6.12-stable review patch. If anyone has any objections, please let me know.
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From: Paul Barker paul.barker.ct@bp.renesas.com
[ Upstream commit e7e441a4100e4bc90b52f80494a28a9667993975 ]
When tx_max_frame_size was added to struct ravb_hw_info, no value was set in ravb_rzv2m_hw_info so the default value of zero was used.
The maximum MTU is set by subtracting from tx_max_frame_size to allow space for headers and frame checksums. As ndev->max_mtu is unsigned, this subtraction wraps around leading to a ridiculously large positive value that is obviously incorrect.
Before tx_max_frame_size was introduced, the maximum MTU was based on rx_max_frame_size. So, we can restore the correct maximum MTU by copying the rx_max_frame_size value into tx_max_frame_size for RZ/V2M.
Fixes: 1d63864299ca ("net: ravb: Fix maximum TX frame size for GbEth devices") Signed-off-by: Paul Barker paul.barker.ct@bp.renesas.com Reviewed-by: Niklas Söderlund niklas.soderlund+renesas@ragnatech.se Reviewed-by: Simon Horman horms@kernel.org Reviewed-by: Sergey Shtylyov s.shtylyov@omp.ru Link: https://patch.msgid.link/20250109113706.1409149-1-paul.barker.ct@bp.renesas.... Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/renesas/ravb_main.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c index 907af4651c553..6f6b0566c65bc 100644 --- a/drivers/net/ethernet/renesas/ravb_main.c +++ b/drivers/net/ethernet/renesas/ravb_main.c @@ -2756,6 +2756,7 @@ static const struct ravb_hw_info ravb_rzv2m_hw_info = { .net_features = NETIF_F_RXCSUM, .stats_len = ARRAY_SIZE(ravb_gstrings_stats), .tccr_mask = TCCR_TSRQ0 | TCCR_TSRQ1 | TCCR_TSRQ2 | TCCR_TSRQ3, + .tx_max_frame_size = SZ_2K, .rx_max_frame_size = SZ_2K, .rx_buffer_size = SZ_2K + SKB_DATA_ALIGN(sizeof(struct skb_shared_info)),