linux.git/net/dsa, branch vsnprintf Linux kernel source tree net: dsa: restore dsa_software_vlan_untag() ability to operate on VLAN-untagged traffic 2024-12-19T03:22:36+00:00 Vladimir Oltean vladimir.oltean@nxp.com 2024-12-16T13:50:59+00:00 16f027cd40eeedd2325f7e720689462ca8d9d13e Robert Hodaszi reports that locally terminated traffic towards VLAN-unaware bridge ports is broken with ocelot-8021q. He is describing the same symptoms as for commit 1f9fc48fd302 ("net: dsa: sja1105: fix reception from VLAN-unaware bridges"). For context, the set merged as "VLAN fixes for Ocelot driver": https://lore.kernel.org/netdev/20240815000707.2006121-1-vladimir.oltean@nxp.com/ was developed in a slightly different form earlier this year, in January. Initially, the switch was unconditionally configured to set OCELOT_ES0_TAG when using ocelot-8021q, regardless of port operating mode. This led to the situation where VLAN-unaware bridge ports would always push their PVID - see ocelot_vlan_unaware_pvid() - a negligible value anyway - into RX packets. To strip this in software, we would have needed DSA to know what private VID the switch chose for VLAN-unaware bridge ports, and pushed into the packets. This was implemented downstream, and a remnant of it remains in the form of a comment mentioning ds->ops->get_private_vid(), as something which would maybe need to be considered in the future. However, for upstream, it was deemed inappropriate, because it would mean introducing yet another behavior for stripping VLAN tags from VLAN-unaware bridge ports, when one already existed (ds->untag_bridge_pvid). The latter has been marked as obsolete along with an explanation why it is logically broken, but still, it would have been confusing. So, for upstream, felix_update_tag_8021q_rx_rule() was developed, which essentially changed the state of affairs from "Felix with ocelot-8021q delivers all packets as VLAN-tagged towards the CPU" into "Felix with ocelot-8021q delivers all packets from VLAN-aware bridge ports towards the CPU". This was done on the premise that in VLAN-unaware mode, there's nothing useful in the VLAN tags, and we can avoid introducing ds->ops->get_private_vid() in the DSA receive path if we configure the switch to not push those VLAN tags into packets in the first place. Unfortunately, and this is when the trainwreck started, the selftests developed initially and posted with the series were not re-ran. dsa_software_vlan_untag() was initially written given the assumption that users of this feature would send _all_ traffic as VLAN-tagged. It was only partially adapted to the new scheme, by removing ds->ops->get_private_vid(), which also used to be necessary in standalone ports mode. Where the trainwreck became even worse is that I had a second opportunity to think about this, when the dsa_software_vlan_untag() logic change initially broke sja1105, in commit 1f9fc48fd302 ("net: dsa: sja1105: fix reception from VLAN-unaware bridges"). I did not connect the dots that it also breaks ocelot-8021q, for pretty much the same reason that not all received packets will be VLAN-tagged. To be compatible with the optimized Felix control path which runs felix_update_tag_8021q_rx_rule() to only push VLAN tags when useful (in VLAN-aware mode), we need to restore the old dsa_software_vlan_untag() logic. The blamed commit introduced the assumption that dsa_software_vlan_untag() will see only VLAN-tagged packets, assumption which is false. What corrupts RX traffic is the fact that we call skb_vlan_untag() on packets which are not VLAN-tagged in the first place. Fixes: 93e4649efa96 ("net: dsa: provide a software untagging function on RX for VLAN-aware bridges") Reported-by: Robert Hodaszi <robert.hodaszi@digi.com> Closes: https://lore.kernel.org/netdev/20241215163334.615427-1-robert.hodaszi@digi.com/ Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Link: https://patch.msgid.link/20241216135059.1258266-1-vladimir.oltean@nxp.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Robert Hodaszi reports that locally terminated traffic towards
VLAN-unaware bridge ports is broken with ocelot-8021q. He is describing
the same symptoms as for commit 1f9fc48fd302 ("net: dsa: sja1105: fix
reception from VLAN-unaware bridges").

For context, the set merged as "VLAN fixes for Ocelot driver":
https://lore.kernel.org/netdev/20240815000707.2006121-1-vladimir.oltean@nxp.com/

was developed in a slightly different form earlier this year, in January.
Initially, the switch was unconditionally configured to set OCELOT_ES0_TAG
when using ocelot-8021q, regardless of port operating mode.

This led to the situation where VLAN-unaware bridge ports would always
push their PVID - see ocelot_vlan_unaware_pvid() - a negligible value
anyway - into RX packets. To strip this in software, we would have needed
DSA to know what private VID the switch chose for VLAN-unaware bridge
ports, and pushed into the packets. This was implemented downstream, and
a remnant of it remains in the form of a comment mentioning
ds->ops->get_private_vid(), as something which would maybe need to be
considered in the future.

However, for upstream, it was deemed inappropriate, because it would
mean introducing yet another behavior for stripping VLAN tags from
VLAN-unaware bridge ports, when one already existed (ds->untag_bridge_pvid).
The latter has been marked as obsolete along with an explanation why it
is logically broken, but still, it would have been confusing.

So, for upstream, felix_update_tag_8021q_rx_rule() was developed, which
essentially changed the state of affairs from "Felix with ocelot-8021q
delivers all packets as VLAN-tagged towards the CPU" into "Felix with
ocelot-8021q delivers all packets from VLAN-aware bridge ports towards
the CPU". This was done on the premise that in VLAN-unaware mode,
there's nothing useful in the VLAN tags, and we can avoid introducing
ds->ops->get_private_vid() in the DSA receive path if we configure the
switch to not push those VLAN tags into packets in the first place.

Unfortunately, and this is when the trainwreck started, the selftests
developed initially and posted with the series were not re-ran.
dsa_software_vlan_untag() was initially written given the assumption
that users of this feature would send _all_ traffic as VLAN-tagged.
It was only partially adapted to the new scheme, by removing
ds->ops->get_private_vid(), which also used to be necessary in
standalone ports mode.

Where the trainwreck became even worse is that I had a second opportunity
to think about this, when the dsa_software_vlan_untag() logic change
initially broke sja1105, in commit 1f9fc48fd302 ("net: dsa: sja1105: fix
reception from VLAN-unaware bridges"). I did not connect the dots that
it also breaks ocelot-8021q, for pretty much the same reason that not
all received packets will be VLAN-tagged.

To be compatible with the optimized Felix control path which runs
felix_update_tag_8021q_rx_rule() to only push VLAN tags when useful (in
VLAN-aware mode), we need to restore the old dsa_software_vlan_untag()
logic. The blamed commit introduced the assumption that
dsa_software_vlan_untag() will see only VLAN-tagged packets, assumption
which is false. What corrupts RX traffic is the fact that we call
skb_vlan_untag() on packets which are not VLAN-tagged in the first
place.

Fixes: 93e4649efa96 ("net: dsa: provide a software untagging function on RX for VLAN-aware bridges")
Reported-by: Robert Hodaszi <robert.hodaszi@digi.com>
Closes: https://lore.kernel.org/netdev/20241215163334.615427-1-robert.hodaszi@digi.com/
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://patch.msgid.link/20241216135059.1258266-1-vladimir.oltean@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
net: dsa: tag_ocelot_8021q: fix broken reception 2024-12-12T15:10:27+00:00 Robert Hodaszi robert.hodaszi@digi.com 2024-12-11T14:47:41+00:00 36ff681d2283410742489ce77e7b01419eccf58c The blamed commit changed the dsa_8021q_rcv() calling convention to accept pre-populated source_port and switch_id arguments. If those are not available, as in the case of tag_ocelot_8021q, the arguments must be pre-initialized with -1. Due to the bug of passing uninitialized arguments in tag_ocelot_8021q, dsa_8021q_rcv() does not detect that it needs to populate the source_port and switch_id, and this makes dsa_conduit_find_user() fail, which leads to packet loss on reception. Fixes: dcfe7673787b ("net: dsa: tag_sja1105: absorb logic for not overwriting precise info into dsa_8021q_rcv()") Signed-off-by: Robert Hodaszi <robert.hodaszi@digi.com> Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com> Link: https://patch.msgid.link/20241211144741.1415758-1-robert.hodaszi@digi.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
The blamed commit changed the dsa_8021q_rcv() calling convention to
accept pre-populated source_port and switch_id arguments. If those are
not available, as in the case of tag_ocelot_8021q, the arguments must be
pre-initialized with -1.

Due to the bug of passing uninitialized arguments in tag_ocelot_8021q,
dsa_8021q_rcv() does not detect that it needs to populate the
source_port and switch_id, and this makes dsa_conduit_find_user() fail,
which leads to packet loss on reception.

Fixes: dcfe7673787b ("net: dsa: tag_sja1105: absorb logic for not overwriting precise info into dsa_8021q_rcv()")
Signed-off-by: Robert Hodaszi <robert.hodaszi@digi.com>
Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://patch.msgid.link/20241211144741.1415758-1-robert.hodaszi@digi.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
net: dsa: use ethtool string helpers 2024-11-03T18:36:34+00:00 Rosen Penev rosenp@gmail.com 2024-10-28T04:48:28+00:00 f12b363887c706c40611fba645265527a8415832 These are the preferred way to copy ethtool strings. Avoids incrementing pointers all over the place. Signed-off-by: Rosen Penev <rosenp@gmail.com> (for hellcreek driver) Reviewed-by: Kurt Kanzenbach <kurt@linutronix.de> Link: https://patch.msgid.link/20241028044828.1639668-1-rosenp@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
These are the preferred way to copy ethtool strings.

Avoids incrementing pointers all over the place.

Signed-off-by: Rosen Penev <rosenp@gmail.com>
(for hellcreek driver)
Reviewed-by: Kurt Kanzenbach <kurt@linutronix.de>
Link: https://patch.msgid.link/20241028044828.1639668-1-rosenp@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
net: dsa: allow matchall mirroring rules towards the CPU 2024-10-31T00:33:54+00:00 Vladimir Oltean vladimir.oltean@nxp.com 2024-10-23T13:52:50+00:00 3535d70df9c80b382a202baa430aa8fbb2433bfa If the CPU bandwidth capacity permits, it may be useful to mirror the entire ingress of a user port to software. This is in fact possible to express even if there is no net_device representation for the CPU port. In fact, that approach was already exhausted and that representation wouldn't have even helped [1]. The idea behind implementing this is that currently, we refuse to offload any mirroring towards a non-DSA target net_device. But if we acknowledge the fact that to reach any foreign net_device, the switch must send the packet to the CPU anyway, then we can simply offload just that part, and let the software do the rest. There is only one condition we need to uphold: the filter needs to be present in the software data path as well (no skip_sw). There are 2 actions to consider: FLOW_ACTION_MIRRED (redirect to egress of target interface) and FLOW_ACTION_MIRRED_INGRESS (redirect to ingress of target interface). We don't have the ability/API to offload FLOW_ACTION_MIRRED_INGRESS when the target port is also a DSA user port, but we could also permit that through mirred to the CPU + software. Example: $ ip link add dummy0 type dummy; ip link set dummy0 up $ tc qdisc add dev swp0 clsact $ tc filter add dev swp0 ingress matchall action mirred ingress mirror dev dummy0 Any DSA driver with a ds->ops->port_mirror_add() implementation can now make use of this with no additional change. [1] https://lore.kernel.org/netdev/20191002233750.13566-1-olteanv@gmail.com/ Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Link: https://patch.msgid.link/20241023135251.1752488-6-vladimir.oltean@nxp.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
If the CPU bandwidth capacity permits, it may be useful to mirror the
entire ingress of a user port to software.

This is in fact possible to express even if there is no net_device
representation for the CPU port. In fact, that approach was already
exhausted and that representation wouldn't have even helped [1].

The idea behind implementing this is that currently, we refuse to
offload any mirroring towards a non-DSA target net_device. But if we
acknowledge the fact that to reach any foreign net_device, the switch
must send the packet to the CPU anyway, then we can simply offload just
that part, and let the software do the rest. There is only one condition
we need to uphold: the filter needs to be present in the software data
path as well (no skip_sw).

There are 2 actions to consider: FLOW_ACTION_MIRRED (redirect to egress
of target interface) and FLOW_ACTION_MIRRED_INGRESS (redirect to ingress
of target interface). We don't have the ability/API to offload
FLOW_ACTION_MIRRED_INGRESS when the target port is also a DSA user port,
but we could also permit that through mirred to the CPU + software.

Example:

$ ip link add dummy0 type dummy; ip link set dummy0 up
$ tc qdisc add dev swp0 clsact
$ tc filter add dev swp0 ingress matchall action mirred ingress mirror dev dummy0

Any DSA driver with a ds->ops->port_mirror_add() implementation can now
make use of this with no additional change.

[1] https://lore.kernel.org/netdev/20191002233750.13566-1-olteanv@gmail.com/
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://patch.msgid.link/20241023135251.1752488-6-vladimir.oltean@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
net: dsa: add more extack messages in dsa_user_add_cls_matchall_mirred() 2024-10-31T00:33:54+00:00 Vladimir Oltean vladimir.oltean@nxp.com 2024-10-23T13:52:49+00:00 4cc4394a897eae27405396d1d756a9f75a3addc3 Do not leave -EOPNOTSUPP errors without an explanation. It is confusing for the user to figure out what is wrong otherwise. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Link: https://patch.msgid.link/20241023135251.1752488-5-vladimir.oltean@nxp.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Do not leave -EOPNOTSUPP errors without an explanation. It is confusing
for the user to figure out what is wrong otherwise.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://patch.msgid.link/20241023135251.1752488-5-vladimir.oltean@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
net: dsa: use "extack" as argument to flow_action_basic_hw_stats_check() 2024-10-31T00:33:54+00:00 Vladimir Oltean vladimir.oltean@nxp.com 2024-10-23T13:52:48+00:00 c11ace14d9db3a2e2e7b473ff8f79c7b1c998191 We already have an "extack" stack variable in dsa_user_add_cls_matchall_police() and dsa_user_add_cls_matchall_mirred(), there is no need to retrieve it again from cls->common.extack. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Link: https://patch.msgid.link/20241023135251.1752488-4-vladimir.oltean@nxp.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
We already have an "extack" stack variable in
dsa_user_add_cls_matchall_police() and
dsa_user_add_cls_matchall_mirred(), there is no need to retrieve
it again from cls->common.extack.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://patch.msgid.link/20241023135251.1752488-4-vladimir.oltean@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
net: dsa: clean up dsa_user_add_cls_matchall() 2024-10-31T00:33:53+00:00 Vladimir Oltean vladimir.oltean@nxp.com 2024-10-23T13:52:47+00:00 a0af7162ccb501a22ac448ad94dad81757743725 The body is a bit hard to read, hard to extend, and has duplicated conditions. Clean up the "if (many conditions) else if (many conditions, some of them repeated)" pattern by: - Moving the repeated conditions out - Replacing the repeated tests for the same variable with a switch/case - Moving the protocol check inside the dsa_user_add_cls_matchall_mirred() function call. This is pure refactoring, no logic has been changed, though some tests were reordered. The order does not matter - they are independent things to be tested for. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Link: https://patch.msgid.link/20241023135251.1752488-3-vladimir.oltean@nxp.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
The body is a bit hard to read, hard to extend, and has duplicated
conditions.

Clean up the "if (many conditions) else if (many conditions, some
of them repeated)" pattern by:

- Moving the repeated conditions out
- Replacing the repeated tests for the same variable with a switch/case
- Moving the protocol check inside the dsa_user_add_cls_matchall_mirred()
  function call.

This is pure refactoring, no logic has been changed, though some tests
were reordered. The order does not matter - they are independent things
to be tested for.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://patch.msgid.link/20241023135251.1752488-3-vladimir.oltean@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
net: dsa: replace devlink resource registration calls by devl_ variants 2024-10-29T23:52:57+00:00 Przemek Kitszel przemyslaw.kitszel@intel.com 2024-10-23T13:09:05+00:00 d5020cb41e3c19196fe6f180950867ab7510d398 Replace devlink_resource_register(), devlink_resource_occ_get_register(), and devlink_resource_occ_get_unregister() calls by respective devl_* variants. Mentioned functions have no direct users in any drivers, and are going to be removed in subsequent patches. Reviewed-by: Wojciech Drewek <wojciech.drewek@intel.com> Reviewed-by: Jiri Pirko <jiri@nvidia.com> Reviewed-by: Joe Damato <jdamato@fastly.com> Signed-off-by: Przemek Kitszel <przemyslaw.kitszel@intel.com> Link: https://patch.msgid.link/20241023131248.27192-6-przemyslaw.kitszel@intel.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Replace devlink_resource_register(), devlink_resource_occ_get_register(),
and devlink_resource_occ_get_unregister() calls by respective devl_*
variants. Mentioned functions have no direct users in any drivers, and are
going to be removed in subsequent patches.

Reviewed-by: Wojciech Drewek <wojciech.drewek@intel.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Reviewed-by: Joe Damato <jdamato@fastly.com>
Signed-off-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
Link: https://patch.msgid.link/20241023131248.27192-6-przemyslaw.kitszel@intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
netpoll: remove ndo_netpoll_setup() second argument 2024-10-23T11:31:32+00:00 Eric Dumazet edumazet@google.com 2024-10-18T05:21:08+00:00 e44ef3f66c5472c2cbc6957c684d7279c26b0db1 npinfo is not used in any of the ndo_netpoll_setup() methods. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://patch.msgid.link/20241018052108.2610827-1-edumazet@google.com Signed-off-by: Paolo Abeni <pabeni@redhat.com> 
npinfo is not used in any of the ndo_netpoll_setup() methods.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20241018052108.2610827-1-edumazet@google.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
net: dsa: remove dsa_port_phylink_mac_select_pcs() 2024-10-17T23:15:14+00:00 Russell King (Oracle) rmk+kernel@armlinux.org.uk 2024-10-16T09:58:24+00:00 ecb595ebba0e72fd2137260281b3c773171c8317 There is no longer any reason to implement the mac_select_pcs() callback in DSA. Returning ERR_PTR(-EOPNOTSUPP) is functionally equivalent to not providing the function. Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Signed-off-by: Andrew Lunn <andrew@lunn.ch> 
There is no longer any reason to implement the mac_select_pcs()
callback in DSA. Returning ERR_PTR(-EOPNOTSUPP) is functionally
equivalent to not providing the function.

Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: Andrew Lunn <andrew@lunn.ch>