From: Eric Dumazet <edumazet@google.com>
Date: Thu, 27 Sep 2018 09:31:57 -0700
Subject: qlogic: netxen: remove ndo_poll_controller
Patch-mainline: v4.19-rc7
Git-commit: 3548fcf7d877c682c9a5a413c51929739192156d
References: bsc#1104399 FATE#325896
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.
netxen 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: Manish Chopra <manish.chopra@cavium.com>
Cc: Rahul Verma <rahul.verma@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: David Chang <dchang@suse.com>
---
drivers/net/ethernet/qlogic/netxen/netxen_nic_main.c | 23 -------------------
1 file changed, 23 deletions(-)
--- a/drivers/net/ethernet/qlogic/netxen/netxen_nic_main.c
+++ b/drivers/net/ethernet/qlogic/netxen/netxen_nic_main.c
@@ -72,9 +72,6 @@ static void netxen_schedule_work(struct
work_func_t func, int delay);
static void netxen_cancel_fw_work(struct netxen_adapter *adapter);
static int netxen_nic_poll(struct napi_struct *napi, int budget);
-#ifdef CONFIG_NET_POLL_CONTROLLER
-static void netxen_nic_poll_controller(struct net_device *netdev);
-#endif
static void netxen_create_sysfs_entries(struct netxen_adapter *adapter);
static void netxen_remove_sysfs_entries(struct netxen_adapter *adapter);
@@ -581,9 +578,6 @@ static const struct net_device_ops netxe
.ndo_tx_timeout = netxen_tx_timeout,
.ndo_fix_features = netxen_fix_features,
.ndo_set_features = netxen_set_features,
-#ifdef CONFIG_NET_POLL_CONTROLLER
- .ndo_poll_controller = netxen_nic_poll_controller,
-#endif
};
static inline bool netxen_function_zero(struct pci_dev *pdev)
@@ -2402,23 +2396,6 @@ static int netxen_nic_poll(struct napi_s
return work_done;
}
-#ifdef CONFIG_NET_POLL_CONTROLLER
-static void netxen_nic_poll_controller(struct net_device *netdev)
-{
- int ring;
- struct nx_host_sds_ring *sds_ring;
- struct netxen_adapter *adapter = netdev_priv(netdev);
- struct netxen_recv_context *recv_ctx = &adapter->recv_ctx;
-
- disable_irq(adapter->irq);
- for (ring = 0; ring < adapter->max_sds_rings; ring++) {
- sds_ring = &recv_ctx->sds_rings[ring];
- netxen_intr(adapter->irq, sds_ring);
- }
- enable_irq(adapter->irq);
-}
-#endif
-
static int
nx_incr_dev_ref_cnt(struct netxen_adapter *adapter)
{