From: Eric Dumazet <edumazet@google.com>
Date: Thu, 27 Sep 2018 09:31:56 -0700
Subject: qlcnic: remove ndo_poll_controller
Patch-mainline: v4.19-rc7
Git-commit: 81b059b2187d77b957bf85318dbd4f36d60555e3
References: bsc#1104396 FATE#325894
As diagnosed by Song Liu, ndo_poll_controller() can
be very dangerous on loaded hosts, since the cpu
calling ndo_poll_controller() might steal all NAPI
contexts (for all RX/TX queues of the NIC). This capture
can last for unlimited amount of time, since one
cpu is generally not able to drain all the queues under load.
qlcnic uses NAPI for TX completions, so we better let core
networking stack call the napi->poll() to avoid the capture.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Harish Patil <harish.patil@cavium.com>
Cc: Manish Chopra <manish.chopra@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: David Chang <dchang@suse.com>
---
drivers/net/ethernet/qlogic/qlcnic/qlcnic_main.c | 45 -----------------------
1 file changed, 45 deletions(-)
--- a/drivers/net/ethernet/qlogic/qlcnic/qlcnic_main.c
+++ b/drivers/net/ethernet/qlogic/qlcnic/qlcnic_main.c
@@ -59,9 +59,6 @@ static int qlcnic_close(struct net_devic
static void qlcnic_tx_timeout(struct net_device *netdev);
static void qlcnic_attach_work(struct work_struct *work);
static void qlcnic_fwinit_work(struct work_struct *work);
-#ifdef CONFIG_NET_POLL_CONTROLLER
-static void qlcnic_poll_controller(struct net_device *netdev);
-#endif
static void qlcnic_idc_debug_info(struct qlcnic_adapter *adapter, u8 encoding);
static int qlcnic_can_start_firmware(struct qlcnic_adapter *adapter);
@@ -545,9 +542,6 @@ static const struct net_device_ops qlcni
.ndo_udp_tunnel_add = qlcnic_add_vxlan_port,
.ndo_udp_tunnel_del = qlcnic_del_vxlan_port,
.ndo_features_check = qlcnic_features_check,
-#ifdef CONFIG_NET_POLL_CONTROLLER
- .ndo_poll_controller = qlcnic_poll_controller,
-#endif
#ifdef CONFIG_QLCNIC_SRIOV
.ndo_set_vf_mac = qlcnic_sriov_set_vf_mac,
.ndo_set_vf_rate = qlcnic_sriov_set_vf_tx_rate,
@@ -3197,45 +3191,6 @@ static irqreturn_t qlcnic_msix_tx_intr(i
return IRQ_HANDLED;
}
-#ifdef CONFIG_NET_POLL_CONTROLLER
-static void qlcnic_poll_controller(struct net_device *netdev)
-{
- struct qlcnic_adapter *adapter = netdev_priv(netdev);
- struct qlcnic_host_sds_ring *sds_ring;
- struct qlcnic_recv_context *recv_ctx;
- struct qlcnic_host_tx_ring *tx_ring;
- int ring;
-
- if (!test_bit(__QLCNIC_DEV_UP, &adapter->state))
- return;
-
- recv_ctx = adapter->recv_ctx;
-
- for (ring = 0; ring < adapter->drv_sds_rings; ring++) {
- sds_ring = &recv_ctx->sds_rings[ring];
- qlcnic_disable_sds_intr(adapter, sds_ring);
- napi_schedule(&sds_ring->napi);
- }
-
- if (adapter->flags & QLCNIC_MSIX_ENABLED) {
- /* Only Multi-Tx queue capable devices need to
- * schedule NAPI for TX rings
- */
- if ((qlcnic_83xx_check(adapter) &&
- (adapter->flags & QLCNIC_TX_INTR_SHARED)) ||
- (qlcnic_82xx_check(adapter) &&
- !qlcnic_check_multi_tx(adapter)))
- return;
-
- for (ring = 0; ring < adapter->drv_tx_rings; ring++) {
- tx_ring = &adapter->tx_ring[ring];
- qlcnic_disable_tx_intr(adapter, tx_ring);
- napi_schedule(&tx_ring->napi);
- }
- }
-}
-#endif
-
static void
qlcnic_idc_debug_info(struct qlcnic_adapter *adapter, u8 encoding)
{