[xenial:linux-azure][PATCH 1/6] hv_netvsc: Fix tx_table init in rndis_set_subchannel()

[Marcelo Henrique Cerri]

From: Haiyang Zhang <haiyangz at microsoft.com>

BugLink: http://bugs.launchpad.net/bugs/1864233

Host can provide send indirection table messages anytime after RSS is
enabled by calling rndis_filter_set_rss_param(). So the host provided
table values may be overwritten by the initialization in
rndis_set_subchannel().

To prevent this problem, move the tx_table initialization before calling
rndis_filter_set_rss_param().

Fixes: a6fb6aa3cfa9 ("hv_netvsc: Set tx_table to equal weight after subchannels open")
Signed-off-by: Haiyang Zhang <haiyangz at microsoft.com>
Signed-off-by: Jakub Kicinski <jakub.kicinski at netronome.com>
(backported from commit c39ea5cba5a2e97fc01b78c85208bf31383b399c)
[marcelo.cerri at canonical.com: Fixed context]
Signed-off-by: Marcelo Henrique Cerri <marcelo.cerri at canonical.com>
---
 drivers/net/hyperv/rndis_filter.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/net/hyperv/rndis_filter.c b/drivers/net/hyperv/rndis_filter.c
index e630c3e1410e..934f9901c50e 100644
--- a/drivers/net/hyperv/rndis_filter.c
+++ b/drivers/net/hyperv/rndis_filter.c
@@ -1107,15 +1107,15 @@ int rndis_set_subchannel(struct net_device *ndev, struct netvsc_device *nvdev)
 	wait_event(nvdev->subchan_open,
 		   atomic_read(&nvdev->open_chn) == nvdev->num_chn);
 
+	for (i = 0; i < VRSS_SEND_TAB_SIZE; i++)
+		ndev_ctx->tx_table[i] = i % nvdev->num_chn;
+
 	/* ignore failues from setting rss parameters, still have channels */
 	rndis_filter_set_rss_param(rdev, netvsc_hash_key);
 
 	netif_set_real_num_tx_queues(ndev, nvdev->num_chn);
 	netif_set_real_num_rx_queues(ndev, nvdev->num_chn);
 
-	for (i = 0; i < VRSS_SEND_TAB_SIZE; i++)
-		ndev_ctx->tx_table[i] = i % nvdev->num_chn;
-
 	return 0;
 }
 
-- 
2.20.1