At present, when a PTP packet which requires TX timestamping gets
dropped under congestion by the switch, things go downhill very fast.
The driver keeps a clone of that skb in a queue of packets awaiting TX
timestamp interrupts, but interrupts will never be raised for the
dropped packets.

Moreover, matching timestamped packets to timestamps is done by a 2-bit
timestamp ID, and this can wrap around and we can match on the wrong skb.

Since with the default NPI-based tagging protocol, we get no notification
about packet drops, the best we can do is eventually recover from the
drop of a PTP frame: its skb will be dead memory until another skb which
was assigned the same timestamp ID happens to find it.

However, with the ocelot-8021q tagger which injects packets using the
manual register interface, it appears that we can check for more
information, such as:

- whether the input queue has reached the high watermark or not
- whether the injection group's FIFO can accept additional data or not

so we know that a PTP frame is likely to get dropped before actually
sending it, and drop it ourselves (because DSA uses NETIF_F_LLTX, so it
can't return NETDEV_TX_BUSY to ask the qdisc to requeue the packet).

But when we do that, we can also remove the skb from the timestamping
queue, because there surely won't be any timestamp that matches it.

Fixes: 0a6f17c6 ("net: dsa: tag_ocelot_8021q: add support for PTP timestamping")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Michael reported that when using the "ocelot-8021q" tagging protocol,
the switch driver module must be manually loaded before the tagging
protocol can be loaded/is available.

This appears to be the same problem described here:
https://lore.kernel.org/netdev/20210908220834.d7gmtnwrorhharna@skbuf/
where due to the fact that DSA tagging protocols make use of symbols
exported by the switch drivers, circular dependencies appear and this
breaks module autoloading.

The ocelot_8021q driver needs the ocelot_can_inject() and
ocelot_port_inject_frame() functions from the switch library. Previously
the wrong approach was taken to solve that dependency: shims were
provided for the case where the ocelot switch library was compiled out,
but that turns out to be insufficient, because the dependency when the
switch lib _is_ compiled is problematic too.

We cannot declare ocelot_can_inject() and ocelot_port_inject_frame() as
static inline functions, because these access I/O functions like
__ocelot_write_ix() which is called by ocelot_write_rix(). Making those
static inline basically means exposing the whole guts of the ocelot
switch library, not ideal...

We already have one tagging protocol driver which calls into the switch
driver during xmit but not using any exported symbol: sja1105_defer_xmit.
We can do the same thing here: create a kthread worker and one work item
per skb, and let the switch driver itself do the register accesses to
send the skb, and then consume it.

Fixes: 0a6f17c6 ("net: dsa: tag_ocelot_8021q: add support for PTP timestamping")
Reported-by: Michael Walle <michael@walle.cc>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

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 40d3f295 ("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: 39e5308b ("net: mscc: ocelot: support PTP Sync one-step timestamping")
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>

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: 4e3b0468 ("net: mscc: PTP Hardware Clock (PHC) support")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

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: 4e3b0468 ("net: mscc: PTP Hardware Clock (PHC) support")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

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: 4e3b0468 ("net: mscc: PTP Hardware Clock (PHC) support")
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>

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: 4e3b0468 ("net: mscc: PTP Hardware Clock (PHC) support")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

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: 4e3b0468 ("net: mscc: PTP Hardware Clock (PHC) support")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Vladimir Oltean says:

====================
Fix circular dependency between sja1105 and tag_sja1105

As discussed here:
https://lore.kernel.org/netdev/20210908220834.d7gmtnwrorhharna@skbuf/
DSA tagging protocols cannot use symbols exported by switch drivers.

Eliminate the two instances of that from tag_sja1105, and that allows us
to have a working setup with modules again.
====================

Re-applying to net, this was mistakenly applied to net-next,
see first Link.

Link: https://lore.kernel.org/r/20211012114044.2526146-1-vladimir.oltean@nxp.com/
Link: https://lore.kernel.org/r/20210922143726.2431036-1-vladimir.oltean@nxp.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

It's nice to be able to test a tagging protocol with dsa_loop, but not
at the cost of losing the ability of building the tagging protocol and
switch driver as modules, because as things stand, there is a circular
dependency between the two. Tagging protocol drivers cannot depend on
switch drivers, that is a hard fact.

The reasoning behind the blamed patch was that accessing dp->priv should
first make sure that the structure behind that pointer is what we really
think it is.

Currently the "sja1105" and "sja1110" tagging protocols only operate
with the sja1105 switch driver, just like any other tagging protocol and
switch combination. The only way to mix and match them is by modifying
the code, and this applies to dsa_loop as well (by default that uses
DSA_TAG_PROTO_NONE). So while in principle there is an issue, in
practice there isn't one.

Until we extend dsa_loop to allow user space configuration, treat the
problem as a non-issue and just say that DSA ports found by tag_sja1105
are always sja1105 ports, which is in fact true. But keep the
dsa_port_is_sja1105 function so that it's easy to patch it during
testing, and rely on dead code elimination.

Fixes: 994d2cbb ("net: dsa: tag_sja1105: be dsa_loop-safe")
Link: https://lore.kernel.org/netdev/20210908220834.d7gmtnwrorhharna@skbuf/Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

The problem is that DSA tagging protocols really must not depend on the
switch driver, because this creates a circular dependency at insmod
time, and the switch driver will effectively not load when the tagging
protocol driver is missing.

The code was structured in the way it was for a reason, though. The DSA
driver-facing API for PTP timestamping relies on the assumption that
two-step TX timestamps are provided by the hardware in an out-of-band
manner, typically by raising an interrupt and making that timestamp
available inside some sort of FIFO which is to be accessed over
SPI/MDIO/etc.

So the API puts .port_txtstamp into dsa_switch_ops, because it is
expected that the switch driver needs to save some state (like put the
skb into a queue until its TX timestamp arrives).

On SJA1110, TX timestamps are provided by the switch as Ethernet
packets, so this makes them be received and processed by the tagging
protocol driver. This in itself is great, because the timestamps are
full 64-bit and do not require reconstruction, and since Ethernet is the
fastest I/O method available to/from the switch, PTP timestamps arrive
very quickly, no matter how bottlenecked the SPI connection is, because
SPI interaction is not needed at all.

DSA's code structure and strict isolation between the tagging protocol
driver and the switch driver break the natural code organization.

When the tagging protocol driver receives a packet which is classified
as a metadata packet containing timestamps, it passes those timestamps
one by one to the switch driver, which then proceeds to compare them
based on the recorded timestamp ID that was generated in .port_txtstamp.

The communication between the tagging protocol and the switch driver is
done through a method exported by the switch driver, sja1110_process_meta_tstamp.
To satisfy build requirements, we force a dependency to build the
tagging protocol driver as a module when the switch driver is a module.
However, as explained in the first paragraph, that causes the circular
dependency.

To solve this, move the skb queue from struct sja1105_private :: struct
sja1105_ptp_data to struct sja1105_private :: struct sja1105_tagger_data.
The latter is a data structure for which hacks have already been put
into place to be able to create persistent storage per switch that is
accessible from the tagging protocol driver (see sja1105_setup_ports).

With the skb queue directly accessible from the tagging protocol driver,
we can now move sja1110_process_meta_tstamp into the tagging driver
itself, and avoid exporting a symbol.

Fixes: 566b18c8 ("net: dsa: sja1105: implement TX timestamping for SJA1110")
Link: https://lore.kernel.org/netdev/20210908220834.d7gmtnwrorhharna@skbuf/Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Flip the sign of a return value check, thereby suppressing the following
spurious error:

  port 2 failed to notify DSA_NOTIFIER_BRIDGE_LEAVE: -EOPNOTSUPP

... which is emitted when removing an unoffloaded DSA switch port from a
bridge.

Fixes: d371b7c9 ("net: dsa: Unset vlan_filtering when ports leave the bridge")
Signed-off-by: Alvin Šipraga <alsi@bang-olufsen.dk>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Link: https://lore.kernel.org/r/20211012112730.3429157-1-alvin@pqrs.dkSigned-off-by: Jakub Kicinski <kuba@kernel.org>

In commit 74fc4f82 ("net: Fix offloading indirect devices dependency
on qdisc order creation"), it adds a process to trigger the callback to
setup the bo callback when the driver regists a callback.

In our current implement, we are not ready to run the callback when nfp
call the function flow_indr_dev_register, then there will be error
message as:

kernel: Oops: 0000 [#1] SMP PTI
kernel: CPU: 0 PID: 14119 Comm: kworker/0:0 Tainted: G
kernel: Workqueue: events work_for_cpu_fn
kernel: RIP: 0010:nfp_flower_indr_setup_tc_cb+0x258/0x410
kernel: RSP: 0018:ffffbc1e02c57bf8 EFLAGS: 00010286
kernel: RAX: 0000000000000000 RBX: ffff9c761fabc000 RCX: 0000000000000001
kernel: RDX: 0000000000000001 RSI: fffffffffffffff0 RDI: ffffffffc0be9ef1
kernel: RBP: ffffbc1e02c57c58 R08: ffffffffc08f33aa R09: ffff9c6db7478800
kernel: R10: 0000009c003f6e00 R11: ffffbc1e02800000 R12: ffffbc1e000d9000
kernel: R13: ffffbc1e000db428 R14: ffff9c6db7478800 R15: ffff9c761e884e80
kernel: CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
kernel: CR2: fffffffffffffff0 CR3: 00000009e260a004 CR4: 00000000007706f0
kernel: DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
kernel: DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
kernel: PKRU: 55555554
kernel: Call Trace:
kernel: ? flow_indr_dev_register+0xab/0x210
kernel: ? __cond_resched+0x15/0x30
kernel: ? kmem_cache_alloc_trace+0x44/0x4b0
kernel: ? nfp_flower_setup_tc+0x1d0/0x1d0 [nfp]
kernel: flow_indr_dev_register+0x158/0x210
kernel: ? tcf_block_unbind+0xe0/0xe0
kernel: nfp_flower_init+0x40b/0x650 [nfp]
kernel: nfp_net_pci_probe+0x25f/0x960 [nfp]
kernel: ? nfp_rtsym_read_le+0x76/0x130 [nfp]
kernel: nfp_pci_probe+0x6a9/0x820 [nfp]
kernel: local_pci_probe+0x45/0x80

So we need to call flow_indr_dev_register in app start process instead of
init stage.

Fixes: 74fc4f82 ("net: Fix offloading indirect devices dependency on qdisc order creation")
Signed-off-by: Baowen Zheng <baowen.zheng@corigine.com>
Signed-off-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: Louis Peens <louis.peens@corigine.com>
Link: https://lore.kernel.org/r/20211012124850.13025-1-louis.peens@corigine.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Commit 4dd0d5c3 ("ice: add lock around Tx timestamp tracker flush")
added a lock around the Tx timestamp tracker flow which is used to
cleanup any left over SKBs and prepare for device removal.

This lock is problematic because it is being held around a call to
ice_clear_phy_tstamp. The clear function takes a mutex to send a PHY
write command to firmware. This could lead to a deadlock if the mutex
actually sleeps, and causes the following warning on a kernel with
preemption debugging enabled:

[  715.419426] BUG: sleeping function called from invalid context at kernel/locking/mutex.c:573
[  715.427900] in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 3100, name: rmmod
[  715.435652] INFO: lockdep is turned off.
[  715.439591] Preemption disabled at:
[  715.439594] [<0000000000000000>] 0x0
[  715.446678] CPU: 52 PID: 3100 Comm: rmmod Tainted: G        W  OE     5.15.0-rc4+ #42 bdd7ec3018e725f159ca0d372ce8c2c0e784891c
[  715.458058] Hardware name: Intel Corporation S2600STQ/S2600STQ, BIOS SE5C620.86B.02.01.0010.010620200716 01/06/2020
[  715.468483] Call Trace:
[  715.470940]  dump_stack_lvl+0x6a/0x9a
[  715.474613]  ___might_sleep.cold+0x224/0x26a
[  715.478895]  __mutex_lock+0xb3/0x1440
[  715.482569]  ? stack_depot_save+0x378/0x500
[  715.486763]  ? ice_sq_send_cmd+0x78/0x14c0 [ice 9a7e1ec00971c89ecd3fe0d4dc7da2b3786a421d]
[  715.494979]  ? kfree+0xc1/0x520
[  715.498128]  ? mutex_lock_io_nested+0x12a0/0x12a0
[  715.502837]  ? kasan_set_free_info+0x20/0x30
[  715.507110]  ? __kasan_slab_free+0x10b/0x140
[  715.511385]  ? slab_free_freelist_hook+0xc7/0x220
[  715.516092]  ? kfree+0xc1/0x520
[  715.519235]  ? ice_deinit_lag+0x16c/0x220 [ice 9a7e1ec00971c89ecd3fe0d4dc7da2b3786a421d]
[  715.527359]  ? ice_remove+0x1cf/0x6a0 [ice 9a7e1ec00971c89ecd3fe0d4dc7da2b3786a421d]
[  715.535133]  ? pci_device_remove+0xab/0x1d0
[  715.539318]  ? __device_release_driver+0x35b/0x690
[  715.544110]  ? driver_detach+0x214/0x2f0
[  715.548035]  ? bus_remove_driver+0x11d/0x2f0
[  715.552309]  ? pci_unregister_driver+0x26/0x250
[  715.556840]  ? ice_module_exit+0xc/0x2f [ice 9a7e1ec00971c89ecd3fe0d4dc7da2b3786a421d]
[  715.564799]  ? __do_sys_delete_module.constprop.0+0x2d8/0x4e0
[  715.570554]  ? do_syscall_64+0x3b/0x90
[  715.574303]  ? entry_SYSCALL_64_after_hwframe+0x44/0xae
[  715.579529]  ? start_flush_work+0x542/0x8f0
[  715.583719]  ? ice_sq_send_cmd+0x78/0x14c0 [ice 9a7e1ec00971c89ecd3fe0d4dc7da2b3786a421d]
[  715.591923]  ice_sq_send_cmd+0x78/0x14c0 [ice 9a7e1ec00971c89ecd3fe0d4dc7da2b3786a421d]
[  715.599960]  ? wait_for_completion_io+0x250/0x250
[  715.604662]  ? lock_acquire+0x196/0x200
[  715.608504]  ? do_raw_spin_trylock+0xa5/0x160
[  715.612864]  ice_sbq_rw_reg+0x1e6/0x2f0 [ice 9a7e1ec00971c89ecd3fe0d4dc7da2b3786a421d]
[  715.620813]  ? ice_reset+0x130/0x130 [ice 9a7e1ec00971c89ecd3fe0d4dc7da2b3786a421d]
[  715.628497]  ? __debug_check_no_obj_freed+0x1e8/0x3c0
[  715.633550]  ? trace_hardirqs_on+0x1c/0x130
[  715.637748]  ice_write_phy_reg_e810+0x70/0xf0 [ice 9a7e1ec00971c89ecd3fe0d4dc7da2b3786a421d]
[  715.646220]  ? do_raw_spin_trylock+0xa5/0x160
[  715.650581]  ? ice_ptp_release+0x910/0x910 [ice 9a7e1ec00971c89ecd3fe0d4dc7da2b3786a421d]
[  715.658797]  ? ice_ptp_release+0x255/0x910 [ice 9a7e1ec00971c89ecd3fe0d4dc7da2b3786a421d]
[  715.667013]  ice_clear_phy_tstamp+0x2c/0x110 [ice 9a7e1ec00971c89ecd3fe0d4dc7da2b3786a421d]
[  715.675403]  ice_ptp_release+0x408/0x910 [ice 9a7e1ec00971c89ecd3fe0d4dc7da2b3786a421d]
[  715.683440]  ice_remove+0x560/0x6a0 [ice 9a7e1ec00971c89ecd3fe0d4dc7da2b3786a421d]
[  715.691037]  ? _raw_spin_unlock_irqrestore+0x46/0x73
[  715.696005]  pci_device_remove+0xab/0x1d0
[  715.700018]  __device_release_driver+0x35b/0x690
[  715.704637]  driver_detach+0x214/0x2f0
[  715.708389]  bus_remove_driver+0x11d/0x2f0
[  715.712489]  pci_unregister_driver+0x26/0x250
[  715.716857]  ice_module_exit+0xc/0x2f [ice 9a7e1ec00971c89ecd3fe0d4dc7da2b3786a421d]
[  715.724637]  __do_sys_delete_module.constprop.0+0x2d8/0x4e0
[  715.730210]  ? free_module+0x6d0/0x6d0
[  715.733963]  ? task_work_run+0xe1/0x170
[  715.737803]  ? exit_to_user_mode_loop+0x17f/0x1d0
[  715.742509]  ? rcu_read_lock_sched_held+0x12/0x80
[  715.747215]  ? trace_hardirqs_on+0x1c/0x130
[  715.751401]  do_syscall_64+0x3b/0x90
[  715.754981]  entry_SYSCALL_64_after_hwframe+0x44/0xae
[  715.760033] RIP: 0033:0x7f4dfe59000b
[  715.763612] Code: 73 01 c3 48 8b 0d 6d 1e 0c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa b8 b0 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 3d 1e 0c 00 f7 d8 64 89 01 48
[  715.782357] RSP: 002b:00007ffe8c891708 EFLAGS: 00000206 ORIG_RAX: 00000000000000b0
[  715.789923] RAX: ffffffffffffffda RBX: 00005558a20468b0 RCX: 00007f4dfe59000b
[  715.797054] RDX: 000000000000000a RSI: 0000000000000800 RDI: 00005558a2046918
[  715.804189] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
[  715.811319] R10: 00007f4dfe603ac0 R11: 0000000000000206 R12: 00007ffe8c891940
[  715.818455] R13: 00007ffe8c8920a3 R14: 00005558a20462a0 R15: 00005558a20468b0

Notice that this is the only case where we use the lock in this way. In
the cleanup kthread and work kthread the lock is only taken around the
bit accesses. This was done intentionally to avoid this kind of issue.
The way the lock is used, we only protect ordering of bit sets vs bit
clears. The Tx writers in the hot path don't need to be protected
against the entire kthread loop. The Tx queues threads only need to
ensure that they do not re-use an index that is currently in use. The
cleanup loop does not need to block all new set bits, since it will
re-queue itself if new timestamps are present.

Fix the tracker flow so that it uses the same flow as the standard
cleanup thread. In addition, ensure the in_use bitmap actually gets
cleared properly.

This fixes the warning and also avoids the potential deadlock that might
have occurred otherwise.

Fixes: 4dd0d5c3 ("ice: add lock around Tx timestamp tracker flush")
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Justin Iurman says:

====================
Correct the IOAM behavior for undefined trace type bits

(@Jakub @David: there will be a conflict for #2 when merging net->net-next, due
to commit [1]. The conflict is only 5-10 lines for #2 (#1 should be fine) inside
the file tools/testing/selftests/net/ioam6.sh, so quite short though possibly
ugly. Sorry for that, I didn't expect to post this one... Had I known, I'd have
made the opposite.)

Modify both the input and output behaviors regarding the trace type when one of
the undefined bits is set. The goal is to keep the interoperability when new
fields (aka new bits inside the range 12-21) will be defined.

The draft [2] says the following:
---------------------------------------------------------------
"Bit 12-21  Undefined.  These values are available for future
       assignment in the IOAM Trace-Type Registry (Section 8.2).
       Every future node data field corresponding to one of
       these bits MUST be 4-octets long.  An IOAM encapsulating
       node MUST set the value of each undefined bit to 0.  If
       an IOAM transit node receives a packet with one or more
       of these bits set to 1, it MUST either:

       1.  Add corresponding node data filled with the reserved
           value 0xFFFFFFFF, after the node data fields for the
           IOAM-Trace-Type bits defined above, such that the
           total node data added by this node in units of
           4-octets is equal to NodeLen, or

       2.  Not add any node data fields to the packet, even for
           the IOAM-Trace-Type bits defined above."
---------------------------------------------------------------

The output behavior has been modified to respect the fact that "an IOAM encap
node MUST set the value of each undefined bit to 0" (i.e., undefined bits can't
be set anymore).

As for the input behavior, current implementation is based on the second choice
(i.e., "not add any data fields to the packet [...]"). With this solution, any
interoperability is lost (i.e., if a new bit is defined, then an "old" kernel
implementation wouldn't fill IOAM data when such new bit is set inside the trace
type).

The input behavior is therefore relaxed and these undefined bits are now allowed
to be set. It is only possible thanks to the sentence "every future node data
field corresponding to one of these bits MUST be 4-octets long". Indeed, the
default empty value (the one for 4-octet fields) is inserted whenever an
undefined bit is set.

  [1] cfbe9b00
  [2] https://datatracker.ietf.org/doc/html/draft-ietf-ippm-ioam-data#section-5.4.1
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

The output behavior for undefined bits is now directly tested inside the bash
script. Trying to set an undefined bit should be refused.

The input behavior for undefined bits has been removed due to the fact that we
would need another sender allowed to set undefined bits.
Signed-off-by: Justin Iurman <justin.iurman@uliege.be>
Signed-off-by: David S. Miller <davem@davemloft.net>

The check for undefined bits in the trace type is moved from the input side to
the output side, while the input side is relaxed and now inserts default empty
values when an undefined bit is set.
Signed-off-by: Justin Iurman <justin.iurman@uliege.be>
Signed-off-by: David S. Miller <davem@davemloft.net>

When the ksz module is installed and removed using rmmod, kernel crashes
with null pointer dereferrence error. During rmmod, ksz_switch_remove
function tries to cancel the mib_read_workqueue using
cancel_delayed_work_sync routine and unregister switch from dsa.

During dsa_unregister_switch it calls ksz_mac_link_down, which in turn
reschedules the workqueue since mib_interval is non-zero.
Due to which queue executed after mib_interval and it tries to access
dp->slave. But the slave is unregistered in the ksz_switch_remove
function. Hence kernel crashes.

To avoid this crash, before canceling the workqueue, resetted the
mib_interval to 0.

v1 -> v2:
-Removed the if condition in ksz_mib_read_work

Fixes: 469b390e ("net: dsa: microchip: use delayed_work instead of timer + work")
Signed-off-by: Arun Ramadoss <arun.ramadoss@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Fix the following build/link errors by adding a dependency on
CRYPTO, CRYPTO_HASH, CRYPTO_SHA256 and CRC32:

  ld: drivers/net/usb/r8152.o: in function `rtl8152_fw_verify_checksum':
  r8152.c:(.text+0x2b2a): undefined reference to `crypto_alloc_shash'
  ld: r8152.c:(.text+0x2bed): undefined reference to `crypto_shash_digest'
  ld: r8152.c:(.text+0x2c50): undefined reference to `crypto_destroy_tfm'
  ld: drivers/net/usb/r8152.o: in function `_rtl8152_set_rx_mode':
  r8152.c:(.text+0xdcb0): undefined reference to `crc32_le'

Fixes: 9370f2d0 ("r8152: support request_firmware for RTL8153")
Fixes: ac718b69 ("net/usb: new driver for RTL8152")
Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

mv88e6xxx_port_ppu_updates() interpretes data in the PORT_STS
register incorrectly for internal ports (ie no PPU). In these
cases, the PHY_DETECT bit indicates link status. This results
in forcing the MAC state whenever the PHY link goes down which
is not intended. As a side effect, LED's configured to show
link status stay lit even though the physical link is down.

Add a check in mac_link_down and mac_link_up to see if it
concerns an external port and only then, look at PPU status.

Fixes: 5d5b231d (net: dsa: mv88e6xxx: use PHY_DETECT in mac_link_up/mac_link_down)
Reported-by: Maarten Zanders <m.zanders@televic.com>
Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: Maarten Zanders <maarten.zanders@mind.be>
Signed-off-by: David S. Miller <davem@davemloft.net>

Fix the following coccicheck warning:
drivers/net/ethernet/mscc/ocelot.c:474:duplicated argument to & or |
drivers/net/ethernet/mscc/ocelot.c:476:duplicated argument to & or |
drivers/net/ethernet/mscc/ocelot_net.c:1627:duplicated argument
to & or |

These DEV_CLOCK_CFG_MAC_TX_RST are duplicate here.
Here should be DEV_CLOCK_CFG_MAC_RX_RST.

Fixes: e6e12df6 ("net: mscc: ocelot: convert to phylink")
Signed-off-by: Wan Jiabing <wanjiabing@vivo.com>
Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Then name of this protocol changed in commit 94531cfc ("af_unix: Add
unix_stream_proto for sockmap") because that commit added stream support
to the af_unix protocol. Renaming the existing protocol makes a ChromeOS
protocol test[1] fail now that the name has changed in
/proc/net/protocols from "UNIX" to "UNIX-DGRAM".

Let's put the name back to how it was while keeping the stream protocol
as "UNIX-STREAM" so that the procfs interface doesn't change. This fixes
the test and maintains backwards compatibility in proc.

Cc: Jiang Wang <jiang.wang@bytedance.com>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Cong Wang <cong.wang@bytedance.com>
Cc: Jakub Sitnicki <jakub@cloudflare.com>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: Dmitry Osipenko <digetx@gmail.com>
Link: https://source.chromium.org/chromiumos/chromiumos/codesearch/+/main:src/platform/tast-tests/src/chromiumos/tast/local/bundles/cros/network/supported_protocols.go;l=50;drc=e8b1c3f94cb40a054f4aa1ef1aff61e75dc38f18 [1]
Fixes: 94531cfc ("af_unix: Add unix_stream_proto for sockmap")
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

commit 12628565 ("Merge ra.kernel.org:/pub/scm/linux/kernel/git/netdev/net")
accidentally reverted the effect of
commit 1a802423 ("virtio-net: fix for skb_over_panic inside big mode")
on drivers/net/virtio_net.c

As a result, users of crosvm (which is using large packet mode)
are experiencing crashes with 5.14-rc1 and above that do not
occur with 5.13.

Crash trace:

[   61.346677] skbuff: skb_over_panic: text:ffffffff881ae2c7 len:3762 put:3762 head:ffff8a5ec8c22000 data:ffff8a5ec8c22010 tail:0xec2 end:0xec0 dev:<NULL>
[   61.369192] kernel BUG at net/core/skbuff.c:111!
[   61.372840] invalid opcode: 0000 [#1] SMP PTI
[   61.374892] CPU: 5 PID: 0 Comm: swapper/5 Not tainted 5.14.0-rc1 linux-v5.14-rc1-for-mesa-ci.tar.bz2 #1
[   61.376450] Hardware name: ChromiumOS crosvm, BIOS 0

..

[   61.393635] Call Trace:
[   61.394127]  <IRQ>
[   61.394488]  skb_put.cold+0x10/0x10
[   61.395095]  page_to_skb+0xf7/0x410
[   61.395689]  receive_buf+0x81/0x1660
[   61.396228]  ? netif_receive_skb_list_internal+0x1ad/0x2b0
[   61.397180]  ? napi_gro_flush+0x97/0xe0
[   61.397896]  ? detach_buf_split+0x67/0x120
[   61.398573]  virtnet_poll+0x2cf/0x420
[   61.399197]  __napi_poll+0x25/0x150
[   61.399764]  net_rx_action+0x22f/0x280
[   61.400394]  __do_softirq+0xba/0x257
[   61.401012]  irq_exit_rcu+0x8e/0xb0
[   61.401618]  common_interrupt+0x7b/0xa0
[   61.402270]  </IRQ>

See
https://lore.kernel.org/r/5edaa2b7c2fe4abd0347b8454b2ac032b6694e2c.camel%40collabora.com
for the report.

Apply the original 1a802423 ("virtio-net: fix for skb_over_panic inside big mode")
again, the original logic still holds:

In virtio-net's large packet mode, there is a hole in the space behind
buf.

    hdr_padded_len - hdr_len

We must take this into account when calculating tailroom.

Cc: Greg KH <gregkh@linuxfoundation.org>
Fixes: fb32856b ("virtio-net: page_to_skb() use build_skb when there's sufficient tailroom")
Fixes: 12628565 ("Merge ra.kernel.org:/pub/scm/linux/kernel/git/netdev/net")
Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Reported-by: Corentin Noël <corentin.noel@collabora.com>
Tested-by: Corentin Noël <corentin.noel@collabora.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

In case a PHY device was probed thus in the PHY_READY state, but not
configured and with no network device attached yet, we should not be
trying to shut it down because it has been brought back into reset by
phy_device_reset() towards the end of phy_probe() and anyway we have not
configured the PHY yet.

Fixes: e2f016cf ("net: phy: add a shutdown procedure")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The error code is missing in this code scenario, add the error code
'-EINVAL' to the return value 'rc'.

Eliminate the follow smatch warning:

drivers/net/ethernet/qlogic/qed/qed_main.c:1298 qed_slowpath_start()
warn: missing error code 'rc'.
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Fixes: d51e4af5 ("qed: aRFS infrastructure support")
Signed-off-by: chongjiapeng <jiapeng.chong@linux.alibaba.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

It was a documented fact that ds->ops->change_tag_protocol() offered
rtnetlink mutex protection to the switch driver, since there was an
ASSERT_RTNL right before the call in dsa_switch_change_tag_proto()
(initiated from sysfs).

The blamed commit introduced another call path for
ds->ops->change_tag_protocol() which does not hold the rtnl_mutex.
This is:

dsa_tree_setup
-> dsa_tree_setup_switches
   -> dsa_switch_setup
      -> dsa_switch_setup_tag_protocol
         -> ds->ops->change_tag_protocol()
   -> dsa_port_setup
      -> dsa_slave_create
         -> register_netdevice(slave_dev)
-> dsa_tree_setup_master
   -> dsa_master_setup
      -> dev->dsa_ptr = cpu_dp

The reason why the rtnl_mutex is held in the sysfs call path is to
ensure that, once the master and all the DSA interfaces are down (which
is required so that no packets flow), they remain down during the
tagging protocol change.

The above calling order illustrates the fact that it should not be risky
to change the initial tagging protocol to the one specified in the
device tree at the given time:

- packets cannot enter the dsa_switch_rcv() packet type handler since
  netdev_uses_dsa() for the master will not yet return true, since
  dev->dsa_ptr has not yet been populated

- packets cannot enter the dsa_slave_xmit() function because no DSA
  interface has yet been registered

So from the DSA core's perspective, holding the rtnl_mutex is indeed not
necessary.

Yet, drivers may need to do things which need rtnl_mutex protection. For
example:

felix_set_tag_protocol
-> felix_setup_tag_8021q
   -> dsa_tag_8021q_register
      -> dsa_tag_8021q_setup
         -> dsa_tag_8021q_port_setup
            -> vlan_vid_add
               -> ASSERT_RTNL

These drivers do not really have a choice to take the rtnl_mutex
themselves, since in the sysfs case, the rtnl_mutex is already held.

Fixes: deff7107 ("net: dsa: Allow default tag protocol to be overridden from DT")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The driver can call card->isac.release() function from an atomic
context.

Fix this by calling this function after releasing the lock.

The following log reveals it:

[   44.168226 ] BUG: sleeping function called from invalid context at kernel/workqueue.c:3018
[   44.168941 ] in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 5475, name: modprobe
[   44.169574 ] INFO: lockdep is turned off.
[   44.169899 ] irq event stamp: 0
[   44.170160 ] hardirqs last  enabled at (0): [<0000000000000000>] 0x0
[   44.170627 ] hardirqs last disabled at (0): [<ffffffff814209ed>] copy_process+0x132d/0x3e00
[   44.171240 ] softirqs last  enabled at (0): [<ffffffff81420a1a>] copy_process+0x135a/0x3e00
[   44.171852 ] softirqs last disabled at (0): [<0000000000000000>] 0x0
[   44.172318 ] Preemption disabled at:
[   44.172320 ] [<ffffffffa009b0a9>] nj_release+0x69/0x500 [netjet]
[   44.174441 ] Call Trace:
[   44.174630 ]  dump_stack_lvl+0xa8/0xd1
[   44.174912 ]  dump_stack+0x15/0x17
[   44.175166 ]  ___might_sleep+0x3a2/0x510
[   44.175459 ]  ? nj_release+0x69/0x500 [netjet]
[   44.175791 ]  __might_sleep+0x82/0xe0
[   44.176063 ]  ? start_flush_work+0x20/0x7b0
[   44.176375 ]  start_flush_work+0x33/0x7b0
[   44.176672 ]  ? trace_irq_enable_rcuidle+0x85/0x170
[   44.177034 ]  ? kasan_quarantine_put+0xaa/0x1f0
[   44.177372 ]  ? kasan_quarantine_put+0xaa/0x1f0
[   44.177711 ]  __flush_work+0x11a/0x1a0
[   44.177991 ]  ? flush_work+0x20/0x20
[   44.178257 ]  ? lock_release+0x13c/0x8f0
[   44.178550 ]  ? __kasan_check_write+0x14/0x20
[   44.178872 ]  ? do_raw_spin_lock+0x148/0x360
[   44.179187 ]  ? read_lock_is_recursive+0x20/0x20
[   44.179530 ]  ? __kasan_check_read+0x11/0x20
[   44.179846 ]  ? do_raw_spin_unlock+0x55/0x900
[   44.180168 ]  ? ____kasan_slab_free+0x116/0x140
[   44.180505 ]  ? _raw_spin_unlock_irqrestore+0x41/0x60
[   44.180878 ]  ? skb_queue_purge+0x1a3/0x1c0
[   44.181189 ]  ? kfree+0x13e/0x290
[   44.181438 ]  flush_work+0x17/0x20
[   44.181695 ]  mISDN_freedchannel+0xe8/0x100
[   44.182006 ]  isac_release+0x210/0x260 [mISDNipac]
[   44.182366 ]  nj_release+0xf6/0x500 [netjet]
[   44.182685 ]  nj_remove+0x48/0x70 [netjet]
[   44.182989 ]  pci_device_remove+0xa9/0x250
Signed-off-by: Zheyu Ma <zheyuma97@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Bridging, and possibly other upper stack gizmos, adds the
lower device's netdev->dev_addr to its own uc list, and
then requests it be deleted when the upper bridge device is
removed.  This delete request also happens with the bridging
vlan_filtering is enabled and then disabled.

Bonding has a similar behavior with the uc list, but since it
also uses set_mac to manage netdev->dev_addr, it doesn't have
the same the failure case.

Because we store our netdev->dev_addr in our uc list, we need
to ignore the delete request from dev_uc_sync so as to not
lose the address and all hope of communicating.  Note that
ndo_set_mac_address is expressly changing netdev->dev_addr,
so no limitation is set there.

Fixes: 2a654540 ("ionic: Add Rx filter and rx_mode ndo support")
Signed-off-by: Shannon Nelson <snelson@pensando.io>
Signed-off-by: David S. Miller <davem@davemloft.net>

Fix error handling in mana_create_rxq() when
cq->gdma_id >= gc->max_num_cqs.

Fixes: ca9c54d2 ("net: mana: Add a driver for Microsoft Azure Network Adapter (MANA)")
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Link: https://lore.kernel.org/r/1633698691-31721-1-git-send-email-haiyangz@microsoft.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

The cmtp_add_connection() would add a cmtp session to a controller
and run a kernel thread to process cmtp.

	__module_get(THIS_MODULE);
	session->task = kthread_run(cmtp_session, session, "kcmtpd_ctr_%d",
								session->num);

During this process, the kernel thread would call detach_capi_ctr()
to detach a register controller. if the controller
was not attached yet, detach_capi_ctr() would
trigger an array-index-out-bounds bug.

[   46.866069][ T6479] UBSAN: array-index-out-of-bounds in
drivers/isdn/capi/kcapi.c:483:21
[   46.867196][ T6479] index -1 is out of range for type 'capi_ctr *[32]'
[   46.867982][ T6479] CPU: 1 PID: 6479 Comm: kcmtpd_ctr_0 Not tainted
5.15.0-rc2+ #8
[   46.869002][ T6479] Hardware name: QEMU Standard PC (i440FX + PIIX,
1996), BIOS 1.14.0-2 04/01/2014
[   46.870107][ T6479] Call Trace:
[   46.870473][ T6479]  dump_stack_lvl+0x57/0x7d
[   46.870974][ T6479]  ubsan_epilogue+0x5/0x40
[   46.871458][ T6479]  __ubsan_handle_out_of_bounds.cold+0x43/0x48
[   46.872135][ T6479]  detach_capi_ctr+0x64/0xc0
[   46.872639][ T6479]  cmtp_session+0x5c8/0x5d0
[   46.873131][ T6479]  ? __init_waitqueue_head+0x60/0x60
[   46.873712][ T6479]  ? cmtp_add_msgpart+0x120/0x120
[   46.874256][ T6479]  kthread+0x147/0x170
[   46.874709][ T6479]  ? set_kthread_struct+0x40/0x40
[   46.875248][ T6479]  ret_from_fork+0x1f/0x30
[   46.875773][ T6479]
Signed-off-by: Xiaolong Huang <butterflyhuangxx@gmail.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20211008065830.305057-1-butterflyhuangxx@gmail.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Introduction of lockless subqueues broke the class statistics.
Before the change stats were accumulated in `bstats' and `qstats'
on the stack which was then copied to struct gnet_dump.

After the change the `bstats' and `qstats' are initialized to 0
and never updated, yet still fed to gnet_dump. The code updates
the global qdisc->cpu_bstats and qdisc->cpu_qstats instead,
clobbering them. Most likely a copy-paste error from the code in
mqprio_dump().

__gnet_stats_copy_basic() and __gnet_stats_copy_queue() accumulate
the values for per-CPU case but for global stats they overwrite
the value, so only stats from the last loop iteration / tc end up
in sch->[bq]stats.

Use the on-stack [bq]stats variables again and add the stats manually
in the global case.

Fixes: ce679e8d ("net: sched: add support for TCQ_F_NOLOCK subqueues to sch_mqprio")
Cc: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
https://lore.kernel.org/all/20211007175000.2334713-2-bigeasy@linutronix.de/Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Vladimir Oltean says:

====================
DSA bridge TX forwarding offload fixes - part 1

This is part 1 of a series of fixes to the bridge TX forwarding offload
feature introduced for v5.15. Sadly, the other fixes are so intrusive
that they cannot be reasonably be sent to the "net" tree, as they also
include API changes. So they are left as part 2 for net-next.
====================

Link: https://lore.kernel.org/r/20211007164711.2897238-1-vladimir.oltean@nxp.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Similar to commit 6087175b ("net: dsa: mt7530: use independent VLAN
learning on VLAN-unaware bridges"), software forwarding between an
unoffloaded LAG port (a bonding interface with an unsupported policy)
and a mv88e6xxx user port directly under a bridge is broken.

We adopt the same strategy, which is to make the standalone ports not
find any ATU entry learned on a bridge port.

Theory: the mv88e6xxx ATU is looked up by FID and MAC address. There are
as many FIDs as VIDs (4096). The FID is derived from the VID when
possible (the VTU maps a VID to a FID), with a fallback to the port
based default FID value when not (802.1Q Mode is disabled on the port,
or the classified VID isn't present in the VTU).

The mv88e6xxx driver makes the following use of FIDs and VIDs:

- the port's DefaultVID (to which untagged & pvid-tagged packets get
  classified) is 0 and is absent from the VTU, so this kind of packets is
  processed in FID 0, the default FID assigned by mv88e6xxx_setup_port.

- every time a bridge VLAN is created, mv88e6xxx_port_vlan_join() ->
  mv88e6xxx_atu_new() associates a FID with that VID which increases
  linearly starting from 1. Like this:

  bridge vlan add dev lan0 vid 100 # FID 1
  bridge vlan add dev lan1 vid 100 # still FID 1
  bridge vlan add dev lan2 vid 1024 # FID 2

The FID allocation made by the driver is sub-optimal for the following
reasons:

(a) A standalone port has a DefaultPVID of 0 and a default FID of 0 too.
    A VLAN-unaware bridged port has a DefaultPVID of 0 and a default FID
    of 0 too. The difference is that the bridged ports may learn ATU
    entries, while the standalone port has the requirement that it must
    not, and must not find them either. Standalone ports must not use
    the same FID as ports belonging to a bridge. All standalone ports
    can use the same FID, since the ATU will never have an entry in
    that FID.

(b) Multiple VLAN-unaware bridges will all use a DefaultPVID of 0 and a
    default FID of 0 on all their ports. The FDBs will not be isolated
    between these bridges. Every VLAN-unaware bridge must use the same
    FID on all its ports, different from the FID of other bridge ports.

(c) Each bridge VLAN uses a unique FID which is useful for Independent
    VLAN Learning, but the same VLAN ID on multiple VLAN-aware bridges
    will result in the same FID being used by mv88e6xxx_atu_new().
    The correct behavior is for VLAN 1 in br0 to have a different FID
    compared to VLAN 1 in br1.

This patch cannot fix all the above. Traditionally the DSA framework did
not care about this, and the reality is that DSA core involvement is
needed for the aforementioned issues to be solved. The only thing we can
solve here is an issue which does not require API changes, and that is
issue (a), aka use a different FID for standalone ports vs ports under
VLAN-unaware bridges.

The first step is deciding what VID and FID to use for standalone ports,
and what VID and FID for bridged ports. The 0/0 pair for standalone
ports is what they used up till now, let's keep using that. For bridged
ports, there are 2 cases:

- VLAN-aware ports will never end up using the port default FID, because
  packets will always be classified to a VID in the VTU or dropped
  otherwise. The FID is the one associated with the VID in the VTU.

- On VLAN-unaware ports, we _could_ leave their DefaultVID (pvid) at
  zero (just as in the case of standalone ports), and just change the
  port's default FID from 0 to a different number (say 1).

However, Tobias points out that there is one more requirement to cater to:
cross-chip bridging. The Marvell DSA header does not carry the FID in
it, only the VID. So once a packet crosses a DSA link, if it has a VID
of zero it will get classified to the default FID of that cascade port.
Relying on a port default FID for upstream cascade ports results in
contradictions: a default FID of 0 breaks ATU isolation of bridged ports
on the downstream switch, a default FID of 1 breaks standalone ports on
the downstream switch.

So not only must standalone ports have different FIDs compared to
bridged ports, they must also have different DefaultVID values.
IEEE 802.1Q defines two reserved VID values: 0 and 4095. So we simply
choose 4095 as the DefaultVID of ports belonging to VLAN-unaware
bridges, and VID 4095 maps to FID 1.

For the xmit operation to look up the same ATU database, we need to put
VID 4095 in DSA tags sent to ports belonging to VLAN-unaware bridges
too. All shared ports are configured to map this VID to the bridging
FID, because they are members of that VLAN in the VTU. Shared ports
don't need to have 802.1QMode enabled in any way, they always parse the
VID from the DSA header, they don't need to look at the 802.1Q header.

We install VID 4095 to the VTU in mv88e6xxx_setup_port(), with the
mention that mv88e6xxx_vtu_setup() which was located right below that
call was flushing the VTU so those entries wouldn't be preserved.
So we need to relocate the VTU flushing prior to the port initialization
during ->setup(). Also note that this is why it is safe to assume that
VID 4095 will get associated with FID 1: the user ports haven't been
created, so there is no avenue for the user to create a bridge VLAN
which could otherwise race with the creation of another FID which would
otherwise use up the non-reserved FID value of 1.

[ Currently mv88e6xxx_port_vlan_join() doesn't have the option of
  specifying a preferred FID, it always calls mv88e6xxx_atu_new(). ]

mv88e6xxx_port_db_load_purge() is the function to access the ATU for
FDB/MDB entries, and it used to determine the FID to use for
VLAN-unaware FDB entries (VID=0) using mv88e6xxx_port_get_fid().
But the driver only called mv88e6xxx_port_set_fid() once, during probe,
so no surprises, the port FID was always 0, the call to get_fid() was
redundant. As much as I would have wanted to not touch that code, the
logic is broken when we add a new FID which is not the port-based
default. Now the port-based default FID only corresponds to standalone
ports, and FDB/MDB entries belong to the bridging service. So while in
the future, when the DSA API will support FDB isolation, we will have to
figure out the FID based on the bridge number, for now there's a single
bridging FID, so hardcode that.

Lastly, the tagger needs to check, when it is transmitting a VLAN
untagged skb, whether it is sending it towards a bridged or a standalone
port. When we see it is bridged we assume the bridge is VLAN-unaware.
Not because it cannot be VLAN-aware but:

- if we are transmitting from a VLAN-aware bridge we are likely doing so
  using TX forwarding offload. That code path guarantees that skbs have
  a vlan hwaccel tag in them, so we would not enter the "else" branch
  of the "if (skb->protocol == htons(ETH_P_8021Q))" condition.

- if we are transmitting on behalf of a VLAN-aware bridge but with no TX
  forwarding offload (no PVT support, out of space in the PVT, whatever),
  we would indeed be transmitting with VLAN 4095 instead of the bridge
  device's pvid. However we would be injecting a "From CPU" frame, and
  the switch won't learn from that - it only learns from "Forward" frames.
  So it is inconsequential for address learning. And VLAN 4095 is
  absolutely enough for the frame to exit the switch, since we never
  remove that VLAN from any port.

Fixes: 57e661aa ("net: dsa: mv88e6xxx: Link aggregation support")
Reported-by: Tobias Waldekranz <tobias@waldekranz.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

The VLAN support in mv88e6xxx has a loaded history. Commit 2ea7a679
("net: dsa: Don't add vlans when vlan filtering is disabled") noticed
some issues with VLAN and decided the best way to deal with them was to
make the DSA core ignore VLANs added by the bridge while VLAN awareness
is turned off. Those issues were never explained, just presented as
"at least one corner case".

That approach had problems of its own, presented by
commit 54a0ed0d ("net: dsa: provide an option for drivers to always
receive bridge VLANs") for the DSA core, followed by
commit 1fb74191 ("net: dsa: mv88e6xxx: fix vlan setup") which
applied ds->configure_vlan_while_not_filtering = true for mv88e6xxx in
particular.

We still don't know what corner case Andrew saw when he wrote
commit 2ea7a679 ("net: dsa: Don't add vlans when vlan filtering is
disabled"), but Tobias now reports that when we use TX forwarding
offload, pinging an external station from the bridge device is broken if
the front-facing DSA user port has flooding turned off. The full
description is in the link below, but for short, when a mv88e6xxx port
is under a VLAN-unaware bridge, it inherits that bridge's pvid.
So packets ingressing a user port will be classified to e.g. VID 1
(assuming that value for the bridge_default_pvid), whereas when
tag_dsa.c xmits towards a user port, it always sends packets using a VID
of 0 if that port is standalone or under a VLAN-unaware bridge - or at
least it did so prior to commit d82f8ab0 ("net: dsa: tag_dsa:
offload the bridge forwarding process").

In any case, when there is a conversation between the CPU and a station
connected to a user port, the station's MAC address is learned in VID 1
but the CPU tries to transmit through VID 0. The packets reach the
intended station, but via flooding and not by virtue of matching the
existing ATU entry.

DSA has established (and enforced in other drivers: sja1105, felix,
mt7530) that a VLAN-unaware port should use a private pvid, and not
inherit the one from the bridge. The bridge's pvid should only be
inherited when that bridge is VLAN-aware, so all state transitions need
to be handled. On the other hand, all bridge VLANs should sit in the VTU
starting with the moment when the bridge offloads them via switchdev,
they are just not used.

This solves the problem that Tobias sees because packets ingressing on
VLAN-unaware user ports now get classified to VID 0, which is also the
VID used by tag_dsa.c on xmit.

Fixes: d82f8ab0 ("net: dsa: tag_dsa: offload the bridge forwarding process")
Link: https://patchwork.kernel.org/project/netdevbpf/patch/20211003222312.284175-2-vladimir.oltean@nxp.com/#24491503Reported-by: Tobias Waldekranz <tobias@waldekranz.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

The present code is structured this way due to an incomplete thought
process. In Documentation/networking/switchdev.rst we document that if a
bridge is VLAN-unaware, then the presence or lack of a pvid on a bridge
port (or on the bridge itself, for that matter) should not affect the
ability to receive and transmit tagged or untagged packets.

If the bridge on behalf of which we are sending this packet is
VLAN-aware, then the TX forwarding offload API ensures that the skb will
be VLAN-tagged (if the packet was sent by user space as untagged, it
will get transmitted town to the driver as tagged with the bridge
device's pvid). But if the bridge is VLAN-unaware, it may or may not be
VLAN-tagged. In fact the logic to insert the bridge's PVID came from the
idea that we should emulate what is being done in the VLAN-aware case.
But we shouldn't.

It appears that injecting packets using a VLAN ID of 0 serves the
purpose of forwarding the packets to the egress port with no VLAN tag
added or stripped by the hardware, and no filtering being performed.
So we can simply remove the superfluous logic.

One reason why this logic is broken is that when CONFIG_BRIDGE_VLAN_FILTERING=n,
we call br_vlan_get_pvid_rcu() but that returns an error and we do error
out, dropping all packets on xmit. Not really smart. This is also an
issue when the user deletes the bridge pvid:

$ bridge vlan del dev br0 vid 1 self

As mentioned, in both cases, packets should still flow freely, and they
do just that on any net device where the bridge is not offloaded, but on
mv88e6xxx they don't.

Fixes: d82f8ab0 ("net: dsa: tag_dsa: offload the bridge forwarding process")
Reported-by: Andrew Lunn <andrew@lunn.ch>
Link: https://patchwork.kernel.org/project/netdevbpf/patch/20211003155141.2241314-1-andrew@lunn.ch/
Link: https://patchwork.kernel.org/project/netdevbpf/patch/20210928233708.1246774-1-vladimir.oltean@nxp.com/Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

The dp->bridge_num is zero-based, with -1 being the encoding for an
invalid value. But dsa_bridge_num_put used to check for an invalid value
by comparing bridge_num with 0, which is of course incorrect.

The result is that the bridge_num will never get cleared by
dsa_bridge_num_put, and further port joins to other bridges will get a
bridge_num larger than the previous one, and once all the available
bridges with TX forwarding offload supported by the hardware get
exhausted, the TX forwarding offload feature is simply disabled.

In the case of sja1105, 7 iterations of the loop below are enough to
exhaust the TX forwarding offload bits, and further bridge joins operate
without that feature.

ip link add br0 type bridge vlan_filtering 1

while :; do
        ip link set sw0p2 master br0 && sleep 1
        ip link set sw0p2 nomaster && sleep 1
done

This issue is enough of an indication that having the dp->bridge_num
invalid encoding be a negative number is prone to bugs, so this will be
changed to a one-based value, with the dp->bridge_num of zero being the
indication of no bridge. However, that is material for net-next.

Fixes: f5e165e7 ("net: dsa: track unique bridge numbers across all DSA switch trees")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

The nci_core_conn_close_rsp_packet() function will release the conn_info
with given conn_id. However, it needs to set the rf_conn_info to NULL to
prevent other routines like nci_rf_intf_activated_ntf_packet() to trigger
the UAF.
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Signed-off-by: Lin Ma <linma@zju.edu.cn>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Commit 8f3d65c1 ("net/smc: fix wait on already cleared link")
introduced link refcounting to avoid waits on already cleared links.
This patch extents and improves the refcounting to cover all
remaining possible cases for this kind of error situation.

Fixes: 15e1b99a ("net/smc: no WR buffer wait for terminating link group")
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Merge branch 'stmmac-regression-fix'

Herve Codina says:

====================
net: stmmac: fix regression on SPEAr3xx SOC

The ethernet driver used on old SPEAr3xx soc was previously supported on old
kernel. Some regressions were introduced during the different updates leading
to a broken driver for this soc.

This series fixes these regressions and brings back ethernet on SPEAr3xx.
Tested on a SPEAr320 board.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

On SPEAr3xx, ethernet driver is not compatible with the SPEAr600
one.
Indeed, SPEAr3xx uses an earlier version of this IP (v3.40) and
needs some driver tuning compare to SPEAr600.

The v3.40 IP support was added to stmmac driver and this patch
fixes this issue and use the correct compatible string for
SPEAr3xx
Signed-off-by: Herve Codina <herve.codina@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>