@@ -564,7 +564,7 @@ static netdev_tx_t bnxt_start_xmit(struct sk_buff *skb, struct net_device *dev)
TX_BD_FLAGS_LHINT_512_AND_SMALLER |
TX_BD_FLAGS_COAL_NOW |
TX_BD_FLAGS_PACKET_END |
- (2 << TX_BD_FLAGS_BD_CNT_SHIFT));
+ TX_BD_CNT(2));
if (skb->ip_summed == CHECKSUM_PARTIAL)
tx_push1->tx_bd_hsize_lflags =
@@ -639,7 +639,7 @@ static netdev_tx_t bnxt_start_xmit(struct sk_buff *skb, struct net_device *dev)
dma_unmap_addr_set(tx_buf, mapping, mapping);
flags = (len << TX_BD_LEN_SHIFT) | TX_BD_TYPE_LONG_TX_BD |
- ((last_frag + 2) << TX_BD_FLAGS_BD_CNT_SHIFT);
+ TX_BD_CNT(last_frag + 2);
txbd->tx_bd_haddr = cpu_to_le64(mapping);
txbd->tx_bd_opaque = SET_TX_OPAQUE(bp, txr, prod, 2 + last_frag);
@@ -82,6 +82,8 @@ struct tx_bd {
#define TX_OPAQUE_PROD(bp, opq) ((TX_OPAQUE_IDX(opq) + TX_OPAQUE_BDS(opq)) &\
(bp)->tx_ring_mask)
+#define TX_BD_CNT(n) (((n) << TX_BD_FLAGS_BD_CNT_SHIFT) & TX_BD_FLAGS_BD_CNT)
+
struct tx_bd_ext {
__le32 tx_bd_hsize_lflags;
#define TX_BD_FLAGS_TCP_UDP_CHKSUM (1 << 0)
@@ -48,8 +48,7 @@ struct bnxt_sw_tx_bd *bnxt_xmit_bd(struct bnxt *bp,
tx_buf->page = virt_to_head_page(xdp->data);
txbd = &txr->tx_desc_ring[TX_RING(bp, prod)][TX_IDX(prod)];
- flags = (len << TX_BD_LEN_SHIFT) |
- ((num_frags + 1) << TX_BD_FLAGS_BD_CNT_SHIFT) |
+ flags = (len << TX_BD_LEN_SHIFT) | TX_BD_CNT(num_frags + 1) |
bnxt_lhint_arr[len >> 9];
txbd->tx_bd_len_flags_type = cpu_to_le32(flags);
txbd->tx_bd_opaque = SET_TX_OPAQUE(bp, txr, prod, 1 + num_frags);
The bd_cnt field in the TX BD specifies the total number of BDs for the TX packet. The bd_cnt field has 5 bits and the maximum number supported is 32 with the value 0. CONFIG_MAX_SKB_FRAGS can be modified and the total number of SKB fragments can approach or exceed the maximum supported by the chip. Add a macro to properly mask the bd_cnt field so that the value 32 will be properly masked and set to 0 in the bd_cnd field. Without this patch, the out-of-range bd_cnt value will corrupt the TX BD and may cause TX timeout. The next patch will check for values exceeding 32. Fixes: 3948b05950fd ("net: introduce a config option to tweak MAX_SKB_FRAGS") Reviewed-by: Kalesh AP <kalesh-anakkur.purayil@broadcom.com> Reviewed-by: Somnath Kotur <somnath.kotur@broadcom.com> Reviewed-by: Andy Gospodarek <andrew.gospodarek@broadcom.com> Signed-off-by: Michael Chan <michael.chan@broadcom.com> --- drivers/net/ethernet/broadcom/bnxt/bnxt.c | 4 ++-- drivers/net/ethernet/broadcom/bnxt/bnxt.h | 2 ++ drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c | 3 +-- 3 files changed, 5 insertions(+), 4 deletions(-)