The patch below does not apply to the 4.14-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@xxxxxxxxxxxxxxx>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From f6f13c125e05603f68f5bf31f045b95e6d493598 Mon Sep 17 00:00:00 2001
From: Haiyang Zhang <haiyangz@xxxxxxxxxxxxx>
Date: Fri, 21 Feb 2020 08:32:18 -0800
Subject: [PATCH] hv_netvsc: Fix unwanted wakeup in netvsc_attach()
When netvsc_attach() is called by operations like changing MTU, etc.,
an extra wakeup may happen while netvsc_attach() calling
rndis_filter_device_add() which sends rndis messages when queue is
stopped in netvsc_detach(). The completion message will wake up queue 0.
We can reproduce the issue by changing MTU etc., then the wake_queue
counter from "ethtool -S" will increase beyond stop_queue counter:
stop_queue: 0
wake_queue: 1
The issue causes queue wake up, and counter increment, no other ill
effects in current code. So we didn't see any network problem for now.
To fix this, initialize tx_disable to true, and set it to false when
the NIC is ready to be attached or registered.
Fixes: 7b2ee50c0cd5 ("hv_netvsc: common detach logic")
Signed-off-by: Haiyang Zhang <haiyangz@xxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
diff --git a/drivers/net/hyperv/netvsc.c b/drivers/net/hyperv/netvsc.c
index ae3f3084c2ed..1b320bcf150a 100644
--- a/drivers/net/hyperv/netvsc.c
+++ b/drivers/net/hyperv/netvsc.c
@@ -99,7 +99,7 @@ static struct netvsc_device *alloc_net_device(void)
init_waitqueue_head(&net_device->wait_drain);
net_device->destroy = false;
- net_device->tx_disable = false;
+ net_device->tx_disable = true;
net_device->max_pkt = RNDIS_MAX_PKT_DEFAULT;
net_device->pkt_align = RNDIS_PKT_ALIGN_DEFAULT;
diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c
index 65e12cb07f45..2c0a24c606fc 100644
--- a/drivers/net/hyperv/netvsc_drv.c
+++ b/drivers/net/hyperv/netvsc_drv.c
@@ -1068,6 +1068,7 @@ static int netvsc_attach(struct net_device *ndev,
}
/* In any case device is now ready */
+ nvdev->tx_disable = false;
netif_device_attach(ndev);
/* Note: enable and attach happen when sub-channels setup */
@@ -2476,6 +2477,8 @@ static int netvsc_probe(struct hv_device *dev,
else
net->max_mtu = ETH_DATA_LEN;
+ nvdev->tx_disable = false;
+
ret = register_netdevice(net);
if (ret != 0) {
pr_err("Unable to register netdev.\n");
