From b024dd0eba6e6d568f69d63c5e3153aba94c23e3 Mon Sep 17 00:00:00 2001
From: Chuck Lever <chuck.lever@oracle.com>
Date: Sun, 25 Nov 2018 17:13:08 -0500
Subject: [PATCH 1/1] rxe: IB_WR_REG_MR does not capture MR's iova field
Git-commit: b024dd0eba6e6d568f69d63c5e3153aba94c23e3
Patch-mainline: v5.0-rc1
References: git-fixes

FRWR memory registration is done with a series of calls and WRs.
1. ULP invokes ib_dma_map_sg()
2. ULP invokes ib_map_mr_sg()
3. ULP posts an IB_WR_REG_MR on the Send queue

Step 2 generates an iova. It is permissible for ULPs to change this
iova (with certain restrictions) between steps 2 and 3.

rxe_map_mr_sg captures the MR's iova but later when rxe processes the
REG_MR WR, it ignores the MR's iova field. If a ULP alters the MR's iova
after step 2 but before step 3, rxe never captures that change.

When the remote sends an RDMA Read targeting that MR, rxe looks up the
R_key, but the altered iova does not match the iova stored in the MR,
causing the RDMA Read request to fail.

Reported-by: Anna Schumaker <schumaker.anna@gmail.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Acked-by: Nicolas Morey <nmorey@suse.com>
---
 drivers/infiniband/sw/rxe/rxe_req.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/infiniband/sw/rxe/rxe_req.c b/drivers/infiniband/sw/rxe/rxe_req.c
index b546721efbfe..c5d9b558fa90 100644
--- a/drivers/infiniband/sw/rxe/rxe_req.c
+++ b/drivers/infiniband/sw/rxe/rxe_req.c
@@ -643,6 +643,7 @@ next_wqe:
 			rmr->access = wqe->wr.wr.reg.access;
 			rmr->lkey = wqe->wr.wr.reg.key;
 			rmr->rkey = wqe->wr.wr.reg.key;
+			rmr->iova = wqe->wr.wr.reg.mr->iova;
 			wqe->state = wqe_state_done;
 			wqe->status = IB_WC_SUCCESS;
 		} else {
-- 
2.39.1.1.gbe015eda0162