[PATCH 5.13 560/800] RDMA/hns: Add a check to ensure integer mtu is positive

From: Greg Kroah-Hartman
Date: Mon Jul 12 2021 - 04:50:45 EST


From: Weihang Li <liweihang@xxxxxxxxxx>

[ Upstream commit fe331da0f210c60342b042a03fe53f1b564b412b ]

GCC may reports an running time assert error when a value calculated from
ib_mtu_enum_to_int() is using as 'val' in FIELD_PREDP:

include/linux/compiler_types.h:328:38: error: call to
'__compiletime_assert_1524' declared with attribute error: FIELD_PREP:
value too large for the field

So a check is added about whether integer mtu from ib_mtu_enum_to_int() is
negative to avoid this warning.

Link: https://lore.kernel.org/r/1624262443-24528-3-git-send-email-liweihang@xxxxxxxxxx
Reported-by: kernel test robot <lkp@xxxxxxxxx>
Signed-off-by: Weihang Li <liweihang@xxxxxxxxxx>
Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/infiniband/hw/hns/hns_roce_hw_v2.c | 15 ++++++++++-----
1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/drivers/infiniband/hw/hns/hns_roce_hw_v2.c b/drivers/infiniband/hw/hns/hns_roce_hw_v2.c
index cd58becf1baf..f074e2e5a5c8 100644
--- a/drivers/infiniband/hw/hns/hns_roce_hw_v2.c
+++ b/drivers/infiniband/hw/hns/hns_roce_hw_v2.c
@@ -4499,12 +4499,13 @@ static int modify_qp_init_to_rtr(struct ib_qp *ibqp,
struct ib_device *ibdev = &hr_dev->ib_dev;
dma_addr_t trrl_ba;
dma_addr_t irrl_ba;
- enum ib_mtu mtu;
+ enum ib_mtu ib_mtu;
u8 lp_pktn_ini;
u64 *mtts;
u8 *dmac;
u8 *smac;
u32 port;
+ int mtu;
int ret;

ret = config_qp_rq_buf(hr_dev, hr_qp, context, qpc_mask);
@@ -4588,19 +4589,23 @@ static int modify_qp_init_to_rtr(struct ib_qp *ibqp,
roce_set_field(qpc_mask->byte_52_udpspn_dmac, V2_QPC_BYTE_52_DMAC_M,
V2_QPC_BYTE_52_DMAC_S, 0);

- mtu = get_mtu(ibqp, attr);
- hr_qp->path_mtu = mtu;
+ ib_mtu = get_mtu(ibqp, attr);
+ hr_qp->path_mtu = ib_mtu;
+
+ mtu = ib_mtu_enum_to_int(ib_mtu);
+ if (WARN_ON(mtu < 0))
+ return -EINVAL;

if (attr_mask & IB_QP_PATH_MTU) {
roce_set_field(context->byte_24_mtu_tc, V2_QPC_BYTE_24_MTU_M,
- V2_QPC_BYTE_24_MTU_S, mtu);
+ V2_QPC_BYTE_24_MTU_S, ib_mtu);
roce_set_field(qpc_mask->byte_24_mtu_tc, V2_QPC_BYTE_24_MTU_M,
V2_QPC_BYTE_24_MTU_S, 0);
}

#define MAX_LP_MSG_LEN 65536
/* MTU * (2 ^ LP_PKTN_INI) shouldn't be bigger than 64KB */
- lp_pktn_ini = ilog2(MAX_LP_MSG_LEN / ib_mtu_enum_to_int(mtu));
+ lp_pktn_ini = ilog2(MAX_LP_MSG_LEN / mtu);

roce_set_field(context->byte_56_dqpn_err, V2_QPC_BYTE_56_LP_PKTN_INI_M,
V2_QPC_BYTE_56_LP_PKTN_INI_S, lp_pktn_ini);
--
2.30.2