| Message ID | 11291f9b05764307b660049e2290dd10@EXCH-SVR2013.eberle.local (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | AW: HSR/PRP sequence counter issue with Cisco Redbox | expand |
On Mon, Feb 15, 2021 at 6:30 AM Wenzel, Marco <Marco.Wenzel@a-eberle.de> wrote: > > > On Wed, Jan 27, 2021 at 6:32 AM Wenzel, Marco <Marco.Wenzel@a- > > eberle.de> wrote: > > > > > > Hi, > > > > > > we have figured out an issue with the current PRP driver when trying to > > communicate with Cisco IE 2000 industrial Ethernet switches in Redbox > > mode. The Cisco always resets the HSR/PRP sequence counter to "1" at low > > traffic (<= 1 frame in 400 ms). It can be reproduced by a simple ICMP echo > > request with 1 s interval between a Linux box running with PRP and a VDAN > > behind the Cisco Redbox. The Linux box then always receives frames with > > sequence counter "1" and drops them. The behavior is not configurable at > > the Cisco Redbox. > > > > > > I fixed it by ignoring sequence counters with value "1" at the sequence > > counter check in hsr_register_frame_out (): > > > > > > diff --git a/net/hsr/hsr_framereg.c b/net/hsr/hsr_framereg.c index > > > 5c97de459905..630c238e81f0 100644 > > > --- a/net/hsr/hsr_framereg.c > > > +++ b/net/hsr/hsr_framereg.c > > > @@ -411,7 +411,7 @@ 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]) && (sequence_nr != 1)) > > > return 1; > > > > > > node->seq_out[port->type] = sequence_nr; > > > > > > > > > Do you think this could be a solution? Should this patch be officially applied > > in order to avoid other users running into these communication issues? > > > > This isn't the correct way to solve the problem. IEC 62439-3 defines > > EntryForgetTime as "Time after which an entry is removed from the duplicate > > table" with a value of 400ms and states devices should usually be configured > > to keep entries in the table for a much shorter time. hsr_framereg.c needs to > > be reworked to handle this according to the specification. > > Sorry for the delay but I did not have the time to take a closer look at the problem until now. > > My suggestion for the EntryForgetTime feature would be the following: A time_out element will be added to the hsr_node structure, which always stores the current time when entering hsr_register_frame_out(). If the last stored time is older than EntryForgetTime (400 ms) the sequence number check will be ignored. > > diff --git a/net/hsr/hsr_framereg.c b/net/hsr/hsr_framereg.c > index 5c97de459905..a97bffbd2581 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? > > > This approach works fine with the Cisco IE 2000 and I think it implements the correct way to handle sequence numbers as defined in IEC 62439-3. Looks good to me. Can you send an official patch? If so I'll try it out. Even if I can't replicate the Cisco situation I can try it with my setups and make sure it doesn't break anything. Regards, George McCollister > > Regards, > Marco Wenzel > > > > > > > Thanks > > > Marco Wenzel > > > > Regards, > > George McCollister
diff --git a/net/hsr/hsr_framereg.c b/net/hsr/hsr_framereg.c index 5c97de459905..a97bffbd2581 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?