diff options
| -rw-r--r-- | drivers/net/ethernet/sfc/efx.c | 12 | ||||
| -rw-r--r-- | drivers/net/ethernet/sfc/net_driver.h | 3 |
2 files changed, 14 insertions, 1 deletions
diff --git a/drivers/net/ethernet/sfc/efx.c b/drivers/net/ethernet/sfc/efx.c index f3826ae28bac..3cf3557106c2 100644 --- a/drivers/net/ethernet/sfc/efx.c +++ b/drivers/net/ethernet/sfc/efx.c @@ -2263,8 +2263,18 @@ static int efx_change_mtu(struct net_device *net_dev, int new_mtu) rc = efx_check_disabled(efx); if (rc) return rc; - if (new_mtu > EFX_MAX_MTU) + if (new_mtu > EFX_MAX_MTU) { + netif_err(efx, drv, efx->net_dev, + "Requested MTU of %d too big (max: %d)\n", + new_mtu, EFX_MAX_MTU); return -EINVAL; + } + if (new_mtu < EFX_MIN_MTU) { + netif_err(efx, drv, efx->net_dev, + "Requested MTU of %d too small (min: %d)\n", + new_mtu, EFX_MIN_MTU); + return -EINVAL; + } netif_dbg(efx, drv, efx->net_dev, "changing MTU to %d\n", new_mtu); diff --git a/drivers/net/ethernet/sfc/net_driver.h b/drivers/net/ethernet/sfc/net_driver.h index 0a2504b5dad5..99d8c82124bb 100644 --- a/drivers/net/ethernet/sfc/net_driver.h +++ b/drivers/net/ethernet/sfc/net_driver.h @@ -76,6 +76,9 @@ /* Maximum possible MTU the driver supports */ #define EFX_MAX_MTU (9 * 1024) +/* Minimum MTU, from RFC791 (IP) */ +#define EFX_MIN_MTU 68 + /* Size of an RX scatter buffer. Small enough to pack 2 into a 4K page, * and should be a multiple of the cache line size. */ |