Re: [PATCH] net: hsr: add support for EntryForgetTime

In IEC 62439-3 EntryForgetTime is defined with a value of 400 ms. When a
node does not send any frame within this time, the sequence number check
for can be ignored. This solves communication issues with Cisco IE 2000
in Redbox mode.

Fixes: f421436a591d ("net/hsr: Add support for the High-availability Seamless Redundancy protocol (HSRv0)")
Signed-off-by: Marco Wenzel <redacted>
---
 net/hsr/hsr_framereg.c | 9 +++++++--
 net/hsr/hsr_framereg.h | 1 +
 net/hsr/hsr_main.h     | 1 +
 3 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/net/hsr/hsr_framereg.c b/net/hsr/hsr_framereg.c
index 5c97de459905..805f974923b9 100644
--- a/net/hsr/hsr_framereg.c
+++ b/net/hsr/hsr_framereg.c

@@ -164,8 +164,10 @@ static struct hsr_node *hsr_add_node(struct hsr_priv *hsr,
         * as initialization. (0 could trigger an spurious ring error warning).
         */
        now = jiffies;
-       for (i = 0; i < HSR_PT_PORTS; i++)
+       for (i = 0; i < HSR_PT_PORTS; i++) {
                new_node->time_in[i] = now;
+               new_node->time_out[i] = now;
+       }
        for (i = 0; i < HSR_PT_PORTS; i++)
                new_node->seq_out[i] = seq_out;

@@ -411,9 +413,12 @@ void hsr_register_frame_in(struct hsr_node *node, struct hsr_port *port,
 int hsr_register_frame_out(struct hsr_port *port, struct hsr_node *node,
                           u16 sequence_nr)
 {
-       if (seq_nr_before_or_eq(sequence_nr, node->seq_out[port->type]))
+       if (seq_nr_before_or_eq(sequence_nr, node->seq_out[port->type]) &&
+           time_is_after_jiffies(node->time_out[port->type] +
+           msecs_to_jiffies(HSR_ENTRY_FORGET_TIME)))
                return 1;

+       node->time_out[port->type] = jiffies;
        node->seq_out[port->type] = sequence_nr;
        return 0;
 }

diff --git a/net/hsr/hsr_framereg.h b/net/hsr/hsr_framereg.h
index 86b43f539f2c..d9628e7a5f05 100644
--- a/net/hsr/hsr_framereg.h
+++ b/net/hsr/hsr_framereg.h

@@ -75,6 +75,7 @@ struct hsr_node {
        enum hsr_port_type      addr_B_port;
        unsigned long           time_in[HSR_PT_PORTS];
        bool                    time_in_stale[HSR_PT_PORTS];
+       unsigned long           time_out[HSR_PT_PORTS];
        /* if the node is a SAN */
        bool                    san_a;
        bool                    san_b;

diff --git a/net/hsr/hsr_main.h b/net/hsr/hsr_main.h
index 7dc92ce5a134..f79ca55d6986 100644
--- a/net/hsr/hsr_main.h
+++ b/net/hsr/hsr_main.h

@@ -21,6 +21,7 @@
 #define HSR_LIFE_CHECK_INTERVAL                 2000 /* ms */
 #define HSR_NODE_FORGET_TIME           60000 /* ms */
 #define HSR_ANNOUNCE_INTERVAL            100 /* ms */
+#define HSR_ENTRY_FORGET_TIME            400 /* ms */

 /* By how much may slave1 and slave2 timestamps of latest received frame from
  * each node differ before we notify of communication problem?
--

2.30.0