[PATCH AUTOSEL 5.1 38/70] net: aquantia: fix LRO with FCS error

From: Sasha Levin
Date: Sat Jun 08 2019 - 07:57:37 EST


From: Dmitry Bogdanov <dmitry.bogdanov@xxxxxxxxxxxx>

[ Upstream commit eaeb3b7494ba9159323814a8ce8af06a9277d99b ]

Driver stops producing skbs on ring if a packet with FCS error
was coalesced into LRO session. Ring gets hang forever.

Thats a logical error in driver processing descriptors:
When rx_stat indicates MAC Error, next pointer and eop flags
are not filled. This confuses driver so it waits for descriptor 0
to be filled by HW.

Solution is fill next pointer and eop flag even for packets with FCS error.

Fixes: bab6de8fd180b ("net: ethernet: aquantia: Atlantic A0 and B0 specific functions.")
Signed-off-by: Igor Russkikh <igor.russkikh@xxxxxxxxxxxx>
Signed-off-by: Dmitry Bogdanov <dmitry.bogdanov@xxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
.../aquantia/atlantic/hw_atl/hw_atl_b0.c | 61 ++++++++++---------
1 file changed, 32 insertions(+), 29 deletions(-)

diff --git a/drivers/net/ethernet/aquantia/atlantic/hw_atl/hw_atl_b0.c b/drivers/net/ethernet/aquantia/atlantic/hw_atl/hw_atl_b0.c
index b31dba1b1a55..ec302fdfec63 100644
--- a/drivers/net/ethernet/aquantia/atlantic/hw_atl/hw_atl_b0.c
+++ b/drivers/net/ethernet/aquantia/atlantic/hw_atl/hw_atl_b0.c
@@ -702,38 +702,41 @@ static int hw_atl_b0_hw_ring_rx_receive(struct aq_hw_s *self,
if ((rx_stat & BIT(0)) || rxd_wb->type & 0x1000U) {
/* MAC error or DMA error */
buff->is_error = 1U;
- } else {
- if (self->aq_nic_cfg->is_rss) {
- /* last 4 byte */
- u16 rss_type = rxd_wb->type & 0xFU;
-
- if (rss_type && rss_type < 0x8U) {
- buff->is_hash_l4 = (rss_type == 0x4 ||
- rss_type == 0x5);
- buff->rss_hash = rxd_wb->rss_hash;
- }
+ }
+ if (self->aq_nic_cfg->is_rss) {
+ /* last 4 byte */
+ u16 rss_type = rxd_wb->type & 0xFU;
+
+ if (rss_type && rss_type < 0x8U) {
+ buff->is_hash_l4 = (rss_type == 0x4 ||
+ rss_type == 0x5);
+ buff->rss_hash = rxd_wb->rss_hash;
}
+ }

- if (HW_ATL_B0_RXD_WB_STAT2_EOP & rxd_wb->status) {
- buff->len = rxd_wb->pkt_len %
- AQ_CFG_RX_FRAME_MAX;
- buff->len = buff->len ?
- buff->len : AQ_CFG_RX_FRAME_MAX;
- buff->next = 0U;
- buff->is_eop = 1U;
+ if (HW_ATL_B0_RXD_WB_STAT2_EOP & rxd_wb->status) {
+ buff->len = rxd_wb->pkt_len %
+ AQ_CFG_RX_FRAME_MAX;
+ buff->len = buff->len ?
+ buff->len : AQ_CFG_RX_FRAME_MAX;
+ buff->next = 0U;
+ buff->is_eop = 1U;
+ } else {
+ buff->len =
+ rxd_wb->pkt_len > AQ_CFG_RX_FRAME_MAX ?
+ AQ_CFG_RX_FRAME_MAX : rxd_wb->pkt_len;
+
+ if (HW_ATL_B0_RXD_WB_STAT2_RSCCNT &
+ rxd_wb->status) {
+ /* LRO */
+ buff->next = rxd_wb->next_desc_ptr;
+ ++ring->stats.rx.lro_packets;
} else {
- if (HW_ATL_B0_RXD_WB_STAT2_RSCCNT &
- rxd_wb->status) {
- /* LRO */
- buff->next = rxd_wb->next_desc_ptr;
- ++ring->stats.rx.lro_packets;
- } else {
- /* jumbo */
- buff->next =
- aq_ring_next_dx(ring,
- ring->hw_head);
- ++ring->stats.rx.jumbo_packets;
- }
+ /* jumbo */
+ buff->next =
+ aq_ring_next_dx(ring,
+ ring->hw_head);
+ ++ring->stats.rx.jumbo_packets;
}
}
}
--
2.20.1