[PATCH rdma-next 1/4] RDMA/irdma: Fix QP handle assignment for SRQ completions

[Jacob Moroni <jmoroni@google.com>]

The QP handle comes from a different location in the CQE depending
on whether it's an SRQ or normal completion. For normal SQ/RQ CQEs,
it comes from offset 8, but for SRQs, it comes from offset 40.

This was correctly handled when the QP handle was initially loaded
in irdma_uk_cq_poll_cmpl(), but there was a leftover re-load of
the QP handle later on in that function which unconditionally
loaded it from offset 8. This would result in a bogus QP handle
being used when processing SRQ completions.

Fix this by removing the extra QP handle load.

While at it, load the QP handle into the u64 comp_ctx and cast
it rather than loading directly into the QP pointer since this
could overflow on 32 bit systems.

Fixes: 563e1feb5f6e ("RDMA/irdma: Add SRQ support")
Signed-off-by: Jacob Moroni <jmoroni@google.com>
---
 drivers/infiniband/hw/irdma/uk.c | 9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/drivers/infiniband/hw/irdma/uk.c b/drivers/infiniband/hw/irdma/uk.c
index a34883fe9983..250267ef5727 100644
--- a/drivers/infiniband/hw/irdma/uk.c
+++ b/drivers/infiniband/hw/irdma/uk.c
@@ -1220,11 +1220,11 @@ int irdma_uk_cq_poll_cmpl(struct irdma_cq_uk *cq,
 	is_srq = (u8)FIELD_GET(IRDMA_CQ_SRQ, qword3);
 	info->error = (bool)FIELD_GET(IRDMA_CQ_ERROR, qword3);
 	info->ipv4 = (bool)FIELD_GET(IRDMACQ_IPV4, qword3);
-	get_64bit_val(cqe, 8, &comp_ctx);
 	if (is_srq)
-		get_64bit_val(cqe, 40, (u64 *)&qp);
+		get_64bit_val(cqe, 40, &comp_ctx);
 	else
-		qp = (struct irdma_qp_uk *)(unsigned long)comp_ctx;
+		get_64bit_val(cqe, 8, &comp_ctx);
+	qp = (struct irdma_qp_uk *)(unsigned long)comp_ctx;
 	if (info->error) {
 		info->major_err = FIELD_GET(IRDMA_CQ_MAJERR, qword3);
 		info->minor_err = FIELD_GET(IRDMA_CQ_MINERR, qword3);
@@ -1268,10 +1268,7 @@ int irdma_uk_cq_poll_cmpl(struct irdma_cq_uk *cq,
 	info->qp_id = (u32)FIELD_GET(IRDMACQ_QPID, qword2);
 	info->ud_src_qpn = (u32)FIELD_GET(IRDMACQ_UDSRCQPN, qword2);
 
-	get_64bit_val(cqe, 8, &comp_ctx);
-
 	info->solicited_event = (bool)FIELD_GET(IRDMACQ_SOEVENT, qword3);
-	qp = (struct irdma_qp_uk *)(unsigned long)comp_ctx;
 	if (!qp || qp->destroy_pending) {
 		ret_code = -EFAULT;
 		goto exit;
-- 
2.56.0.455.g6c5a503b38-goog