[dpdk-dev] [PATCH] net/iavf: fix rxq buf size alignment

[dpdk-dev] [PATCH] net/iavf: fix rxq buf size alignment

[Qiming Chen]

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: 69dd4c3d0898 ("net/avf: enable queue and device")
Cc: stable@dpdk.org

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

diff --git a/drivers/net/iavf/iavf_rxtx.c b/drivers/net/iavf/iavf_rxtx.c
index 59448eae98..79243cddc0 100644
--- a/drivers/net/iavf/iavf_rxtx.c
+++ b/drivers/net/iavf/iavf_rxtx.c
@@ -619,7 +619,7 @@ iavf_dev_rx_queue_setup(struct rte_eth_dev *dev, uint16_t queue_idx,
 		rxq->crc_len = 0;
 
 	len = rte_pktmbuf_data_room_size(rxq->mp) - RTE_PKTMBUF_HEADROOM;
-	rxq->rx_buf_len = RTE_ALIGN(len, (1 << IAVF_RXQ_CTX_DBUFF_SHIFT));
+	rxq->rx_buf_len = RTE_ALIGN_FLOOR(len, (1 << IAVF_RXQ_CTX_DBUFF_SHIFT));
 
 	/* Allocate the software ring. */
 	len = nb_desc + IAVF_RX_MAX_BURST;
-- 
2.30.1.windows.1

Re: [dpdk-dev] [PATCH] net/iavf: fix rxq buf size alignment

[Zhang, Qi Z]

> -----Original Message-----
> From: dev <dev-bounces@dpdk.org> On Behalf Of Qiming Chen
> Sent: Saturday, September 11, 2021 10:08 AM
> To: dev@dpdk.org
> Cc: Xing, Beilei <beilei.xing@intel.com>; Wu, Jingjing <jingjing.wu@intel.com>;
> Qiming Chen <chenqiming_huawei@163.com>; stable@dpdk.org
> Subject: [dpdk-dev] [PATCH] net/iavf: fix rxq buf size alignment
> 
> 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: 69dd4c3d0898 ("net/avf: enable queue and device")
> Cc: stable@dpdk.org
> 
> Signed-off-by: Qiming Chen <chenqiming_huawei@163.com>

Acked-by: Qi Zhang <qi.z.zhang@intel.com>

Applied to dpdk-next-net-intel.

Thanks
Qi