diff mbox series

[net,v3,5/9] net: axienet: limit minimum TX ring size

Message ID 20220118214132.357349-6-robert.hancock@calian.com (mailing list archive)
State Accepted
Delegated to: Netdev Maintainers
Headers show
Series Xilinx axienet fixes | expand

Checks

Context Check Description
netdev/tree_selection success Clearly marked for net
netdev/fixes_present success Fixes tag present in non-next series
netdev/subject_prefix success Link
netdev/cover_letter success Series has a cover letter
netdev/patch_count success Link
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 2 this patch: 2
netdev/cc_maintainers fail 1 blamed authors not CCed: hancock@sedsystems.ca; 1 maintainers not CCed: hancock@sedsystems.ca
netdev/build_clang success Errors and warnings before: 0 this patch: 0
netdev/module_param success Was 0 now: 0
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/verify_fixes success Fixes tag looks correct
netdev/build_allmodconfig_warn success Errors and warnings before: 2 this patch: 2
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 16 lines checked
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Robert Hancock Jan. 18, 2022, 9:41 p.m. UTC 
The driver will not work properly if the TX ring size is set to below
MAX_SKB_FRAGS + 1 since it needs to hold at least one full maximally
fragmented packet in the TX ring. Limit setting the ring size to below
this value.

Fixes: 8b09ca823ffb4 ("net: axienet: Make RX/TX ring sizes configurable")
Signed-off-by: Robert Hancock <robert.hancock@calian.com>
---
 drivers/net/ethernet/xilinx/xilinx_axienet_main.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/drivers/net/ethernet/xilinx/xilinx_axienet_main.c b/drivers/net/ethernet/xilinx/xilinx_axienet_main.c
index fb486a457c76..3f92001bacaf 100644
--- a/drivers/net/ethernet/xilinx/xilinx_axienet_main.c
+++ b/drivers/net/ethernet/xilinx/xilinx_axienet_main.c
@@ -43,6 +43,7 @@ 
 /* Descriptors defines for Tx and Rx DMA */
 #define TX_BD_NUM_DEFAULT		64
 #define RX_BD_NUM_DEFAULT		1024
+#define TX_BD_NUM_MIN			(MAX_SKB_FRAGS + 1)
 #define TX_BD_NUM_MAX			4096
 #define RX_BD_NUM_MAX			4096
 
@@ -1370,7 +1371,8 @@  axienet_ethtools_set_ringparam(struct net_device *ndev,
 	if (ering->rx_pending > RX_BD_NUM_MAX ||
 	    ering->rx_mini_pending ||
 	    ering->rx_jumbo_pending ||
-	    ering->rx_pending > TX_BD_NUM_MAX)
+	    ering->tx_pending < TX_BD_NUM_MIN ||
+	    ering->tx_pending > TX_BD_NUM_MAX)
 		return -EINVAL;
 
 	if (netif_running(ndev))