summaryrefslogtreecommitdiff
path: root/net/dsa/dsa.c
AgeCommit message (Collapse)Author
2026-01-21net: dsa: fix off-by-one in maximum bridge ID determinationVladimir Oltean
Prior to the blamed commit, the bridge_num range was from 0 to ds->max_num_bridges - 1. After the commit, it is from 1 to ds->max_num_bridges. So this check: if (bridge_num >= max) return 0; must be updated to: if (bridge_num > max) return 0; in order to allow the last bridge_num value (==max) to be used. This is easiest visible when a driver sets ds->max_num_bridges=1. The observed behaviour is that even the first created bridge triggers the netlink extack "Range of offloadable bridges exceeded" warning, and is handled in software rather than being offloaded. Fixes: 3f9bb0301d50 ("net: dsa: make dp->bridge_num one-based") Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Link: https://patch.msgid.link/20260120211039.3228999-1-vladimir.oltean@nxp.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-12-23net: dsa: fix missing put_device() in dsa_tree_find_first_conduit()Vladimir Oltean
of_find_net_device_by_node() searches net devices by their /sys/class/net/, entry. It is documented in its kernel-doc that: * If successful, returns a pointer to the net_device with the embedded * struct device refcount incremented by one, or NULL on failure. The * refcount must be dropped when done with the net_device. We are missing a put_device(&conduit->dev) which we could place at the end of dsa_tree_find_first_conduit(). But to explain why calling put_device() right away is safe is the same as to explain why the chosen solution is different. The code is very poorly split: dsa_tree_find_first_conduit() was first introduced in commit 95f510d0b792 ("net: dsa: allow the DSA master to be seen and changed through rtnetlink") but was first used several commits later, in commit acc43b7bf52a ("net: dsa: allow masters to join a LAG"). Assume there is a switch with 2 CPU ports and 2 conduits, eno2 and eno3. When we create a LAG (bonding or team device) and place eno2 and eno3 beneath it, we create a 3rd conduit (the LAG device itself), but this is slightly different than the first two. Namely, the cpu_dp->conduit pointer of the CPU ports does not change, and remains pointing towards the physical Ethernet controllers which are now LAG ports. Only 2 things change: - the LAG device has a dev->dsa_ptr which marks it as a DSA conduit - dsa_port_to_conduit(user port) finds the LAG and not the physical conduit, because of the dp->cpu_port_in_lag bit being set. When the LAG device is destroyed, dsa_tree_migrate_ports_from_lag_conduit() is called and this is where dsa_tree_find_first_conduit() kicks in. This is the logical mistake and the reason why introducing code in one patch and using it from another is bad practice. I didn't realize that I don't have to call of_find_net_device_by_node() again; the cpu_dp->conduit association was never undone, and is still available for direct (re)use. There's only one concern - maybe the conduit disappeared in the meantime, but the netdev_hold() call we made during dsa_port_parse_cpu() (see previous change) ensures that this was not the case. Therefore, fixing the code means reimplementing it in the simplest way. I am blaming the time of use, since this is what "git blame" would show if we were to monitor for the conduit's kobject's refcount remaining elevated instead of being freed. Tested on the NXP LS1028A, using the steps from Documentation/networking/dsa/configuration.rst section "Affinity of user ports to CPU ports", followed by (extra prints added by me): $ ip link del bond0 mscc_felix 0000:00:00.5 swp3: Link is Down bond0 (unregistering): (slave eno2): Releasing backup interface fsl_enetc 0000:00:00.2 eno2: Link is Down mscc_felix 0000:00:00.5 swp0: bond0 disappeared, migrating to eno2 mscc_felix 0000:00:00.5 swp1: bond0 disappeared, migrating to eno2 mscc_felix 0000:00:00.5 swp2: bond0 disappeared, migrating to eno2 mscc_felix 0000:00:00.5 swp3: bond0 disappeared, migrating to eno2 Fixes: acc43b7bf52a ("net: dsa: allow masters to join a LAG") Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Link: https://patch.msgid.link/20251215150236.3931670-2-vladimir.oltean@nxp.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-12-23net: dsa: properly keep track of conduit referenceVladimir Oltean
Problem description ------------------- DSA has a mumbo-jumbo of reference handling of the conduit net device and its kobject which, sadly, is just wrong and doesn't make sense. There are two distinct problems. 1. The OF path, which uses of_find_net_device_by_node(), never releases the elevated refcount on the conduit's kobject. Nominally, the OF and non-OF paths should result in objects having identical reference counts taken, and it is already suspicious that dsa_dev_to_net_device() has a put_device() call which is missing in dsa_port_parse_of(), but we can actually even verify that an issue exists. With CONFIG_DEBUG_KOBJECT_RELEASE=y, if we run this command "before" and "after" applying this patch: (unbind the conduit driver for net device eno2) echo 0000:00:00.2 > /sys/bus/pci/drivers/fsl_enetc/unbind we see these lines in the output diff which appear only with the patch applied: kobject: 'eno2' (ffff002009a3a6b8): kobject_release, parent 0000000000000000 (delayed 1000) kobject: '109' (ffff0020099d59a0): kobject_release, parent 0000000000000000 (delayed 1000) 2. After we find the conduit interface one way (OF) or another (non-OF), it can get unregistered at any time, and DSA remains with a long-lived, but in this case stale, cpu_dp->conduit pointer. Holding the net device's underlying kobject isn't actually of much help, it just prevents it from being freed (but we never need that kobject directly). What helps us to prevent the net device from being unregistered is the parallel netdev reference mechanism (dev_hold() and dev_put()). Actually we actually use that netdev tracker mechanism implicitly on user ports since commit 2f1e8ea726e9 ("net: dsa: link interfaces with the DSA master to get rid of lockdep warnings"), via netdev_upper_dev_link(). But time still passes at DSA switch probe time between the initial of_find_net_device_by_node() code and the user port creation time, time during which the conduit could unregister itself and DSA wouldn't know about it. So we have to run of_find_net_device_by_node() under rtnl_lock() to prevent that from happening, and release the lock only with the netdev tracker having acquired the reference. Do we need to keep the reference until dsa_unregister_switch() / dsa_switch_shutdown()? 1: Maybe yes. A switch device will still be registered even if all user ports failed to probe, see commit 86f8b1c01a0a ("net: dsa: Do not make user port errors fatal"), and the cpu_dp->conduit pointers remain valid. I haven't audited all call paths to see whether they will actually use the conduit in lack of any user port, but if they do, it seems safer to not rely on user ports for that reference. 2. Definitely yes. We support changing the conduit which a user port is associated to, and we can get into a situation where we've moved all user ports away from a conduit, thus no longer hold any reference to it via the net device tracker. But we shouldn't let it go nonetheless - see the next change in relation to dsa_tree_find_first_conduit() and LAG conduits which disappear. We have to be prepared to return to the physical conduit, so the CPU port must explicitly keep another reference to it. This is also to say: the user ports and their CPU ports may not always keep a reference to the same conduit net device, and both are needed. As for the conduit's kobject for the /sys/class/net/ entry, we don't care about it, we can release it as soon as we hold the net device object itself. History and blame attribution ----------------------------- The code has been refactored so many times, it is very difficult to follow and properly attribute a blame, but I'll try to make a short history which I hope to be correct. We have two distinct probing paths: - one for OF, introduced in 2016 in commit 83c0afaec7b7 ("net: dsa: Add new binding implementation") - one for non-OF, introduced in 2017 in commit 71e0bbde0d88 ("net: dsa: Add support for platform data") These are both complete rewrites of the original probing paths (which used struct dsa_switch_driver and other weird stuff, instead of regular devices on their respective buses for register access, like MDIO, SPI, I2C etc): - one for OF, introduced in 2013 in commit 5e95329b701c ("dsa: add device tree bindings to register DSA switches") - one for non-OF, introduced in 2008 in commit 91da11f870f0 ("net: Distributed Switch Architecture protocol support") except for tiny bits and pieces like dsa_dev_to_net_device() which were seemingly carried over since the original commit, and used to this day. The point is that the original probing paths received a fix in 2015 in the form of commit 679fb46c5785 ("net: dsa: Add missing master netdev dev_put() calls"), but the fix never made it into the "new" (dsa2) probing paths that can still be traced to today, and the fixed probing path was later deleted in 2019 in commit 93e86b3bc842 ("net: dsa: Remove legacy probing support"). That is to say, the new probing paths were never quite correct in this area. The existence of the legacy probing support which was deleted in 2019 explains why dsa_dev_to_net_device() returns a conduit with elevated refcount (because it was supposed to be released during dsa_remove_dst()). After the removal of the legacy code, the only user of dsa_dev_to_net_device() calls dev_put(conduit) immediately after this function returns. This pattern makes no sense today, and can only be interpreted historically to understand why dev_hold() was there in the first place. Change details -------------- Today we have a better netdev tracking infrastructure which we should use. Logically netdev_hold() belongs in common code (dsa_port_parse_cpu(), where dp->conduit is assigned), but there is a tradeoff to be made with the rtnl_lock() section which would become a bit too long if we did that - dsa_port_parse_cpu() also calls request_module(). So we duplicate a bit of logic in order for the callers of dsa_port_parse_cpu() to be the ones responsible of holding the conduit reference and releasing it on error. This shortens the rtnl_lock() section significantly. In the dsa_switch_probe() error path, dsa_switch_release_ports() will be called in a number of situations, one being where dsa_port_parse_cpu() maybe didn't get the chance to run at all (a different port failed earlier, etc). So we have to test for the conduit being NULL prior to calling netdev_put(). There have still been so many transformations to the code since the blamed commits (rename master -> conduit, commit 0650bf52b31f ("net: dsa: be compatible with masters which unregister on shutdown")), that it only makes sense to fix the code using the best methods available today and see how it can be backported to stable later. I suspect the fix cannot even be backported to kernels which lack dsa_switch_shutdown(), and I suspect this is also maybe why the long-lived conduit reference didn't make it into the new DSA probing paths at the time (problems during shutdown). Because dsa_dev_to_net_device() has a single call site and has to be changed anyway, the logic was just absorbed into the non-OF dsa_port_parse(). Tested on the ocelot/felix switch and on dsa_loop, both on the NXP LS1028A with CONFIG_DEBUG_KOBJECT_RELEASE=y. Reported-by: Ma Ke <make24@iscas.ac.cn> Closes: https://lore.kernel.org/netdev/20251214131204.4684-1-make24@iscas.ac.cn/ Fixes: 83c0afaec7b7 ("net: dsa: Add new binding implementation") Fixes: 71e0bbde0d88 ("net: dsa: Add support for platform data") Reviewed-by: Jonas Gorski <jonas.gorski@gmail.com> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Link: https://patch.msgid.link/20251215150236.3931670-1-vladimir.oltean@nxp.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-12-01net: dsa: add simple HSR offload helpersVladimir Oltean
It turns out that HSR offloads are so fine-grained that many DSA switches can do a small part even though they weren't specifically designed for the protocols supported by that driver (HSR and PRP). Specifically NETIF_F_HW_HSR_DUP - it is simple packet duplication on transmit, towards all (aka 2) ports members of the HSR device. For many DSA switches, we know how to duplicate a packet, even though we never typically use that feature. The transmit port mask from the tagging protocol can have multiple bits set, and the switch should send the packet once to every port with a bit set from that mask. Nonetheless, not all tagging protocols are like this, and sometimes the port is a single numeric value rather than a bit mask. For that reason, and also because switches can sometimes change tagging protocols for different ones, we need to make HSR offload helpers opt-in. For devices that can do nothing else HSR-specific, we introduce dsa_port_simple_hsr_join() and dsa_port_simple_hsr_leave(). These functions monitor when two user ports of the same switch are part of the same HSR device, and when that condition is true, they toggle the NETIF_F_HW_HSR_DUP feature flag of both net devices. Normally only dsa_port_simple_hsr_join() and dsa_port_simple_hsr_leave() are needed. The dsa_port_simple_hsr_validate() helper is just to see what kind of configuration could be offloadable using the generic helpers. This is used by switch drivers which are not currently using the right tagging protocol to offload this HSR ring, but could in principle offload it after changing the tagger. Suggested-by: David Yang <mmyangfl@gmail.com> Cc: "Alvin Šipraga" <alsi@bang-olufsen.dk> Cc: Chester A. Unal" <chester.a.unal@arinc9.com> Cc: "Clément Léger" <clement.leger@bootlin.com> Cc: Daniel Golle <daniel@makrotopia.org> Cc: DENG Qingfang <dqfext@gmail.com> Cc: Florian Fainelli <florian.fainelli@broadcom.com> Cc: George McCollister <george.mccollister@gmail.com> Cc: Hauke Mehrtens <hauke@hauke-m.de> Cc: Jonas Gorski <jonas.gorski@gmail.com> Cc: Kurt Kanzenbach <kurt@linutronix.de> Cc: Linus Walleij <linus.walleij@linaro.org> Cc: Sean Wang <sean.wang@mediatek.com> Cc: UNGLinuxDriver@microchip.com Cc: Woojung Huh <woojung.huh@microchip.com> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Link: https://patch.msgid.link/20251130131657.65080-6-vladimir.oltean@nxp.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-07-18net: s/dev_close_many/netif_close_many/Stanislav Fomichev
Commit cc34acd577f1 ("docs: net: document new locking reality") introduced netif_ vs dev_ function semantics: the former expects locked netdev, the latter takes care of the locking. We don't strictly follow this semantics on either side, but there are more dev_xxx handlers now that don't fit. Rename them to netif_xxx where appropriate. netif_close_many is used only by vlan/dsa and one mtk driver, so move it into NETDEV_INTERNAL namespace. Signed-off-by: Stanislav Fomichev <sdf@fomichev.me> Link: https://patch.msgid.link/20250717172333.1288349-8-sdf@fomichev.me Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-04-16net: dsa: free routing table on probe failureVladimir Oltean
If complete = true in dsa_tree_setup(), it means that we are the last switch of the tree which is successfully probing, and we should be setting up all switches from our probe path. After "complete" becomes true, dsa_tree_setup_cpu_ports() or any subsequent function may fail. If that happens, the entire tree setup is in limbo: the first N-1 switches have successfully finished probing (doing nothing but having allocated persistent memory in the tree's dst->ports, and maybe dst->rtable), and switch N failed to probe, ending the tree setup process before anything is tangible from the user's PoV. If switch N fails to probe, its memory (ports) will be freed and removed from dst->ports. However, the dst->rtable elements pointing to its ports, as created by dsa_link_touch(), will remain there, and will lead to use-after-free if dereferenced. If dsa_tree_setup_switches() returns -EPROBE_DEFER, which is entirely possible because that is where ds->ops->setup() is, we get a kasan report like this: ================================================================== BUG: KASAN: slab-use-after-free in mv88e6xxx_setup_upstream_port+0x240/0x568 Read of size 8 at addr ffff000004f56020 by task kworker/u8:3/42 Call trace: __asan_report_load8_noabort+0x20/0x30 mv88e6xxx_setup_upstream_port+0x240/0x568 mv88e6xxx_setup+0xebc/0x1eb0 dsa_register_switch+0x1af4/0x2ae0 mv88e6xxx_register_switch+0x1b8/0x2a8 mv88e6xxx_probe+0xc4c/0xf60 mdio_probe+0x78/0xb8 really_probe+0x2b8/0x5a8 __driver_probe_device+0x164/0x298 driver_probe_device+0x78/0x258 __device_attach_driver+0x274/0x350 Allocated by task 42: __kasan_kmalloc+0x84/0xa0 __kmalloc_cache_noprof+0x298/0x490 dsa_switch_touch_ports+0x174/0x3d8 dsa_register_switch+0x800/0x2ae0 mv88e6xxx_register_switch+0x1b8/0x2a8 mv88e6xxx_probe+0xc4c/0xf60 mdio_probe+0x78/0xb8 really_probe+0x2b8/0x5a8 __driver_probe_device+0x164/0x298 driver_probe_device+0x78/0x258 __device_attach_driver+0x274/0x350 Freed by task 42: __kasan_slab_free+0x48/0x68 kfree+0x138/0x418 dsa_register_switch+0x2694/0x2ae0 mv88e6xxx_register_switch+0x1b8/0x2a8 mv88e6xxx_probe+0xc4c/0xf60 mdio_probe+0x78/0xb8 really_probe+0x2b8/0x5a8 __driver_probe_device+0x164/0x298 driver_probe_device+0x78/0x258 __device_attach_driver+0x274/0x350 The simplest way to fix the bug is to delete the routing table in its entirety. dsa_tree_setup_routing_table() has no problem in regenerating it even if we deleted links between ports other than those of switch N, because dsa_link_touch() first checks whether the port pair already exists in dst->rtable, allocating if not. The deletion of the routing table in its entirety already exists in dsa_tree_teardown(), so refactor that into a function that can also be called from the tree setup error path. In my analysis of the commit to blame, it is the one which added dsa_link elements to dst->rtable. Prior to that, each switch had its own ds->rtable which is freed when the switch fails to probe. But the tree is potentially persistent memory. Fixes: c5f51765a1f6 ("net: dsa: list DSA links in the fabric") Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Link: https://patch.msgid.link/20250414213001.2957964-1-vladimir.oltean@nxp.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-04-16net: dsa: clean up FDB, MDB, VLAN entries on unbindVladimir Oltean
As explained in many places such as commit b117e1e8a86d ("net: dsa: delete dsa_legacy_fdb_add and dsa_legacy_fdb_del"), DSA is written given the assumption that higher layers have balanced additions/deletions. As such, it only makes sense to be extremely vocal when those assumptions are violated and the driver unbinds with entries still present. But Ido Schimmel points out a very simple situation where that is wrong: https://lore.kernel.org/netdev/ZDazSM5UsPPjQuKr@shredder/ (also briefly discussed by me in the aforementioned commit). Basically, while the bridge bypass operations are not something that DSA explicitly documents, and for the majority of DSA drivers this API simply causes them to go to promiscuous mode, that isn't the case for all drivers. Some have the necessary requirements for bridge bypass operations to do something useful - see dsa_switch_supports_uc_filtering(). Although in tools/testing/selftests/net/forwarding/local_termination.sh, we made an effort to popularize better mechanisms to manage address filters on DSA interfaces from user space - namely macvlan for unicast, and setsockopt(IP_ADD_MEMBERSHIP) - through mtools - for multicast, the fact is that 'bridge fdb add ... self static local' also exists as kernel UAPI, and might be useful to someone, even if only for a quick hack. It seems counter-productive to block that path by implementing shim .ndo_fdb_add and .ndo_fdb_del operations which just return -EOPNOTSUPP in order to prevent the ndo_dflt_fdb_add() and ndo_dflt_fdb_del() from running, although we could do that. Accepting that cleanup is necessary seems to be the only option. Especially since we appear to be coming back at this from a different angle as well. Russell King is noticing that the WARN_ON() triggers even for VLANs: https://lore.kernel.org/netdev/Z_li8Bj8bD4-BYKQ@shell.armlinux.org.uk/ What happens in the bug report above is that dsa_port_do_vlan_del() fails, then the VLAN entry lingers on, and then we warn on unbind and leak it. This is not a straight revert of the blamed commit, but we now add an informational print to the kernel log (to still have a way to see that bugs exist), and some extra comments gathered from past years' experience, to justify the logic. Fixes: 0832cd9f1f02 ("net: dsa: warn if port lists aren't empty in dsa_port_teardown") Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Link: https://patch.msgid.link/20250414212930.2956310-1-vladimir.oltean@nxp.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-01-03driver core: Constify API device_find_child() and adapt for various usagesZijun Hu
Constify the following API: struct device *device_find_child(struct device *dev, void *data, int (*match)(struct device *dev, void *data)); To : struct device *device_find_child(struct device *dev, const void *data, device_match_t match); typedef int (*device_match_t)(struct device *dev, const void *data); with the following reasons: - Protect caller's match data @*data which is for comparison and lookup and the API does not actually need to modify @*data. - Make the API's parameters (@match)() and @data have the same type as all of other device finding APIs (bus|class|driver)_find_device(). - All kinds of existing device match functions can be directly taken as the API's argument, they were exported by driver core. Constify the API and adapt for various existing usages. BTW, various subsystem changes are squashed into this commit to meet 'git bisect' requirement, and this commit has the minimal and simplest changes to complement squashing shortcoming, and that may bring extra code improvement. Reviewed-by: Alison Schofield <alison.schofield@intel.com> Reviewed-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Acked-by: Uwe Kleine-König <ukleinek@kernel.org> # for drivers/pwm Signed-off-by: Zijun Hu <quic_zijuhu@quicinc.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org> Link: https://lore.kernel.org/r/20241224-const_dfc_done-v5-4-6623037414d4@quicinc.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-10-07net: dsa: remove obsolete phylink dsa_switch operationsRussell King (Oracle)
No driver now uses the DSA switch phylink members, so we can now remove the method pointers, but we need to leave empty shim functions to allow those drivers that do not provide phylink MAC operations structure to continue functioning. Signed-off-by: Russell King (oracle) <rmk+kernel@armlinux.org.uk> Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com> Tested-by: Vladimir Oltean <vladimir.oltean@nxp.com> # sja1105, felix, dsa_loop Link: https://patch.msgid.link/E1swKNV-0060oN-1b@rmk-PC.armlinux.org.uk Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-10-01net: dsa: improve shutdown sequenceVladimir Oltean
Alexander Sverdlin presents 2 problems during shutdown with the lan9303 driver. One is specific to lan9303 and the other just happens to reproduce there. The first problem is that lan9303 is unique among DSA drivers in that it calls dev_get_drvdata() at "arbitrary runtime" (not probe, not shutdown, not remove): phy_state_machine() -> ... -> dsa_user_phy_read() -> ds->ops->phy_read() -> lan9303_phy_read() -> chip->ops->phy_read() -> lan9303_mdio_phy_read() -> dev_get_drvdata() But we never stop the phy_state_machine(), so it may continue to run after dsa_switch_shutdown(). Our common pattern in all DSA drivers is to set drvdata to NULL to suppress the remove() method that may come afterwards. But in this case it will result in an NPD. The second problem is that the way in which we set dp->conduit->dsa_ptr = NULL; is concurrent with receive packet processing. dsa_switch_rcv() checks once whether dev->dsa_ptr is NULL, but afterwards, rather than continuing to use that non-NULL value, dev->dsa_ptr is dereferenced again and again without NULL checks: dsa_conduit_find_user() and many other places. In between dereferences, there is no locking to ensure that what was valid once continues to be valid. Both problems have the common aspect that closing the conduit interface solves them. In the first case, dev_close(conduit) triggers the NETDEV_GOING_DOWN event in dsa_user_netdevice_event() which closes user ports as well. dsa_port_disable_rt() calls phylink_stop(), which synchronously stops the phylink state machine, and ds->ops->phy_read() will thus no longer call into the driver after this point. In the second case, dev_close(conduit) should do this, as per Documentation/networking/driver.rst: | Quiescence | ---------- | | After the ndo_stop routine has been called, the hardware must | not receive or transmit any data. All in flight packets must | be aborted. If necessary, poll or wait for completion of | any reset commands. So it should be sufficient to ensure that later, when we zeroize conduit->dsa_ptr, there will be no concurrent dsa_switch_rcv() call on this conduit. The addition of the netif_device_detach() function is to ensure that ioctls, rtnetlinks and ethtool requests on the user ports no longer propagate down to the driver - we're no longer prepared to handle them. The race condition actually did not exist when commit 0650bf52b31f ("net: dsa: be compatible with masters which unregister on shutdown") first introduced dsa_switch_shutdown(). It was created later, when we stopped unregistering the user interfaces from a bad spot, and we just replaced that sequence with a racy zeroization of conduit->dsa_ptr (one which doesn't ensure that the interfaces aren't up). Reported-by: Alexander Sverdlin <alexander.sverdlin@siemens.com> Closes: https://lore.kernel.org/netdev/2d2e3bba17203c14a5ffdabc174e3b6bbb9ad438.camel@siemens.com/ Closes: https://lore.kernel.org/netdev/c1bf4de54e829111e0e4a70e7bd1cf523c9550ff.camel@siemens.com/ Fixes: ee534378f005 ("net: dsa: fix panic when DSA master device unbinds on shutdown") Reviewed-by: Alexander Sverdlin <alexander.sverdlin@siemens.com> Tested-by: Alexander Sverdlin <alexander.sverdlin@siemens.com> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Link: https://patch.msgid.link/20240913203549.3081071-1-vladimir.oltean@nxp.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-05-29net: dsa: remove mac_prepare()/mac_finish() shimsRussell King (Oracle)
No DSA driver makes use of the mac_prepare()/mac_finish() shimmed operations anymore, so we can remove these. Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com> Link: https://lore.kernel.org/r/E1sByNx-00ELW1-Vp@rmk-PC.armlinux.org.uk Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-01net: dsa: Remove adjust_link pathsFlorian Fainelli
Now that we no longer any drivers using PHYLIB's adjust_link callback, remove all paths that made use of adjust_link as well as the associated functions. Signed-off-by: Florian Fainelli <florian.fainelli@broadcom.com> Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Link: https://lore.kernel.org/r/20240430164816.2400606-3-florian.fainelli@broadcom.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-04-11net: dsa: allow DSA switch drivers to provide their own phylink mac opsRussell King (Oracle)
Rather than having a shim for each and every phylink MAC operation, allow DSA switch drivers to provide their own ops structure. When a DSA driver provides the phylink MAC operations, the shimmed ops must not be provided, so fail an attempt to register a switch with both the phylink_mac_ops in struct dsa_switch and the phylink_mac_* operations populated in dsa_switch_ops populated. Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Reviewed-by: Vladimir Oltean <olteanv@gmail.com> Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com> Link: https://lore.kernel.org/r/E1rudqF-006K9H-Cc@rmk-PC.armlinux.org.uk Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-02-15net: dsa: remove OF-based MDIO bus registration from DSA coreArınç ÜNAL
The code block under the "!ds->user_mii_bus && ds->ops->phy_read" check under dsa_switch_setup() populates ds->user_mii_bus. The use of ds->user_mii_bus is inappropriate when the MDIO bus of the switch is described on the device tree [1]. For this reason, use this code block only for switches [with MDIO bus] probed on platform_data, and OF which the switch MDIO bus isn't described on the device tree. Therefore, remove OF-based MDIO bus registration as it's useless for these cases. These subdrivers which control switches [with MDIO bus] probed on OF, will lose the ability to register the MDIO bus OF-based: drivers/net/dsa/b53/b53_common.c drivers/net/dsa/lan9303-core.c drivers/net/dsa/vitesse-vsc73xx-core.c These subdrivers let the DSA core driver register the bus: - ds->ops->phy_read() and ds->ops->phy_write() are present. - ds->user_mii_bus is not populated. The commit fe7324b93222 ("net: dsa: OF-ware slave_mii_bus") which brought OF-based MDIO bus registration on the DSA core driver is reasonably recent and, in this time frame, there have been no device trees in the Linux repository that started describing the MDIO bus, or dt-bindings defining the MDIO bus for the switches these subdrivers control. So I don't expect any devices to be affected. The logic we encourage is that all subdrivers should register the switch MDIO bus on their own [2]. And, for subdrivers which control switches [with MDIO bus] probed on OF, this logic must be followed to support all cases properly: No switch MDIO bus defined: Populate ds->user_mii_bus, register the MDIO bus, set the interrupts for PHYs if "interrupt-controller" is defined at the switch node. This case should only be covered for the switches which their dt-bindings documentation didn't document the MDIO bus from the start. This is to keep supporting the device trees that do not describe the MDIO bus on the device tree but the MDIO bus is being used nonetheless. Switch MDIO bus defined: Don't populate ds->user_mii_bus, register the MDIO bus, set the interrupts for PHYs if ["interrupt-controller" is defined at the switch node and "interrupts" is defined at the PHY nodes under the switch MDIO bus node]. Switch MDIO bus defined but explicitly disabled: If the device tree says status = "disabled" for the MDIO bus, we shouldn't need an MDIO bus at all. Instead, just exit as early as possible and do not call any MDIO API. After all subdrivers that control switches with MDIO buses are made to register the MDIO buses on their own, we will be able to get rid of dsa_switch_ops :: phy_read() and :: phy_write(), and the code block for registering the MDIO bus on the DSA core driver. Link: https://lore.kernel.org/netdev/20231213120656.x46fyad6ls7sqyzv@skbuf/ [1] Link: https://lore.kernel.org/netdev/20240103184459.dcbh57wdnlox6w7d@skbuf/ [2] Suggested-by: Luiz Angelo Daros de Luca <luizluca@gmail.com> Acked-by: Luiz Angelo Daros de Luca <luizluca@gmail.com> Signed-off-by: Arınç ÜNAL <arinc.unal@arinc9.com> Reviewed-by: Vladimir Oltean <olteanv@gmail.com> Link: https://lore.kernel.org/r/20240213-for-netnext-dsa-mdio-bus-v2-1-0ff6f4823a9e@arinc9.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-10-24net: dsa: Use conduit and user termsFlorian Fainelli
Use more inclusive terms throughout the DSA subsystem by moving away from "master" which is replaced by "conduit" and "slave" which is replaced by "user". No functional changes. Acked-by: Rob Herring <robh@kernel.org> Acked-by: Stephen Hemminger <stephen@networkplumber.org> Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: Florian Fainelli <florian.fainelli@broadcom.com> Link: https://lore.kernel.org/r/20231023181729.1191071-2-florian.fainelli@broadcom.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-27net: dsa: avoid suspicious RCU usage for synced VLAN-aware MAC addressesVladimir Oltean
When using the felix driver (the only one which supports UC filtering and MC filtering) as a DSA master for a random other DSA switch, one can see the following stack trace when the downstream switch ports join a VLAN-aware bridge: ============================= WARNING: suspicious RCU usage ----------------------------- net/8021q/vlan_core.c:238 suspicious rcu_dereference_protected() usage! stack backtrace: Workqueue: dsa_ordered dsa_slave_switchdev_event_work Call trace: lockdep_rcu_suspicious+0x170/0x210 vlan_for_each+0x8c/0x188 dsa_slave_sync_uc+0x128/0x178 __hw_addr_sync_dev+0x138/0x158 dsa_slave_set_rx_mode+0x58/0x70 __dev_set_rx_mode+0x88/0xa8 dev_uc_add+0x74/0xa0 dsa_port_bridge_host_fdb_add+0xec/0x180 dsa_slave_switchdev_event_work+0x7c/0x1c8 process_one_work+0x290/0x568 What it's saying is that vlan_for_each() expects rtnl_lock() context and it's not getting it, when it's called from the DSA master's ndo_set_rx_mode(). The caller of that - dsa_slave_set_rx_mode() - is the slave DSA interface's dsa_port_bridge_host_fdb_add() which comes from the deferred dsa_slave_switchdev_event_work(). We went to great lengths to avoid the rtnl_lock() context in that call path in commit 0faf890fc519 ("net: dsa: drop rtnl_lock from dsa_slave_switchdev_event_work"), and calling rtnl_lock() is simply not an option due to the possibility of deadlocking when calling dsa_flush_workqueue() from the call paths that do hold rtnl_lock() - basically all of them. So, when the DSA master calls vlan_for_each() from its ndo_set_rx_mode(), the state of the 8021q driver on this device is really not protected from concurrent access by anything. Looking at net/8021q/, I don't think that vlan_info->vid_list was particularly designed with RCU traversal in mind, so introducing an RCU read-side form of vlan_for_each() - vlan_for_each_rcu() - won't be so easy, and it also wouldn't be exactly what we need anyway. In general I believe that the solution isn't in net/8021q/ anyway; vlan_for_each() is not cut out for this task. DSA doesn't need rtnl_lock() to be held per se - since it's not a netdev state change that we're blocking, but rather, just concurrent additions/removals to a VLAN list. We don't even need sleepable context - the callback of vlan_for_each() just schedules deferred work. The proposed escape is to remove the dependency on vlan_for_each() and to open-code a non-sleepable, rtnl-free alternative to that, based on copies of the VLAN list modified from .ndo_vlan_rx_add_vid() and .ndo_vlan_rx_kill_vid(). Fixes: 64fdc5f341db ("net: dsa: sync unicast and multicast addresses for VLAN filters too") Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Link: https://lore.kernel.org/r/20230626154402.3154454-1-vladimir.oltean@nxp.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-20net: dsa: introduce preferred_default_local_cpu_port and use on MT7530Vladimir Oltean
Since the introduction of the OF bindings, DSA has always had a policy that in case multiple CPU ports are present in the device tree, the numerically smallest one is always chosen. The MT7530 switch family, except the switch on the MT7988 SoC, has 2 CPU ports, 5 and 6, where port 6 is preferable on the MT7531BE switch because it has higher bandwidth. The MT7530 driver developers had 3 options: - to modify DSA when the MT7531 switch support was introduced, such as to prefer the better port - to declare both CPU ports in device trees as CPU ports, and live with the sub-optimal performance resulting from not preferring the better port - to declare just port 6 in the device tree as a CPU port Of course they chose the path of least resistance (3rd option), kicking the can down the road. The hardware description in the device tree is supposed to be stable - developers are not supposed to adopt the strategy of piecemeal hardware description, where the device tree is updated in lockstep with the features that the kernel currently supports. Now, as a result of the fact that they did that, any attempts to modify the device tree and describe both CPU ports as CPU ports would make DSA change its default selection from port 6 to 5, effectively resulting in a performance degradation visible to users with the MT7531BE switch as can be seen below. Without preferring port 6: [ ID][Role] Interval Transfer Bitrate Retr [ 5][TX-C] 0.00-20.00 sec 374 MBytes 157 Mbits/sec 734 sender [ 5][TX-C] 0.00-20.00 sec 373 MBytes 156 Mbits/sec receiver [ 7][RX-C] 0.00-20.00 sec 1.81 GBytes 778 Mbits/sec 0 sender [ 7][RX-C] 0.00-20.00 sec 1.81 GBytes 777 Mbits/sec receiver With preferring port 6: [ ID][Role] Interval Transfer Bitrate Retr [ 5][TX-C] 0.00-20.00 sec 1.99 GBytes 856 Mbits/sec 273 sender [ 5][TX-C] 0.00-20.00 sec 1.99 GBytes 855 Mbits/sec receiver [ 7][RX-C] 0.00-20.00 sec 1.72 GBytes 737 Mbits/sec 15 sender [ 7][RX-C] 0.00-20.00 sec 1.71 GBytes 736 Mbits/sec receiver Using one port for WAN and the other ports for LAN is a very popular use case which is what this test emulates. As such, this change proposes that we retroactively modify stable kernels (which don't support the modification of the CPU port assignments, so as to let user space fix the problem and restore the throughput) to keep the mt7530 driver preferring port 6 even with device trees where the hardware is more fully described. Fixes: c288575f7810 ("net: dsa: mt7530: Add the support of MT7531 switch") Signed-off-by: Vladimir Oltean <olteanv@gmail.com> Signed-off-by: Arınç ÜNAL <arinc.unal@arinc9.com> Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-04-09net: dsa: replace NETDEV_PRE_CHANGE_HWTSTAMP notifier with a stubVladimir Oltean
There was a sort of rush surrounding commit 88c0a6b503b7 ("net: create a netdev notifier for DSA to reject PTP on DSA master"), due to a desire to convert DSA's attempt to deny TX timestamping on a DSA master to something that doesn't block the kernel-wide API conversion from ndo_eth_ioctl() to ndo_hwtstamp_set(). What was required was a mechanism that did not depend on ndo_eth_ioctl(), and what was provided was a mechanism that did not depend on ndo_eth_ioctl(), while at the same time introducing something that wasn't absolutely necessary - a new netdev notifier. There have been objections from Jakub Kicinski that using notifiers in general when they are not absolutely necessary creates complications to the control flow and difficulties to maintainers who look at the code. So there is a desire to not use notifiers. In addition to that, the notifier chain gets called even if there is no DSA in the system and no one is interested in applying any restriction. Take the model of udp_tunnel_nic_ops and introduce a stub mechanism, through which net/core/dev_ioctl.c can call into DSA even when CONFIG_NET_DSA=m. Compared to the code that existed prior to the notifier conversion, aka what was added in commits: - 4cfab3566710 ("net: dsa: Add wrappers for overloaded ndo_ops") - 3369afba1e46 ("net: Call into DSA netdevice_ops wrappers") this is different because we are not overloading any struct net_device_ops of the DSA master anymore, but rather, we are exposing a rather specific functionality which is orthogonal to which API is used to enable it - ndo_eth_ioctl() or ndo_hwtstamp_set(). Also, what is similar is that both approaches use function pointers to get from built-in code to DSA. There is no point in replicating the function pointers towards __dsa_master_hwtstamp_validate() once for every CPU port (dev->dsa_ptr). Instead, it is sufficient to introduce a singleton struct dsa_stubs, built into the kernel, which contains a single function pointer to __dsa_master_hwtstamp_validate(). I find this approach preferable to what we had originally, because dev->dsa_ptr->netdev_ops->ndo_do_ioctl() used to require going through struct dsa_port (dev->dsa_ptr), and so, this was incompatible with any attempts to add any data encapsulation and hide DSA data structures from the outside world. Link: https://lore.kernel.org/netdev/20230403083019.120b72fd@kernel.org/ Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-11-22net: dsa: kill off dsa_priv.hVladimir Oltean
The last remnants in dsa_priv.h are a netlink-related definition for which we create a new header, and DSA_MAX_NUM_OFFLOADING_BRIDGES which is only used from dsa.c, so move it there. Some inclusions need to be adjusted now that we no longer have headers included transitively from dsa_priv.h. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-11-22net: dsa: rename dsa2.c back into dsa.c and create its headerVladimir Oltean
The previous change moved the code into the larger file (dsa2.c) to minimize the delta. Rename that now to dsa.c, and create dsa.h, where all related definitions from dsa_priv.h go. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-11-22net: dsa: merge dsa.c into dsa2.cVladimir Oltean
There is no longer a meaningful distinction between what goes into dsa2.c and what goes into dsa.c. Merge the 2 into a single file. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-11-22net: dsa: move tagging protocol code to tag.{c,h}Vladimir Oltean
It would be nice if tagging protocol drivers could include just the header they need, since they are (mostly) data path and isolated from most of the other DSA core code does. Create a tag.c and a tag.h file which are meant to support tagging protocol drivers. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-11-22net: dsa: move headers exported by slave.c to slave.hVladimir Oltean
Minimize the use of the bloated dsa_priv.h by moving the prototypes exported by slave.c to their own header file. This is just approximate to get the code structure right. There are some interdependencies with static inline code left in dsa_priv.h, so leave slave.h included from there for now. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-11-22net: dsa: move bulk of devlink code to devlink.{c,h}Vladimir Oltean
dsa.c and dsa2.c are bloated with too much off-topic code. Identify all code related to devlink and move it to a new devlink.c file. Steer clear of the dsa_priv.h dumping ground antipattern and create a dedicated devlink.h for it, which will be included only by the C files which need it. Usage of dsa_priv.h will be minimized in later patches. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-11-22net: dsa: modularize DSA_TAG_PROTO_NONEVladimir Oltean
There is no reason that I can see why the no-op tagging protocol should be registered manually, so make it a module and make all drivers which have any sort of reference to DSA_TAG_PROTO_NONE select it. Note that I don't know if ksz_get_tag_protocol() really needs this, or if it's just the logic which is poorly written. All switches seem to have their own tagging protocol, and DSA_TAG_PROTO_NONE is just a fallback that never gets used. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-11-22net: dsa: unexport dsa_dev_to_net_device()Vladimir Oltean
dsa.o and dsa2.o are linked into the same dsa_core.o, there is no reason to export this symbol when its only caller is local. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-11-17net: dsa: autoload tag driver module on tagging protocol changeVladimir Oltean
Issue a request_module() call when an attempt to change the tagging protocol is made, either by sysfs or by device tree. In the case of ocelot (the only driver for which the default and the alternative tagging protocol are compiled as different modules), the user is now no longer required to insert tag_ocelot_8021q.ko manually. In the particular case of ocelot, this solves a problem where tag_ocelot_8021q.ko is built as module, and this is present in the device tree: &mscc_felix_port4 { dsa-tag-protocol = "ocelot-8021q"; }; &mscc_felix_port5 { dsa-tag-protocol = "ocelot-8021q"; }; Because no one attempts to load the module into the kernel at boot time, the switch driver will fail to probe (actually forever defer) until someone manually inserts tag_ocelot_8021q.ko. This is now no longer necessary and happens automatically. Rename dsa_find_tagger_by_name() to denote the change in functionality: there is now feature parity with dsa_tag_driver_get_by_id(), i.o.w. we also load the module if it's missing. Link: https://lore.kernel.org/lkml/20221027113248.420216-1-michael@walle.cc/ Suggested-by: Michael Walle <michael@walle.cc> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Tested-by: Michael Walle <michael@walle.cc> # on kontron-sl28 w/ ocelot_8021q Tested-by: Michael Walle <michael@walle.cc> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-11-17net: dsa: rename dsa_tag_driver_get() to dsa_tag_driver_get_by_id()Vladimir Oltean
A future patch will introduce one more way of getting a reference on a tagging protocl driver (by name). Rename the current method to "by_id". Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Tested-by: Michael Walle <michael@walle.cc> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-11-17net: dsa: strip sysfs "tagging" string of trailing newlineVladimir Oltean
Currently, dsa_find_tagger_by_name() uses sysfs_streq() which works both with strings that contain \n at the end (echo ocelot > .../dsa/tagging) and with strings that don't (printf ocelot > .../dsa/tagging). There will be a problem once we'll want to construct the modalias string based on which we auto-load the protocol kernel module. If the sysfs buffer ends in a newline, we need to strip it first. This is a preparatory patch specifically for that. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Tested-by: Michael Walle <michael@walle.cc> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-11-17net: dsa: rename tagging protocol driver modaliasVladimir Oltean
It's autumn cleanup time, and today's target are modaliases. Michael says that for users of modinfo, "dsa_tag-20" is not the most suggestive name, and recommends a change to "dsa_tag-id-20". Andrew points out that other modaliases have a prefix delimited by colons, so he recommends "dsa_tag:20" instead of "dsa_tag-20". To satisfy both proposals, Florian recommends "dsa_tag:id-20". The modaliases are not stable ABI, and the essential information (protocol ID) is still conveyed in the new string, which request_module() must be adapted to form. Link: 20221027210830.3577793-1-vladimir.oltean@nxp.com Suggested-by: Andrew Lunn <andrew@lunn.ch> Suggested-by: Michael Walle <michael@walle.cc> Suggested-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Tested-by: Michael Walle <michael@walle.cc> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-11-15net: dsa: add support for DSA rx offloading via metadata dstFelix Fietkau
If a metadata dst is present with the type METADATA_HW_PORT_MUX on a dsa cpu port netdev, assume that it carries the port number and that there is no DSA tag present in the skb data. Signed-off-by: Felix Fietkau <nbd@nbd.name> Reviewed-by: Vladimir Oltean <olteanv@gmail.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-09-20net: dsa: allow the DSA master to be seen and changed through rtnetlinkVladimir Oltean
Some DSA switches have multiple CPU ports, which can be used to improve CPU termination throughput, but DSA, through dsa_tree_setup_cpu_ports(), sets up only the first one, leading to suboptimal use of hardware. The desire is to not change the default configuration but to permit the user to create a dynamic mapping between individual user ports and the CPU port that they are served by, configurable through rtnetlink. It is also intended to permit load balancing between CPU ports, and in that case, the foreseen model is for the DSA master to be a bonding interface whose lowers are the physical DSA masters. To that end, we create a struct rtnl_link_ops for DSA user ports with the "dsa" kind. We expose the IFLA_DSA_MASTER link attribute that contains the ifindex of the newly desired DSA master. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2022-05-06net: dsa: delete dsa_port_walk_{fdbs,mdbs}Vladimir Oltean
All the users of these functions are gone, delete them before they gain new ones. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-04-25net: dsa: remove unused headersMarcin Wojtas
Reduce a number of included headers to a necessary minimum. Signed-off-by: Marcin Wojtas <mw@semihalf.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-03-09net: dsa: felix: avoid early deletion of host FDB entriesVladimir Oltean
The Felix driver declares FDB isolation but puts all standalone ports in VID 0. This is mostly problem-free as discussed with Alvin here: https://patchwork.kernel.org/project/netdevbpf/cover/20220302191417.1288145-1-vladimir.oltean@nxp.com/#24763870 however there is one catch. DSA still thinks that FDB entries are installed on the CPU port as many times as there are user ports, and this is problematic when multiple user ports share the same MAC address. Consider the default case where all user ports inherit their MAC address from the DSA master, and then the user runs: ip link set swp0 address 00:01:02:03:04:05 The above will make dsa_slave_set_mac_address() call dsa_port_standalone_host_fdb_add() for 00:01:02:03:04:05 in port 0's standalone database, and dsa_port_standalone_host_fdb_del() for the old address of swp0, again in swp0's standalone database. Both the ->port_fdb_add() and ->port_fdb_del() will be propagated down to the felix driver, which will end up deleting the old MAC address from the CPU port. But this is still in use by other user ports, so we end up breaking unicast termination for them. There isn't a problem in the fact that DSA keeps track of host standalone addresses in the individual database of each user port: some drivers like sja1105 need this. There also isn't a problem in the fact that some drivers choose the same VID/FID for all standalone ports. It is just that the deletion of these host addresses must be delayed until they are known to not be in use any longer, and only the driver has this knowledge. Since DSA keeps these addresses in &cpu_dp->fdbs and &cpu_db->mdbs, it is just a matter of walking over those lists and see whether the same MAC address is present on the CPU port in the port db of another user port. I have considered reusing the generic dsa_port_walk_fdbs() and dsa_port_walk_mdbs() schemes for this, but locking makes it difficult. In the ->port_fdb_add() method and co, &dp->addr_lists_lock is held, but dsa_port_walk_fdbs() also acquires that lock. Also, even assuming that we introduce an unlocked variant of the address iterator, we'd still need some relatively complex data structures, and a void *ctx in the dsa_fdb_walk_cb_t which we don't currently pass, such that drivers are able to figure out, after iterating, whether the same MAC address is or isn't present in the port db of another port. All the above, plus the fact that I expect other drivers to follow the same model as felix where all standalone ports use the same FID, made me conclude that a generic method provided by DSA is necessary: dsa_fdb_present_in_other_db() and the mdb equivalent. Felix calls this from the ->port_fdb_del() handler for the CPU port, when the database was classified to either a port db, or a LAG db. For symmetry, we also call this from ->port_fdb_add(), because if the address was installed once, then installing it a second time serves no purpose: it's already in hardware in VID 0 and it affects all standalone ports. This change moves dsa_db_equal() from switch.c to dsa.c, since it now has one more caller. Fixes: 54c319846086 ("net: mscc: ocelot: enforce FDB isolation when VLAN-unaware") Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-03-07net: dsa: return success if there was nothing to doTom Rix
Clang static analysis reports this representative issue dsa.c:486:2: warning: Undefined or garbage value returned to caller return err; ^~~~~~~~~~ err is only set in the loop. If the loop is empty, garbage will be returned. So initialize err to 0 to handle this noop case. Signed-off-by: Tom Rix <trix@redhat.com> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Reviewed-by: Vladimir Oltean <olteanv@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-03-03net: dsa: felix: migrate host FDB and MDB entries when changing tag protoVladimir Oltean
The "ocelot" and "ocelot-8021q" tagging protocols make use of different hardware resources, and host FDB entries have different destination ports in the switch analyzer module, practically speaking. So when the user requests a tagging protocol change, the driver must migrate all host FDB and MDB entries from the NPI port (in fact CPU port module) towards the same physical port, but this time used as a regular port. It is pointless for the felix driver to keep a copy of the host addresses, when we can create and export DSA helpers for walking through the addresses that it already needs to keep on the CPU port, for refcounting purposes. felix_classify_db() is moved up to avoid a forward declaration. We pass "bool change" because dp->fdbs and dp->mdbs are uninitialized lists when felix_setup() first calls felix_set_tag_protocol(), so we need to avoid calling dsa_port_walk_fdbs() during probe time. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-14net: dsa: mv88e6xxx: flush switchdev FDB workqueue before removing VLANVladimir Oltean
mv88e6xxx is special among DSA drivers in that it requires the VTU to contain the VID of the FDB entry it modifies in mv88e6xxx_port_db_load_purge(), otherwise it will return -EOPNOTSUPP. Sometimes due to races this is not always satisfied even if external code does everything right (first deletes the FDB entries, then the VLAN), because DSA commits to hardware FDB entries asynchronously since commit c9eb3e0f8701 ("net: dsa: Add support for learning FDB through notification"). Therefore, the mv88e6xxx driver must close this race condition by itself, by asking DSA to flush the switchdev workqueue of any FDB deletions in progress, prior to exiting a VLAN. Fixes: c9eb3e0f8701 ("net: dsa: Add support for learning FDB through notification") Reported-by: Rafael Richter <rafael.richter@gin.de> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-30devlink: Simplify devlink resources unregister callLeon Romanovsky
The devlink_resources_unregister() used second parameter as an entry point for the recursive removal of devlink resources. None of the callers outside of devlink core needed to use this field, so let's remove it. As part of this removal, the "struct devlink_resource" was moved from .h to .c file as it is not possible to use in any place in the code except devlink.c. Signed-off-by: Leon Romanovsky <leonro@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-21net: dsa: remove the "dsa_to_port in a loop" antipattern from the coreVladimir Oltean
Ever since Vivien's conversion of the ds->ports array into a dst->ports list, and the introduction of dsa_to_port, iterations through the ports of a switch became quadratic whenever dsa_to_port was needed. dsa_to_port can either be called directly, or indirectly through the dsa_is_{user,cpu,dsa,unused}_port helpers. Use the newly introduced dsa_switch_for_each_port() iteration macro that works with the iterator variable being a struct dsa_port *dp directly, and not an int i. It is an expensive variable to go from i to dp, but cheap to go from dp to i. This macro iterates through the entire ds->dst->ports list and filters by the ports belonging just to the switch provided as argument. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-15net: dsa: flush switchdev workqueue before tearing down CPU/DSA portsVladimir Oltean
Sometimes when unbinding the mv88e6xxx driver on Turris MOX, these error messages appear: mv88e6085 d0032004.mdio-mii:12: port 1 failed to delete be:79:b4:9e:9e:96 vid 1 from fdb: -2 mv88e6085 d0032004.mdio-mii:12: port 1 failed to delete be:79:b4:9e:9e:96 vid 0 from fdb: -2 mv88e6085 d0032004.mdio-mii:12: port 1 failed to delete d8:58:d7:00:ca:6d vid 100 from fdb: -2 mv88e6085 d0032004.mdio-mii:12: port 1 failed to delete d8:58:d7:00:ca:6d vid 1 from fdb: -2 mv88e6085 d0032004.mdio-mii:12: port 1 failed to delete d8:58:d7:00:ca:6d vid 0 from fdb: -2 (and similarly for other ports) What happens is that DSA has a policy "even if there are bugs, let's at least not leak memory" and dsa_port_teardown() clears the dp->fdbs and dp->mdbs lists, which are supposed to be empty. But deleting that cleanup code, the warnings go away. => the FDB and MDB lists (used for refcounting on shared ports, aka CPU and DSA ports) will eventually be empty, but are not empty by the time we tear down those ports. Aka we are deleting them too soon. The addresses that DSA complains about are host-trapped addresses: the local addresses of the ports, and the MAC address of the bridge device. The problem is that offloading those entries happens from a deferred work item scheduled by the SWITCHDEV_FDB_DEL_TO_DEVICE handler, and this races with the teardown of the CPU and DSA ports where the refcounting is kept. In fact, not only it races, but fundamentally speaking, if we iterate through the port list linearly, we might end up tearing down the shared ports even before we delete a DSA user port which has a bridge upper. So as it turns out, we need to first tear down the user ports (and the unused ones, for no better place of doing that), then the shared ports (the CPU and DSA ports). In between, we need to ensure that all work items scheduled by our switchdev handlers (which only run for user ports, hence the reason why we tear them down first) have finished. Fixes: 161ca59d39e9 ("net: dsa: reference count the MDB entries at the cross-chip notifier level") Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Link: https://lore.kernel.org/r/20210914134726.2305133-1-vladimir.oltean@nxp.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-08-02net: dsa: remove the struct packet_type argument from dsa_device_ops::rcv()Vladimir Oltean
No tagging driver uses this. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-01-29net: dsa: allow changing the tag protocol via the "tagging" device attributeVladimir Oltean
Currently DSA exposes the following sysfs: $ cat /sys/class/net/eno2/dsa/tagging ocelot which is a read-only device attribute, introduced in the kernel as commit 98cdb4807123 ("net: dsa: Expose tagging protocol to user-space"), and used by libpcap since its commit 993db3800d7d ("Add support for DSA link-layer types"). It would be nice if we could extend this device attribute by making it writable: $ echo ocelot-8021q > /sys/class/net/eno2/dsa/tagging This is useful with DSA switches that can make use of more than one tagging protocol. It may be useful in dsa_loop in the future too, to perform offline testing of various taggers, or for changing between dsa and edsa on Marvell switches, if that is desirable. In terms of implementation, drivers can support this feature by implementing .change_tag_protocol, which should always leave the switch in a consistent state: either with the new protocol if things went well, or with the old one if something failed. Teardown of the old protocol, if necessary, must be handled by the driver. Some things remain as before: - The .get_tag_protocol is currently only called at probe time, to load the initial tagging protocol driver. Nonetheless, new drivers should report the tagging protocol in current use now. - The driver should manage by itself the initial setup of tagging protocol, no later than the .setup() method, as well as destroying resources used by the last tagger in use, no earlier than the .teardown() method. For multi-switch DSA trees, error handling is a bit more complicated, since e.g. the 5th out of 7 switches may fail to change the tag protocol. When that happens, a revert to the original tag protocol is attempted, but that may fail too, leaving the tree in an inconsistent state despite each individual switch implementing .change_tag_protocol transactionally. Since the intersection between drivers that implement .change_tag_protocol and drivers that support D in DSA is currently the empty set, the possibility for this error to happen is ignored for now. Testing: $ insmod mscc_felix.ko [ 79.549784] mscc_felix 0000:00:00.5: Adding to iommu group 14 [ 79.565712] mscc_felix 0000:00:00.5: Failed to register DSA switch: -517 $ insmod tag_ocelot.ko $ rmmod mscc_felix.ko $ insmod mscc_felix.ko [ 97.261724] libphy: VSC9959 internal MDIO bus: probed [ 97.267363] mscc_felix 0000:00:00.5: Found PCS at internal MDIO address 0 [ 97.274998] mscc_felix 0000:00:00.5: Found PCS at internal MDIO address 1 [ 97.282561] mscc_felix 0000:00:00.5: Found PCS at internal MDIO address 2 [ 97.289700] mscc_felix 0000:00:00.5: Found PCS at internal MDIO address 3 [ 97.599163] mscc_felix 0000:00:00.5 swp0 (uninitialized): PHY [0000:00:00.3:10] driver [Microsemi GE VSC8514 SyncE] (irq=POLL) [ 97.862034] mscc_felix 0000:00:00.5 swp1 (uninitialized): PHY [0000:00:00.3:11] driver [Microsemi GE VSC8514 SyncE] (irq=POLL) [ 97.950731] mscc_felix 0000:00:00.5 swp0: configuring for inband/qsgmii link mode [ 97.964278] 8021q: adding VLAN 0 to HW filter on device swp0 [ 98.146161] mscc_felix 0000:00:00.5 swp2 (uninitialized): PHY [0000:00:00.3:12] driver [Microsemi GE VSC8514 SyncE] (irq=POLL) [ 98.238649] mscc_felix 0000:00:00.5 swp1: configuring for inband/qsgmii link mode [ 98.251845] 8021q: adding VLAN 0 to HW filter on device swp1 [ 98.433916] mscc_felix 0000:00:00.5 swp3 (uninitialized): PHY [0000:00:00.3:13] driver [Microsemi GE VSC8514 SyncE] (irq=POLL) [ 98.485542] mscc_felix 0000:00:00.5: configuring for fixed/internal link mode [ 98.503584] mscc_felix 0000:00:00.5: Link is Up - 2.5Gbps/Full - flow control rx/tx [ 98.527948] device eno2 entered promiscuous mode [ 98.544755] DSA: tree 0 setup $ ping 10.0.0.1 PING 10.0.0.1 (10.0.0.1): 56 data bytes 64 bytes from 10.0.0.1: seq=0 ttl=64 time=2.337 ms 64 bytes from 10.0.0.1: seq=1 ttl=64 time=0.754 ms ^C - 10.0.0.1 ping statistics - 2 packets transmitted, 2 packets received, 0% packet loss round-trip min/avg/max = 0.754/1.545/2.337 ms $ cat /sys/class/net/eno2/dsa/tagging ocelot $ cat ./test_ocelot_8021q.sh #!/bin/bash ip link set swp0 down ip link set swp1 down ip link set swp2 down ip link set swp3 down ip link set swp5 down ip link set eno2 down echo ocelot-8021q > /sys/class/net/eno2/dsa/tagging ip link set eno2 up ip link set swp0 up ip link set swp1 up ip link set swp2 up ip link set swp3 up ip link set swp5 up $ ./test_ocelot_8021q.sh ./test_ocelot_8021q.sh: line 9: echo: write error: Protocol not available $ rmmod tag_ocelot.ko rmmod: can't unload module 'tag_ocelot': Resource temporarily unavailable $ insmod tag_ocelot_8021q.ko $ ./test_ocelot_8021q.sh $ cat /sys/class/net/eno2/dsa/tagging ocelot-8021q $ rmmod tag_ocelot.ko $ rmmod tag_ocelot_8021q.ko rmmod: can't unload module 'tag_ocelot_8021q': Resource temporarily unavailable $ ping 10.0.0.1 PING 10.0.0.1 (10.0.0.1): 56 data bytes 64 bytes from 10.0.0.1: seq=0 ttl=64 time=0.953 ms 64 bytes from 10.0.0.1: seq=1 ttl=64 time=0.787 ms 64 bytes from 10.0.0.1: seq=2 ttl=64 time=0.771 ms $ rmmod mscc_felix.ko [ 645.544426] mscc_felix 0000:00:00.5: Link is Down [ 645.838608] DSA: tree 0 torn down $ rmmod tag_ocelot_8021q.ko Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-14net: dsa: tag_dsa: Support reception of packets from LAG devicesTobias Waldekranz
Packets ingressing on a LAG that egress on the CPU port, which are not classified as management, will have a FORWARD tag that does not contain the normal source device/port tuple. Instead the trunk bit will be set, and the port field holds the LAG id. Since the exact source port information is not available in the tag, frames are injected directly on the LAG interface and thus do never pass through any DSA port interface on ingress. Management frames (TO_CPU) are not affected and will pass through the DSA port interface as usual. Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Reviewed-by: Vladimir Oltean <olteanv@gmail.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-07net: dsa: remove the DSA specific notifiersVladimir Oltean
This effectively reverts commit 60724d4bae14 ("net: dsa: Add support for DSA specific notifiers"). The reason is that since commit 2f1e8ea726e9 ("net: dsa: link interfaces with the DSA master to get rid of lockdep warnings"), it appears that there is a generic way to achieve the same purpose. The only user thus far, the Broadcom SYSTEMPORT driver, was converted to use the generic notifiers. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Acked-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-09net: dsa: use net core stats64 handlingHeiner Kallweit
Use netdev->tstats instead of a member of dsa_slave_priv for storing a pointer to the per-cpu counters. This allows us to use core functionality for statistics handling. Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Tested-by: Vladimir Oltean <olteanv@gmail.com> Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-10-04net: dsa: Add devlink port regions support to DSAAndrew Lunn
Allow DSA drivers to make use of devlink port regions, via simple wrappers. Reviewed-by: Vladimir Oltean <olteanv@gmail.com> Tested-by: Vladimir Oltean <olteanv@gmail.com> Signed-off-by: Andrew Lunn <andrew@lunn.ch> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-10-02net: dsa: Call dsa_untag_bridge_pvid() from dsa_switch_rcv()Florian Fainelli
When a DSA switch driver needs to call dsa_untag_bridge_pvid(), it can set dsa_switch::untag_brige_pvid to indicate this is necessary. This is a pre-requisite to making sure that we are always calling dsa_untag_bridge_pvid() after eth_type_trans() has been called. Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-18net: dsa: Add devlink regions support to DSAAndrew Lunn
Allow DSA drivers to make use of devlink regions, via simple wrappers. Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-18net: dsa: Add helper to convert from devlink to dsAndrew Lunn
Given a devlink instance, return the dsa switch it is associated to. Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: David S. Miller <davem@davemloft.net>