kernel/drivers/net/ethernet/mscc, branch linux-5.14.y

net: dsa: tag_ocelot: break circular dependency with ocelot switch lib driver

2021-11-17T10:04:38Z

[ Upstream commit deab6b1cd9789bb9bd466d5e76aecb8b336259b4 ] As explained here: https://lore.kernel.org/netdev/20210908220834.d7gmtnwrorhharna@skbuf/ DSA tagging protocol drivers cannot depend on symbols exported by switch drivers, because this creates a circular dependency that breaks module autoloading. The tag_ocelot.c file depends on the ocelot_ptp_rew_op() function exported by the common ocelot switch lib. This function looks at OCELOT_SKB_CB(skb) and computes how to populate the REW_OP field of the DSA tag, for PTP timestamping (the command: one-step/two-step, and the TX timestamp identifier). None of that requires deep insight into the driver, it is quite stateless, as it only depends upon the skb->cb. So let's make it a static inline function and put it in include/linux/dsa/ocelot.h, a file that despite its name is used by the ocelot switch driver for populating the injection header too - since commit 40d3f295b5fe ("net: mscc: ocelot: use common tag parsing code with DSA"). With that function declared as static inline, its body is expanded inside each call site, so the dependency is broken and the DSA tagger can be built without the switch library, upon which the felix driver depends. Fixes: 39e5308b3250 ("net: mscc: ocelot: support PTP Sync one-step timestamping") Signed-off-by: Vladimir Oltean Reviewed-by: Florian Fainelli Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

net: mscc: ocelot: Add of_node_put() before goto

2021-11-17T10:03:28Z

[ Upstream commit d1a7b9e4696584ce05c12567762c18a866837a85 ] Fix following coccicheck warning: ./drivers/net/ethernet/mscc/ocelot_vsc7514.c:946:1-33: WARNING: Function for_each_available_child_of_node should have of_node_put() before goto. Early exits from for_each_available_child_of_node should decrement the node reference counter. Signed-off-by: Wan Jiabing Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

net: mscc: ocelot: cross-check the sequence id from the timestamp FIFO with the skb PTP header

2021-10-20T09:57:59Z

commit ebb4c6a990f786d7e0e4618a0d3766cd660125d8 upstream. The sad reality is that when a PTP frame with a TX timestamping request is transmitted, it isn't guaranteed that it will make it all the way to the wire (due to congestion inside the switch), and that a timestamp will be taken by the hardware and placed in the timestamp FIFO where an IRQ will be raised for it. The implication is that if enough PTP frames are silently dropped by the hardware such that the timestamp ID has rolled over, it is possible to match a timestamp to an old skb. Furthermore, nobody will match on the real skb corresponding to this timestamp, since we stupidly matched on a previous one that was stale in the queue, and stopped there. So PTP timestamping will be broken and there will be no way to recover. It looks like the hardware parses the sequenceID from the PTP header, and also provides that metadata for each timestamp. The driver currently ignores this, but it shouldn't. As an extra resiliency measure, do the following: - check whether the PTP sequenceID also matches between the skb and the timestamp, treat the skb as stale otherwise and free it - if we see a stale skb, don't stop there and try to match an skb one more time, chances are there's one more skb in the queue with the same timestamp ID, otherwise we wouldn't have ever found the stale one (it is by timestamp ID that we matched it). While this does not prevent PTP packet drops, it at least prevents the catastrophic consequences of incorrect timestamp matching. Since we already call ptp_classify_raw in the TX path, save the result in the skb->cb of the clone, and just use that result in the interrupt code path. Fixes: 4e3b0468e6d7 ("net: mscc: PTP Hardware Clock (PHC) support") Signed-off-by: Vladimir Oltean Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman

net: mscc: ocelot: deny TX timestamping of non-PTP packets

2021-10-20T09:57:59Z

commit fba01283d85a09e0e2ef552c6e764b903111d90a upstream. It appears that Ocelot switches cannot timestamp non-PTP frames, I tested this using the isochron program at: https://github.com/vladimiroltean/tsn-scripts with the result that the driver increments the ocelot_port->ts_id counter as expected, puts it in the REW_OP, but the hardware seems to not timestamp these packets at all, since no IRQ is emitted. Therefore check whether we are sending PTP frames, and refuse to populate REW_OP otherwise. Fixes: 4e3b0468e6d7 ("net: mscc: PTP Hardware Clock (PHC) support") Signed-off-by: Vladimir Oltean Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman

net: mscc: ocelot: warn when a PTP IRQ is raised for an unknown skb

2021-10-20T09:57:59Z

commit 9fde506e0c53b8309f69b18b4b8144c544b4b3b1 upstream. When skb_match is NULL, it means we received a PTP IRQ for a timestamp ID that the kernel has no idea about, since there is no skb in the timestamping queue with that timestamp ID. This is a grave error and not something to just "continue" over. So print a big warning in case this happens. Also, move the check above ocelot_get_hwtimestamp(), there is no point in reading the full 64-bit current PTP time if we're not going to do anything with it anyway for this skb. Fixes: 4e3b0468e6d7 ("net: mscc: PTP Hardware Clock (PHC) support") Signed-off-by: Vladimir Oltean Reviewed-by: Florian Fainelli Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman

net: mscc: ocelot: avoid overflowing the PTP timestamp FIFO

2021-10-20T09:57:58Z

commit 52849bcf0029ccc553be304e4f804938a39112e2 upstream. PTP packets with 2-step TX timestamp requests are matched to packets based on the egress port number and a 6-bit timestamp identifier. All PTP timestamps are held in a common FIFO that is 128 entry deep. This patch ensures that back-to-back timestamping requests cannot exceed the hardware FIFO capacity. If that happens, simply send the packets without requesting a TX timestamp to be taken (in the case of felix, since the DSA API has a void return code in ds->ops->port_txtstamp) or drop them (in the case of ocelot). I've moved the ts_id_lock from a per-port basis to a per-switch basis, because we need separate accounting for both numbers of PTP frames in flight. And since we need locking to inc/dec the per-switch counter, that also offers protection for the per-port counter and hence there is no reason to have a per-port counter anymore. Fixes: 4e3b0468e6d7 ("net: mscc: PTP Hardware Clock (PHC) support") Signed-off-by: Vladimir Oltean Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman

net: mscc: ocelot: make use of all 63 PTP timestamp identifiers

2021-10-20T09:57:58Z

commit c57fe0037a4e3863d9b740f8c14df9c51ac31aa1 upstream. At present, there is a problem when user space bombards a port with PTP event frames which have TX timestamping requests (or when a tc-taprio offload is installed on a port, which delays the TX timestamps by a significant amount of time). The driver will happily roll over the 2-bit timestamp ID and this will cause incorrect matches between an skb and the TX timestamp collected from the FIFO. The Ocelot switches have a 6-bit PTP timestamp identifier, and the value 63 is reserved, so that leaves identifiers 0-62 to be used. The timestamp identifiers are selected by the REW_OP packet field, and are actually shared between CPU-injected frames and frames which match a VCAP IS2 rule that modifies the REW_OP. The hardware supports partitioning between the two uses of the REW_OP field through the PTP_ID_LOW and PTP_ID_HIGH registers, and by default reserves the PTP IDs 0-3 for CPU-injected traffic and the rest for VCAP IS2. The driver does not use VCAP IS2 to set REW_OP for 2-step timestamping, and it also writes 0xffffffff to both PTP_ID_HIGH and PTP_ID_LOW in ocelot_init_timestamp() which makes all timestamp identifiers available to CPU injection. Therefore, we can make use of all 63 timestamp identifiers, which should allow more timestampable packets to be in flight on each port. This is only part of the solution, more issues will be addressed in future changes. Fixes: 4e3b0468e6d7 ("net: mscc: PTP Hardware Clock (PHC) support") Signed-off-by: Vladimir Oltean Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman

net: mscc: ocelot: fix VCAP filters remaining active after being deleted

2021-10-13T07:41:56Z

[ Upstream commit 019d9329e7481cfaccbd8ed17b1e04ca76970f13 ] When ocelot_flower.c calls ocelot_vcap_filter_add(), the filter has a given filter->id.cookie. This filter is added to the block->rules list. However, when ocelot_flower.c calls ocelot_vcap_block_find_filter_by_id() which passes the cookie as argument, the filter is never found by filter->id.cookie when searching through the block->rules list. This is unsurprising, since the filter->id.cookie is an unsigned long, but the cookie argument provided to ocelot_vcap_block_find_filter_by_id() is a signed int, and the comparison fails. Fixes: 50c6cc5b9283 ("net: mscc: ocelot: store a namespaced VCAP filter ID") Signed-off-by: Vladimir Oltean Link: https://lore.kernel.org/r/20210930125330.2078625-1-vladimir.oltean@nxp.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

net: mscc: ocelot: fix forwarding from BLOCKING ports remaining enabled

2021-09-30T08:13:01Z

[ Upstream commit acc64f52afac15e9e44d9b5253271346841786e0 ] The blamed commit made the fatally incorrect assumption that ports which aren't in the FORWARDING STP state should not have packets forwarded towards them, and that is all that needs to be done. However, that logic alone permits BLOCKING ports to forward to FORWARDING ports, which of course allows packet storms to occur when there is an L2 loop. The ocelot_get_bridge_fwd_mask should not only ask "what can the bridge do for you", but "what can you do for the bridge". This way, only FORWARDING ports forward to the other FORWARDING ports from the same bridging domain, and we are still compatible with the idea of multiple bridges. Fixes: df291e54ccca ("net: ocelot: support multiple bridges") Suggested-by: Colin Foster Reported-by: Colin Foster Signed-off-by: Vladimir Oltean Signed-off-by: Colin Foster Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

net: mscc: ocelot: allow forwarding from bridge ports to the tag_8021q CPU port

2021-08-18T22:34:52Z

Currently we are unable to ping a bridge on top of a felix switch which uses the ocelot-8021q tagger. The packets are dropped on the ingress of the user port and the 'drop_local' counter increments (the counter which denotes drops due to no valid destinations). Dumping the PGID tables, it becomes clear that the PGID_SRC of the user port is zero, so it has no valid destinations. But looking at the code, the cpu_fwd_mask (the bit mask of DSA tag_8021q ports) is clearly missing from the forwarding mask of ports that are under a bridge. So this has always been broken. Looking at the version history of the patch, in v7 https://patchwork.kernel.org/project/netdevbpf/patch/20210125220333.1004365-12-olteanv@gmail.com/ the code looked like this: /* Standalone ports forward only to DSA tag_8021q CPU ports */ unsigned long mask = cpu_fwd_mask; (...) } else if (ocelot->bridge_fwd_mask & BIT(port)) { mask |= ocelot->bridge_fwd_mask & ~BIT(port); while in v8 (the merged version) https://patchwork.kernel.org/project/netdevbpf/patch/20210129010009.3959398-12-olteanv@gmail.com/ it looked like this: unsigned long mask; (...) } else if (ocelot->bridge_fwd_mask & BIT(port)) { mask = ocelot->bridge_fwd_mask & ~BIT(port); So the breakage was introduced between v7 and v8 of the patch. Fixes: e21268efbe26 ("net: dsa: felix: perform switch setup for tag_8021q") Signed-off-by: Vladimir Oltean Link: https://lore.kernel.org/r/20210817160425.3702809-1-vladimir.oltean@nxp.com Signed-off-by: Jakub Kicinski