Blob Blame History Raw
From: Eric Dumazet <edumazet@google.com>
Date: Fri, 21 Sep 2018 15:27:49 -0700
Subject: bnx2x: remove ndo_poll_controller
Patch-mainline: v4.19-rc6
Git-commit: d8ea6a91ad70ae0881d76446df27d3f58fd478c3
References: bsc#1104402 FATE#325899

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.

bnx2x 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: Ariel Elior <ariel.elior@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: David Chang <dchang@suse.com>
---
 drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c |   16 ----------------
 1 file changed, 16 deletions(-)

--- a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c
+++ b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c
@@ -12894,19 +12894,6 @@ static int bnx2x_ioctl(struct net_device
 	}
 }
 
-#ifdef CONFIG_NET_POLL_CONTROLLER
-static void poll_bnx2x(struct net_device *dev)
-{
-	struct bnx2x *bp = netdev_priv(dev);
-	int i;
-
-	for_each_eth_queue(bp, i) {
-		struct bnx2x_fastpath *fp = &bp->fp[i];
-		napi_schedule(&bnx2x_fp(bp, fp->index, napi));
-	}
-}
-#endif
-
 static int bnx2x_validate_addr(struct net_device *dev)
 {
 	struct bnx2x *bp = netdev_priv(dev);
@@ -13113,9 +13100,6 @@ static const struct net_device_ops bnx2x
 	.ndo_tx_timeout		= bnx2x_tx_timeout,
 	.ndo_vlan_rx_add_vid	= bnx2x_vlan_rx_add_vid,
 	.ndo_vlan_rx_kill_vid	= bnx2x_vlan_rx_kill_vid,
-#ifdef CONFIG_NET_POLL_CONTROLLER
-	.ndo_poll_controller	= poll_bnx2x,
-#endif
 	.ndo_setup_tc		= __bnx2x_setup_tc,
 #ifdef CONFIG_BNX2X_SRIOV
 	.ndo_set_vf_mac		= bnx2x_set_vf_mac,