c4iw_alloc_mw(struct ib_pd *pd, enum ib_mw_type type,
 	if (!mhp)
 		return ERR_PTR(-ENOMEM);
 
-	mhp->wr_waitp = kzalloc(sizeof(*mhp->wr_waitp), GFP_KERNEL);
+	mhp->wr_waitp = c4iw_alloc_wr_wait(GFP_KERNEL);
 	if (!mhp->wr_waitp) {
 		ret = -ENOMEM;
 		goto free_mhp;
@@ -659,7 +661,7 @@ struct ib_mw *c4iw_alloc_mw(struct ib_pd *pd, enum ib_mw_type type,
 free_skb:
 	kfree_skb(mhp->dereg_skb);
 free_wr_wait:
-	kfree(mhp->wr_waitp);
+	c4iw_put_wr_wait(mhp->wr_waitp);
 free_mhp:
 	kfree(mhp);
 	return ERR_PTR(ret);
@@ -678,7 +680,7 @@ int c4iw_dealloc_mw(struct ib_mw *mw)
 	deallocate_window(&rhp->rdev, mhp->attr.stag, mhp->dereg_skb,
 			  mhp->wr_waitp);
 	kfree_skb(mhp->dereg_skb);
-	kfree(mhp->wr_waitp);
+	c4iw_put_wr_wait(mhp->wr_waitp);
 	kfree(mhp);
 	pr_debug("ib_mw %p mmid 0x%x ptr %p\n", mw, mmid, mhp);
 	return 0;
@@ -710,7 +712,7 @@ struct ib_mr *c4iw_alloc_mr(struct ib_pd *pd,
 		goto err;
 	}
 
-	mhp->wr_waitp = kzalloc(sizeof(*mhp->wr_waitp), GFP_KERNEL);
+	mhp->wr_waitp = c4iw_alloc_wr_wait(GFP_KERNEL);
 	if (!mhp->wr_waitp) {
 		ret = -ENOMEM;
 		goto err_free_mhp;
@@ -758,7 +760,7 @@ struct ib_mr *c4iw_alloc_mr(struct ib_pd *pd,
 	dma_free_coherent(&mhp->rhp->rdev.lldi.pdev->dev,
 			  mhp->max_mpl_len, mhp->mpl, mhp->mpl_addr);
 err_free_wr_wait:
-	kfree(mhp->wr_waitp);
+	c4iw_put_wr_wait(mhp->wr_waitp);
 err_free_mhp:
 	kfree(mhp);
 err:
@@ -812,7 +814,7 @@ int c4iw_dereg_mr(struct ib_mr *ib_mr)
 	if (mhp->umem)
 		ib_umem_release(mhp->umem);
 	pr_debug("mmid 0x%x ptr %p\n", mmid, mhp);
-	kfree(mhp->wr_waitp);
+	c4iw_put_wr_wait(mhp->wr_waitp);
 	kfree(mhp);
 	return 0;
 }

drivers/infiniband/hw/cxgb4/qp.c

@@ -353,11 +353,7 @@ static int create_qp(struct c4iw_rdev *rdev, struct t4_wq *wq,
 	res->u.sqrq.eqaddr = cpu_to_be64(wq->rq.dma_addr);
 
 	c4iw_init_wr_wait(wr_waitp);
-
-	ret = c4iw_ofld_send(rdev, skb);
-	if (ret)
-		goto free_dma;
-	ret = c4iw_wait_for_reply(rdev, wr_waitp, 0, wq->sq.qid, __func__);
+	ret = c4iw_ref_send_wait(rdev, skb, wr_waitp, 0, wq->sq.qid, __func__);
 	if (ret)
 		goto free_dma;
 
@@ -730,7 +726,7 @@ static void free_qp_work(struct work_struct *work)
 
 	if (ucontext)
 		c4iw_put_ucontext(ucontext);
-	kfree(qhp->wr_waitp);
+	c4iw_put_wr_wait(qhp->wr_waitp);
 	kfree(qhp);
 }
 
@@ -1358,13 +1354,10 @@ static int rdma_fini(struct c4iw_dev *rhp, struct c4iw_qp *qhp,
 	wqe->cookie = (uintptr_t)ep->com.wr_waitp;
 
 	wqe->u.fini.type = FW_RI_TYPE_FINI;
-	ret = c4iw_ofld_send(&rhp->rdev, skb);
-	if (ret)
-		goto out;
 
-	ret = c4iw_wait_for_reply(&rhp->rdev, ep->com.wr_waitp, qhp->ep->hwtid,
-			     qhp->wq.sq.qid, __func__);
-out:
+	ret = c4iw_ref_send_wait(&rhp->rdev, skb, ep->com.wr_waitp,
+				 qhp->ep->hwtid, qhp->wq.sq.qid, __func__);
+
 	pr_debug("ret %d\n", ret);
 	return ret;
 }
@@ -1462,15 +1455,11 @@ static int rdma_init(struct c4iw_dev *rhp, struct c4iw_qp *qhp)
 	if (qhp->attr.mpa_attr.initiator)
 		build_rtr_msg(qhp->attr.mpa_attr.p2p_type, &wqe->u.init);
 
-	ret = c4iw_ofld_send(&rhp->rdev, skb);
-	if (ret)
-		goto err1;
-
-	ret = c4iw_wait_for_reply(&rhp->rdev, qhp->ep->com.wr_waitp,
+	ret = c4iw_ref_send_wait(&rhp->rdev, skb, qhp->ep->com.wr_waitp,
 				 qhp->ep->hwtid, qhp->wq.sq.qid, __func__);
 	if (!ret)
 		goto out;
-err1:
+
 	free_ird(rhp, qhp->attr.max_ird);
 out:
 	pr_debug("ret %d\n", ret);
@@ -1796,7 +1785,7 @@ struct ib_qp *c4iw_create_qp(struct ib_pd *pd, struct ib_qp_init_attr *attrs,
 	if (!qhp)
 		return ERR_PTR(-ENOMEM);
 
-	qhp->wr_waitp = kzalloc(sizeof(*qhp), GFP_KERNEL);
+	qhp->wr_waitp = c4iw_alloc_wr_wait(GFP_KERNEL);
 	if (!qhp->wr_waitp) {
 		ret = -ENOMEM;
 		goto err_free_qhp;
@@ -1963,7 +1952,7 @@ struct ib_qp *c4iw_create_qp(struct ib_pd *pd, struct ib_qp_init_attr *attrs,
 	destroy_qp(&rhp->rdev, &qhp->wq,
 		   ucontext ? &ucontext->uctx : &rhp->rdev.uctx);
 err_free_wr_wait:
-	kfree(qhp->wr_waitp);
+	c4iw_put_wr_wait(qhp->wr_waitp);
 err_free_qhp:
 	kfree(qhp);
 	return ERR_PTR(ret);