Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     linux-kernel@vger.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        stable@vger.kernel.org, Wei Hu <weh@microsoft.com>,
        Haiyang Zhang <haiyangz@microsoft.com>,
        Michael Kelley <mikelley@microsoft.com>,
        Sasha Levin <sashal@kernel.org>
Subject: [PATCH 4.20 50/88] hv_netvsc: Fix ethtool change hash key error
Date:   Mon,  4 Mar 2019 09:22:33 +0100
Message-Id: <20190304081632.531946807@linuxfoundation.org>
In-Reply-To: <20190304081630.610632175@linuxfoundation.org>
References: <20190304081630.610632175@linuxfoundation.org>
User-Agent: quilt/0.65
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

4.20-stable review patch.  If anyone has any objections, please let me know.

------------------

[ Upstream commit b4a10c750424e01b5e37372fef0a574ebf7b56c3 ]

Hyper-V hosts require us to disable RSS before changing RSS key,
otherwise the changing request will fail. This patch fixes the
coding error.

Fixes: ff4a44199012 ("netvsc: allow get/set of RSS indirection table")
Reported-by: Wei Hu <weh@microsoft.com>
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
[sl: fix up subject line]
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/net/hyperv/rndis_filter.c | 25 +++++++++++++++++++------
 1 file changed, 19 insertions(+), 6 deletions(-)

diff --git a/drivers/net/hyperv/rndis_filter.c b/drivers/net/hyperv/rndis_filter.c
index 8b537a049c1e5..a4661d396e3cd 100644
--- a/drivers/net/hyperv/rndis_filter.c
+++ b/drivers/net/hyperv/rndis_filter.c
@@ -774,8 +774,8 @@ rndis_filter_set_offload_params(struct net_device *ndev,
 	return ret;
 }
 
-int rndis_filter_set_rss_param(struct rndis_device *rdev,
-			       const u8 *rss_key)
+static int rndis_set_rss_param_msg(struct rndis_device *rdev,
+				   const u8 *rss_key, u16 flag)
 {
 	struct net_device *ndev = rdev->ndev;
 	struct rndis_request *request;
@@ -804,7 +804,7 @@ int rndis_filter_set_rss_param(struct rndis_device *rdev,
 	rssp->hdr.type = NDIS_OBJECT_TYPE_RSS_PARAMETERS;
 	rssp->hdr.rev = NDIS_RECEIVE_SCALE_PARAMETERS_REVISION_2;
 	rssp->hdr.size = sizeof(struct ndis_recv_scale_param);
-	rssp->flag = 0;
+	rssp->flag = flag;
 	rssp->hashinfo = NDIS_HASH_FUNC_TOEPLITZ | NDIS_HASH_IPV4 |
 			 NDIS_HASH_TCP_IPV4 | NDIS_HASH_IPV6 |
 			 NDIS_HASH_TCP_IPV6;
@@ -829,9 +829,12 @@ int rndis_filter_set_rss_param(struct rndis_device *rdev,
 
 	wait_for_completion(&request->wait_event);
 	set_complete = &request->response_msg.msg.set_complete;
-	if (set_complete->status == RNDIS_STATUS_SUCCESS)
-		memcpy(rdev->rss_key, rss_key, NETVSC_HASH_KEYLEN);
-	else {
+	if (set_complete->status == RNDIS_STATUS_SUCCESS) {
+		if (!(flag & NDIS_RSS_PARAM_FLAG_DISABLE_RSS) &&
+		    !(flag & NDIS_RSS_PARAM_FLAG_HASH_KEY_UNCHANGED))
+			memcpy(rdev->rss_key, rss_key, NETVSC_HASH_KEYLEN);
+
+	} else {
 		netdev_err(ndev, "Fail to set RSS parameters:0x%x\n",
 			   set_complete->status);
 		ret = -EINVAL;
@@ -842,6 +845,16 @@ int rndis_filter_set_rss_param(struct rndis_device *rdev,
 	return ret;
 }
 
+int rndis_filter_set_rss_param(struct rndis_device *rdev,
+			       const u8 *rss_key)
+{
+	/* Disable RSS before change */
+	rndis_set_rss_param_msg(rdev, rss_key,
+				NDIS_RSS_PARAM_FLAG_DISABLE_RSS);
+
+	return rndis_set_rss_param_msg(rdev, rss_key, 0);
+}
+
 static int rndis_filter_query_device_link_status(struct rndis_device *dev,
 						 struct netvsc_device *net_device)
 {
-- 
2.19.1