[dpdk-stable] patch 'net/i40e: fix buffer size alignment' has been queued to stable release 20.11.4

[Xueming Li]

Hi,

FYI, your patch has been queued to stable release 20.11.4

Note it hasn't been pushed to http://dpdk.org/browse/dpdk-stable yet.
It will be pushed if I get no objections before 11/12/21. So please
shout if anyone has objections.

Also note that after the patch there's a diff of the upstream commit vs the
patch applied to the branch. This will indicate if there was any rebasing
needed to apply to the stable branch. If there were code changes for rebasing
(ie: not only metadata diffs), please double check that the rebase was
correctly done.

Queued patches are on a temporary branch at:
https://github.com/steevenlee/dpdk

This queued commit can be viewed at:
https://github.com/steevenlee/dpdk/commit/4fc3c6504068afa28824113b0872f50e8ac4209a

Thanks.

Xueming Li <xuemingl at nvidia.com>

---
>From 4fc3c6504068afa28824113b0872f50e8ac4209a Mon Sep 17 00:00:00 2001
From: Qiming Chen <chenqiming_huawei at 163.com>
Date: Mon, 6 Sep 2021 15:00:14 +0800
Subject: [PATCH] net/i40e: fix buffer size alignment
Cc: Xueming Li <xuemingl at nvidia.com>

The RTE_ALIGN macro is aligned upwards. If the buf_size variable is not
aligned with 1 << I40E_RXQ_CTX_DBUFF_SHIFT, the rx_buf_len is larger than
the actual mbuf memory after the operation. When receiving the packet, if
the packet is larger than the configured buf_size, it will cause a memory
stepping event.

The patch uses the RTE_ALIGN_FLOOR down alignment macro to correct the
problem.

Fixes: c1715402df8f ("i40evf: fix jumbo frame support")
Cc: stable at dpdk.org

Signed-off-by: Qiming Chen <chenqiming_huawei at 163.com>
---
 drivers/net/i40e/i40e_ethdev_vf.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/i40e/i40e_ethdev_vf.c b/drivers/net/i40e/i40e_ethdev_vf.c
index 625981048a..a753a402c3 100644
--- a/drivers/net/i40e/i40e_ethdev_vf.c
+++ b/drivers/net/i40e/i40e_ethdev_vf.c
@@ -1879,7 +1879,7 @@ i40evf_rxq_init(struct rte_eth_dev *dev, struct i40e_rx_queue *rxq)
 					RTE_PKTMBUF_HEADROOM);
 	rxq->hs_mode = i40e_header_split_none;
 	rxq->rx_hdr_len = 0;
-	rxq->rx_buf_len = RTE_ALIGN(buf_size, (1 << I40E_RXQ_CTX_DBUFF_SHIFT));
+	rxq->rx_buf_len = RTE_ALIGN_FLOOR(buf_size, (1 << I40E_RXQ_CTX_DBUFF_SHIFT));
 	len = rxq->rx_buf_len * I40E_MAX_CHAINED_RX_BUFFERS;
 	rxq->max_pkt_len = RTE_MIN(len,
 		dev_data->dev_conf.rxmode.max_rx_pkt_len);
-- 
2.33.0