From: Stephen Hemminger <stephen@networkplumber.org>
Date: Fri, 2 Mar 2018 13:49:04 -0800
Patch-mainline: v4.16-rc5
Subject: hv_netvsc: cancel subchannel setup before halting device
Git-commit: a7483ec0267c69b34e818738da60b392623da94b
References: fate#323887

Block setup of multiple channels earlier in the teardown
process. This avoids possible races between halt and subchannel
initialization.

Suggested-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Olaf Hering <ohering@suse.de>
---
 drivers/net/hyperv/rndis_filter.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/net/hyperv/rndis_filter.c b/drivers/net/hyperv/rndis_filter.c
--- a/drivers/net/hyperv/rndis_filter.c
+++ b/drivers/net/hyperv/rndis_filter.c
@@ -1340,6 +1340,9 @@ void rndis_filter_device_remove(struct hv_device *dev,
 {
 	struct rndis_device *rndis_dev = net_dev->extension;
 
+	/* Don't try and setup sub channels if about to halt */
+	cancel_work_sync(&net_dev->subchan_work);
+
 	/* Halt and release the rndis device */
 	rndis_filter_halt_device(rndis_dev);