This is a note to let you know that I've just added the patch titled
hv_netvsc: do not use VF device if link is down
to the 5.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
hv_netvsc-do-not-use-vf-device-if-link-is-down.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From foo@baz Mon 10 Aug 2020 02:07:44 PM CEST
From: Stephen Hemminger <stephen@xxxxxxxxxxxxxxxxxx>
Date: Tue, 4 Aug 2020 09:54:15 -0700
Subject: hv_netvsc: do not use VF device if link is down
From: Stephen Hemminger <stephen@xxxxxxxxxxxxxxxxxx>
[ Upstream commit 7c9864bbccc23e1812ac82966555d68c13ea4006 ]
If the accelerated networking SRIOV VF device has lost carrier
use the synthetic network device which is available as backup
path. This is a rare case since if VF link goes down, normally
the VMBus device will also loose external connectivity as well.
But if the communication is between two VM's on the same host
the VMBus device will still work.
Reported-by: "Shah, Ashish N" <ashish.n.shah@xxxxxxxxx>
Fixes: 0c195567a8f6 ("netvsc: transparent VF management")
Signed-off-by: Stephen Hemminger <stephen@xxxxxxxxxxxxxxxxxx>
Reviewed-by: Haiyang Zhang <haiyangz@xxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/hyperv/netvsc_drv.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)
--- a/drivers/net/hyperv/netvsc_drv.c
+++ b/drivers/net/hyperv/netvsc_drv.c
@@ -531,12 +531,13 @@ static int netvsc_start_xmit(struct sk_b
u32 hash;
struct hv_page_buffer pb[MAX_PAGE_BUFFER_COUNT];
- /* if VF is present and up then redirect packets
- * already called with rcu_read_lock_bh
+ /* If VF is present and up then redirect packets to it.
+ * Skip the VF if it is marked down or has no carrier.
+ * If netpoll is in uses, then VF can not be used either.
*/
vf_netdev = rcu_dereference_bh(net_device_ctx->vf_netdev);
if (vf_netdev && netif_running(vf_netdev) &&
- !netpoll_tx_running(net))
+ netif_carrier_ok(vf_netdev) && !netpoll_tx_running(net))
return netvsc_vf_xmit(net, vf_netdev, skb);
/* We will atmost need two pages to describe the rndis
Patches currently in stable-queue which might be from stephen@xxxxxxxxxxxxxxxxxx are
queue-5.4/hv_netvsc-do-not-use-vf-device-if-link-is-down.patch
