[net v1 PATCH] hsr: fix incorrect warning

[Murali Karicheri <m-karicheri2@ti.com>]

When HSR interface is setup using ip link command, an annoying warning
appears with the trace as below:-

[  203.019828] hsr_get_node: Non-HSR frame
[  203.019833] Modules linked in:
[  203.019848] CPU: 0 PID: 158 Comm: sd-resolve Tainted: G        W       4.12.0-rc3-00052-g9fa6bf70 #2
[  203.019853] Hardware name: Generic DRA74X (Flattened Device Tree)
[  203.019869] [<c0110280>] (unwind_backtrace) from [<c010c2f4>] (show_stack+0x10/0x14)
[  203.019880] [<c010c2f4>] (show_stack) from [<c04b9f64>] (dump_stack+0xac/0xe0)
[  203.019894] [<c04b9f64>] (dump_stack) from [<c01374e8>] (__warn+0xd8/0x104)
[  203.019907] [<c01374e8>] (__warn) from [<c0137548>] (warn_slowpath_fmt+0x34/0x44)
root@am57xx-evm:~# [  203.019921] [<c0137548>] (warn_slowpath_fmt) from [<c081126c>] (hsr_get_node+0x148/0x170)
[  203.019932] [<c081126c>] (hsr_get_node) from [<c0814240>] (hsr_forward_skb+0x110/0x7c0)
[  203.019942] [<c0814240>] (hsr_forward_skb) from [<c0811d64>] (hsr_dev_xmit+0x2c/0x34)
[  203.019954] [<c0811d64>] (hsr_dev_xmit) from [<c06c0828>] (dev_hard_start_xmit+0xc4/0x3bc)
[  203.019963] [<c06c0828>] (dev_hard_start_xmit) from [<c06c13d8>] (__dev_queue_xmit+0x7c4/0x98c)
[  203.019974] [<c06c13d8>] (__dev_queue_xmit) from [<c0782f54>] (ip6_finish_output2+0x330/0xc1c)
[  203.019983] [<c0782f54>] (ip6_finish_output2) from [<c0788f0c>] (ip6_output+0x58/0x454)
[  203.019994] [<c0788f0c>] (ip6_output) from [<c07b16cc>] (mld_sendpack+0x420/0x744)

As this is an expected path to hsr_get_node() with frame coming from
the master interface, add a check to ensure packet is not from the
master port and then warn.

Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
---
 v1 - sending as a separate patch to apply to net as per comment from David
Miller.
 net/hsr/hsr_forward.c  | 3 +--
 net/hsr/hsr_framereg.c | 9 +++++++--
 net/hsr/hsr_framereg.h | 2 +-
 3 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/net/hsr/hsr_forward.c b/net/hsr/hsr_forward.c
index 4ebe2aa..04b5450 100644
--- a/net/hsr/hsr_forward.c
+++ b/net/hsr/hsr_forward.c
@@ -324,8 +324,7 @@ static int hsr_fill_frame_info(struct hsr_frame_info *frame,
 	unsigned long irqflags;
 
 	frame->is_supervision = is_supervision_frame(port->hsr, skb);
-	frame->node_src = hsr_get_node(&port->hsr->node_db, skb,
-				       frame->is_supervision);
+	frame->node_src = hsr_get_node(port, skb, frame->is_supervision);
 	if (frame->node_src == NULL)
 		return -1; /* Unknown node and !is_supervision, or no mem */
 
diff --git a/net/hsr/hsr_framereg.c b/net/hsr/hsr_framereg.c
index 7ea9258..284a9b8 100644
--- a/net/hsr/hsr_framereg.c
+++ b/net/hsr/hsr_framereg.c
@@ -158,9 +158,10 @@ struct hsr_node *hsr_add_node(struct list_head *node_db, unsigned char addr[],
 
 /* Get the hsr_node from which 'skb' was sent.
  */
-struct hsr_node *hsr_get_node(struct list_head *node_db, struct sk_buff *skb,
+struct hsr_node *hsr_get_node(struct hsr_port *port, struct sk_buff *skb,
 			      bool is_sup)
 {
+	struct list_head *node_db = &port->hsr->node_db;
 	struct hsr_node *node;
 	struct ethhdr *ethhdr;
 	u16 seq_out;
@@ -186,7 +187,11 @@ struct hsr_node *hsr_get_node(struct list_head *node_db, struct sk_buff *skb,
 		 */
 		seq_out = hsr_get_skb_sequence_nr(skb) - 1;
 	} else {
-		WARN_ONCE(1, "%s: Non-HSR frame\n", __func__);
+		/* this is called also for frames from master port and
+		 * so warn only for non master ports
+		 */
+		if (port->type != HSR_PT_MASTER)
+			WARN_ONCE(1, "%s: Non-HSR frame\n", __func__);
 		seq_out = HSR_SEQNR_START;
 	}
 
diff --git a/net/hsr/hsr_framereg.h b/net/hsr/hsr_framereg.h
index 438b40f..4e04f0e 100644
--- a/net/hsr/hsr_framereg.h
+++ b/net/hsr/hsr_framereg.h
@@ -18,7 +18,7 @@
 
 struct hsr_node *hsr_add_node(struct list_head *node_db, unsigned char addr[],
 			      u16 seq_out);
-struct hsr_node *hsr_get_node(struct list_head *node_db, struct sk_buff *skb,
+struct hsr_node *hsr_get_node(struct hsr_port *port, struct sk_buff *skb,
 			      bool is_sup);
 void hsr_handle_sup_frame(struct sk_buff *skb, struct hsr_node *node_curr,
 			  struct hsr_port *port);
-- 
1.9.1