This is a note to let you know that I've just added the patch titled
RDMA/hns: Modify the value of MAX_LP_MSG_LEN to meet hardware compatibility
to the 5.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
rdma-hns-modify-the-value-of-max_lp_msg_len-to-meet-.patch
and it can be found in the queue-5.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit fa46bc035d48a9c29f43b6a1312adcb1bf980405
Author: Yixing Liu <liuyixing1@xxxxxxxxxx>
Date: Fri Oct 29 18:05:37 2021 +0800
RDMA/hns: Modify the value of MAX_LP_MSG_LEN to meet hardware compatibility
[ Upstream commit 0e60778efb072d47efc7100c4009b5bd97273b0b ]
The upper limit of MAX_LP_MSG_LEN on HIP08 is 64K, and the upper limit on
HIP09 is 16K. Regardless of whether it is HIP08 or HIP09, only 16K will be
used. In order to ensure compatibility, it is unified to 16K.
Setting MAX_LP_MSG_LEN to 16K will not cause performance loss on HIP08.
Fixes: fbed9d2be292 ("RDMA/hns: Fix configuration of ack_req_freq in QPC")
Link: https://lore.kernel.org/r/20211029100537.27299-1-liangwenpeng@xxxxxxxxxx
Signed-off-by: Yixing Liu <liuyixing1@xxxxxxxxxx>
Signed-off-by: Wenpeng Liang <liangwenpeng@xxxxxxxxxx>
Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/infiniband/hw/hns/hns_roce_hw_v2.c b/drivers/infiniband/hw/hns/hns_roce_hw_v2.c
index a77732c218dcb..e2547e8b4d21c 100644
--- a/drivers/infiniband/hw/hns/hns_roce_hw_v2.c
+++ b/drivers/infiniband/hw/hns/hns_roce_hw_v2.c
@@ -4413,8 +4413,8 @@ static int modify_qp_init_to_rtr(struct ib_qp *ibqp,
mtu = ib_mtu_enum_to_int(ib_mtu);
if (WARN_ON(mtu <= 0))
return -EINVAL;
-#define MAX_LP_MSG_LEN 65536
- /* MTU * (2 ^ LP_PKTN_INI) shouldn't be bigger than 64KB */
+#define MAX_LP_MSG_LEN 16384
+ /* MTU * (2 ^ LP_PKTN_INI) shouldn't be bigger than 16KB */
lp_pktn_ini = ilog2(MAX_LP_MSG_LEN / mtu);
if (WARN_ON(lp_pktn_ini >= 0xF))
return -EINVAL;
