Any link state change that's done prior to net device registration
isn't reflected on the state, thus the operational state is left
obsolete, with 'UNKNOWN' status.

To resolve the issue, query link state from FW upon open operations
to ensure operational state is updated.

Fixes: c27a02cd ("mlx4_en: Add driver for Mellanox ConnectX 10GbE NIC")
Signed-off-by: Lama Kayal <lkayal@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Fix the args to fprintf(). Splitting the message ends up passing
incorrect arg for "sigurg %d" and an extra arg overall. The test
result message ends up incorrect.

test_unix_oob.c: In function ‘main’:
test_unix_oob.c:274:43: warning: format ‘%d’ expects argument of type ‘int’, but argument 3 has type ‘char *’ [-Wformat=]
  274 |   fprintf(stderr, "Test 3 failed, sigurg %d len %d OOB %c ",
      |                                          ~^
      |                                           |
      |                                           int
      |                                          %s
  275 |   "atmark %d\n", signal_recvd, len, oob, atmark);
      |   ~~~~~~~~~~~~~
      |   |
      |   char *
test_unix_oob.c:274:19: warning: too many arguments for format [-Wformat-extra-args]
  274 |   fprintf(stderr, "Test 3 failed, sigurg %d len %d OOB %c ",
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Due to the inclusion of nvmem handling into the mac-address getter
function of_get_mac_address() by
commit d01f449c ("of_net: add NVMEM support to of_get_mac_address")
it is now possible to get a -EPROBE_DEFER return code. Which did cause
bgmac to assign a random ethernet address.

This exact issue happened on my Meraki MR32. The nvmem provider is
an EEPROM (at24c64) which gets instantiated once the module
driver is loaded... This happens once the filesystem becomes available.

With this patch, bgmac_probe() will propagate the -EPROBE_DEFER error.
Then the driver subsystem will reschedule the probe at a later time.

Cc: Petr Štetiar <ynezz@true.cz>
Cc: Michael Walle <michael@walle.cc>
Fixes: d01f449c ("of_net: add NVMEM support to of_get_mac_address")
Signed-off-by: Christian Lamparter <chunkeey@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Commit 86f8b1c0 ("net: dsa: Do not make user port errors fatal")
decided it was fine to ignore errors on certain ports that fail to
probe, and go on with the ports that do probe fine.

Commit fb6ec87f ("net: dsa: Fix type was not set for devlink port")
noticed that devlink_port_type_eth_set(dlp, dp->slave); does not get
called, and devlink notices after a timeout of 3600 seconds and prints a
WARN_ON. So it went ahead to unregister the devlink port. And because
there exists an UNUSED port flavour, we actually re-register the devlink
port as UNUSED.

Commit 08156ba4 ("net: dsa: Add devlink port regions support to
DSA") added devlink port regions, which are set up by the driver and not
by DSA.

When we trigger the devlink port deregistration and reregistration as
unused, devlink now prints another WARN_ON, from here:

devlink_port_unregister:
	WARN_ON(!list_empty(&devlink_port->region_list));

So the port still has regions, which makes sense, because they were set
up by the driver, and the driver doesn't know we're unregistering the
devlink port.

Somebody needs to tear them down, and optionally (actually it would be
nice, to be consistent) set them up again for the new devlink port.

But DSA's layering stays in our way quite badly here.

The options I've considered are:

1. Introduce a function in devlink to just change a port's type and
   flavour. No dice, devlink keeps a lot of state, it really wants the
   port to not be registered when you set its parameters, so changing
   anything can only be done by destroying what we currently have and
   recreating it.

2. Make DSA cache the parameters passed to dsa_devlink_port_region_create,
   and the region returned, keep those in a list, then when the devlink
   port unregister needs to take place, the existing devlink regions are
   destroyed by DSA, and we replay the creation of new regions using the
   cached parameters. Problem: mv88e6xxx keeps the region pointers in
   chip->ports[port].region, and these will remain stale after DSA frees
   them. There are many things DSA can do, but updating mv88e6xxx's
   private pointers is not one of them.

3. Just let the driver do it (i.e. introduce a very specific method
   called ds->ops->port_reinit_as_unused, which unregisters its devlink
   port devlink regions, then the old devlink port, then registers the
   new one, then the devlink port regions for it). While it does work,
   as opposed to the others, it's pretty horrible from an API
   perspective and we can do better.

4. Introduce a new pair of methods, ->port_setup and ->port_teardown,
   which in the case of mv88e6xxx must register and unregister the
   devlink port regions. Call these 2 methods when the port must be
   reinitialized as unused.

Naturally, I went for the 4th approach.

Fixes: 08156ba4 ("net: dsa: Add devlink port regions support to DSA")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The MODULE_DEVICE_TABLE already creates proper alias for platform
driver.  Having another MODULE_ALIAS causes the alias to be duplicated.
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Colin Foster says:

====================
ocelot phylink fixes

When the ocelot driver was migrated to phylink, e6e12df6 ("net:
mscc: ocelot: convert to phylink") there were two additional writes to
registers that became stale. One write was to DEV_CLOCK_CFG and one was
to ANA_PFC_PCF_CFG.

Both of these writes referenced the variable "speed" which originally
was set to OCELOT_SPEED_{10,100,1000,2500}. These macros expand to
values of 3, 2, 1, or 0, respectively. After the update, the variable
speed is set to SPEED_{10,100,1000,2500} which expand to 10, 100, 1000,
and 2500. So invalid values were getting written to the two registers,
which would lead to either a lack of functionality or undefined
funcationality.

Fixing these values was the intent of v1 of this patch set - submitted
as "[PATCH v1 net] net: ethernet: mscc: ocelot: bug fix when writing MAC
speed"

During that review it was determined that both writes were actually
unnecessary. DEV_CLOCK_CFG is a duplicate write, so can be removed
entirely. This was accidentally submitted as as a new, lone patch titled
"[PATCH v1 net] net: mscc: ocelot: remove buggy duplicate write to
DEV_CLOCK_CFG". This is part of what is considered v2 of this patch set.

Additionally, the write to ANA_PFC_PFC_CFG is also unnecessary. Priority
flow contol is disabled, so configuring it is useless and should be
removed. This was also submitted as a new, lone patch titled "[PATCH v1
net] net: mscc: ocelot: remove buggy and useless write to ANA_PFC_PFC_CFG".
This is the rest of what is considered v2 of this patch set.

v3
Identical to v2, but fixes the patch numbering to v3 and submitting the
two changes as a patch set.

v2
Note: I misunderstood and submitted two new "v1" patches instead of a
single "v2" patch set.
- Remove the buggy writes altogher
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

When updating ocelot to use phylink, a second write to DEV_CLOCK_CFG was
mistakenly left in. It used the variable "speed" which, previously, would
would have been assigned a value of OCELOT_SPEED_1000. In phylink the
variable is be SPEED_1000, which is invalid for the
DEV_CLOCK_LINK_SPEED macro. Removing it as unnecessary and buggy.

Fixes: e6e12df6 ("net: mscc: ocelot: convert to phylink")
Signed-off-by: Colin Foster <colin.foster@in-advantage.com>
Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

A useless write to ANA_PFC_PFC_CFG was left in while refactoring ocelot to
phylink. Since priority flow control is disabled, writing the speed has no
effect.

Further, it was using ethtool.h SPEED_ instead of OCELOT_SPEED_ macros,
which are incorrectly offset for GENMASK.

Lastly, for priority flow control to properly function, some scenarios
would rely on the rate adaptation from the PCS while the MAC speed would
be fixed. So it isn't used, and even if it was, neither "speed" nor
"mac_speed" are necessarily the correct values to be used.

Fixes: e6e12df6 ("net: mscc: ocelot: convert to phylink")
Signed-off-by: Colin Foster <colin.foster@in-advantage.com>
Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

lock_sock_fast() and lock_sock_nested() contain lockdep annotations for the
sock::sk_lock.owned 'mutex'. sock::sk_lock.owned is not a regular mutex. It
is just lockdep wise equivalent. In fact it's an open coded trivial mutex
implementation with some interesting features.

sock::sk_lock.slock is a regular spinlock protecting the 'mutex'
representation sock::sk_lock.owned which is a plain boolean. If 'owned' is
true, then some other task holds the 'mutex', otherwise it is uncontended.
As this locking construct is obviously endangered by lock ordering issues as
any other locking primitive it got lockdep annotated via a dedicated
dependency map sock::sk_lock.dep_map which has to be updated at the lock
and unlock sites.

lock_sock_nested() is a straight forward 'mutex' lock operation:

  might_sleep();
  spin_lock_bh(sock::sk_lock.slock)
  while (!try_lock(sock::sk_lock.owned)) {
      spin_unlock_bh(sock::sk_lock.slock);
      wait_for_release();
      spin_lock_bh(sock::sk_lock.slock);
  }

The lockdep annotation for sock::sk_lock.owned is for unknown reasons
_after_ the lock has been acquired, i.e. after the code block above and
after releasing sock::sk_lock.slock, but inside the bottom halves disabled
region:

  spin_unlock(sock::sk_lock.slock);
  mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
  local_bh_enable();

The placement after the unlock is obvious because otherwise the
mutex_acquire() would nest into the spin lock held region.

But that's from the lockdep perspective still the wrong place:

 1) The mutex_acquire() is issued _after_ the successful acquisition which
    is pointless because in a dead lock scenario this point is never
    reached which means that if the deadlock is the first instance of
    exposing the wrong lock order lockdep does not have a chance to detect
    it.

 2) It only works because lockdep is rather lax on the context from which
    the mutex_acquire() is issued. Acquiring a mutex inside a bottom halves
    and therefore non-preemptible region is obviously invalid, except for a
    trylock which is clearly not the case here.

    This 'works' stops working on RT enabled kernels where the bottom halves
    serialization is done via a local lock, which exposes this misplacement
    because the 'mutex' and the local lock nest the wrong way around and
    lockdep complains rightfully about a lock inversion.

The placement is wrong since the initial commit a5b5bb9a ("[PATCH]
lockdep: annotate sk_locks") which introduced this.

Fix it by moving the mutex_acquire() in front of the actual lock
acquisition, which is what the regular mutex_lock() operation does as well.

lock_sock_fast() is not that straight forward. It looks at the first glance
like a convoluted trylock operation:

  spin_lock_bh(sock::sk_lock.slock)
  if (!sock::sk_lock.owned)
      return false;
  while (!try_lock(sock::sk_lock.owned)) {
      spin_unlock_bh(sock::sk_lock.slock);
      wait_for_release();
      spin_lock_bh(sock::sk_lock.slock);
  }
  spin_unlock(sock::sk_lock.slock);
  mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
  local_bh_enable();
  return true;

But that's not the case: lock_sock_fast() is an interesting optimization
for short critical sections which can run with bottom halves disabled and
sock::sk_lock.slock held. This allows to shortcut the 'mutex' operation in
the non contended case by preventing other lockers to acquire
sock::sk_lock.owned because they are blocked on sock::sk_lock.slock, which
in turn avoids the overhead of doing the heavy processing in release_sock()
including waking up wait queue waiters.

In the contended case, i.e. when sock::sk_lock.owned == true the behavior
is the same as lock_sock_nested().

Semantically this shortcut means, that the task acquired the 'mutex' even
if it does not touch the sock::sk_lock.owned field in the non-contended
case. Not telling lockdep about this shortcut acquisition is hiding
potential lock ordering violations in the fast path.

As a consequence the same reasoning as for the above lock_sock_nested()
case vs. the placement of the lockdep annotation applies.

The current placement of the lockdep annotation was just copied from
the original lock_sock(), now renamed to lock_sock_nested(),
implementation.

Fix this by moving the mutex_acquire() in front of the actual lock
acquisition and adding the corresponding mutex_release() into
unlock_sock_fast(). Also document the fast path return case with a comment.
Reported-by: Sebastian Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: netdev@vger.kernel.org
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The file sja1105.txt was converted to nxp,sja1105.yaml.
Signed-off-by: Alejandro Concepcion-Rodriguez <asconcepcion@acoro.eu>
Signed-off-by: David S. Miller <davem@davemloft.net>

When IGC=y and PTP_1588_CLOCK=m, the ptp_*() interface family is
not available to the igc driver. Make this driver depend on
PTP_1588_CLOCK_OPTIONAL so that it will build without errors.

Various igc commits have used ptp_*() functions without checking
that PTP_1588_CLOCK is enabled. Fix all of these here.

Fixes these build errors:

ld: drivers/net/ethernet/intel/igc/igc_main.o: in function `igc_msix_other':
igc_main.c:(.text+0x6494): undefined reference to `ptp_clock_event'
ld: igc_main.c:(.text+0x64ef): undefined reference to `ptp_clock_event'
ld: igc_main.c:(.text+0x6559): undefined reference to `ptp_clock_event'
ld: drivers/net/ethernet/intel/igc/igc_ethtool.o: in function `igc_ethtool_get_ts_info':
igc_ethtool.c:(.text+0xc7a): undefined reference to `ptp_clock_index'
ld: drivers/net/ethernet/intel/igc/igc_ptp.o: in function `igc_ptp_feature_enable_i225':
igc_ptp.c:(.text+0x330): undefined reference to `ptp_find_pin'
ld: igc_ptp.c:(.text+0x36f): undefined reference to `ptp_find_pin'
ld: drivers/net/ethernet/intel/igc/igc_ptp.o: in function `igc_ptp_init':
igc_ptp.c:(.text+0x11cd): undefined reference to `ptp_clock_register'
ld: drivers/net/ethernet/intel/igc/igc_ptp.o: in function `igc_ptp_stop':
igc_ptp.c:(.text+0x12dd): undefined reference to `ptp_clock_unregister'
ld: drivers/platform/x86/dell/dell-wmi-privacy.o: in function `dell_privacy_wmi_probe':

Fixes: 64433e5b ("igc: Enable internal i225 PPS")
Fixes: 60dbede0 ("igc: Add support for ethtool GET_TS_INFO command")
Fixes: 87938851 ("igc: enable auxiliary PHC functions for the i225")
Fixes: 5f295805 ("igc: Add basic skeleton for PTP")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Ederson de Souza <ederson.desouza@intel.com>
Cc: Tony Nguyen <anthony.l.nguyen@intel.com>
Cc: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Cc: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Jesse Brandeburg <jesse.brandeburg@intel.com>
Cc: intel-wired-lan@lists.osuosl.org
Acked-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The only struct dim_sample member that does not get
initialized by dim_update_sample() is comp_ctr. (There
is special API to initialize comp_ctr:
dim_update_sample_with_comps(), and it is currently used
only for RDMA.) comp_ctr is used to compute curr_stats->cmps
and curr_stats->cpe_ratio (see dim_calc_stats()) which in
turn are consumed by the rdma_dim_*() API.  Therefore,
functionally, the net_dim*() API consumers are not affected.
Nevertheless, fix the computation of statistics based
on an uninitialized variable, even if the mentioned statistics
are not used at the moment.

Fixes: ae0e6a5d ("enetc: Add adaptive interrupt coalescing")
Signed-off-by: Claudiu Manoil <claudiu.manoil@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

irq_set_affinity_hit() stores a reference to the cpumask_t
parameter in the irq descriptor, and that reference can be
accessed later from irq_affinity_hint_proc_show(). Since
the cpu_mask parameter passed to irq_set_affinity_hit() has
only temporary storage (it's on the stack memory), later
accesses to it are illegal. Thus reads from the corresponding
procfs affinity_hint file can result in paging request oops.

The issue is fixed by the get_cpu_mask() helper, which provides
a permanent storage for the cpumask_t parameter.

Fixes: d4fd0404 ("enetc: Introduce basic PF and VF ENETC ethernet drivers")
Signed-off-by: Claudiu Manoil <claudiu.manoil@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

We try to use build_skb() if we had sufficient tailroom. But we forget
to release the unused pages chained via private in big mode which will
leak pages. Fixing this by release the pages after building the skb in
big mode.

Cc: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Fixes: fb32856b ("virtio-net: page_to_skb() use build_skb when there's sufficient tailroom")
Signed-off-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

When re-entering the main loop of xenvif_tx_check_gop() a 2nd time, the
special considerations for the head of the SKB no longer apply. Don't
mistakenly report ERROR to the frontend for the first entry in the list,
even if - from all I can tell - this shouldn't matter much as the overall
transmit will need to be considered failed anyway.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Paul Durrant <paul@xen.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Vladimir Oltean says:

====================
Make DSA switch drivers compatible with masters which unregister on shutdown

Changes in v2:
- fix build for b53_mmap
- use unregister_netdevice_many

It was reported by Lino here:

https://lore.kernel.org/netdev/20210909095324.12978-1-LinoSanfilippo@gmx.de/

that when the DSA master attempts to unregister its net_device on
shutdown, DSA should prevent that operation from succeeding because it
holds a reference to it. This hangs the shutdown process.

This issue was essentially introduced in commit 2f1e8ea7 ("net: dsa:
link interfaces with the DSA master to get rid of lockdep warnings").
The present series patches all DSA drivers to handle that case,
depending on whether those drivers were introduced before or after the
offending commit, a different Fixes: tag is specified for them.

The approach taken by this series solves the issue in essentially the
same way as Lino's patches, except for three key differences:

- this series takes a more minimal approach in what is done on shutdown,
  we do not attempt a full tree teardown as that is not strictly
  necessary. I might revisit this if there are compelling reasons to do
  otherwise

- this series fixes the issues for all DSA drivers, not just KSZ9897

- this series works even if the ->remove driver method gets called for
  the same device too, not just ->shutdown. This is really possible to
  happen for SPI device drivers, and potentially possible for other bus
  device drivers too.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Since commit 2f1e8ea7 ("net: dsa: link interfaces with the DSA
master to get rid of lockdep warnings"), DSA gained a requirement which
it did not fulfill, which is to unlink itself from the DSA master at
shutdown time.

Since the Arrow SpeedChips XRS700x driver was introduced after the bad
commit, it has never worked with DSA masters which decide to unregister
their net_device on shutdown, effectively hanging the reboot process.
To fix that, we need to call dsa_switch_shutdown.

These devices can be connected by I2C or by MDIO, and if I search for
I2C or MDIO bus drivers that implement their ->shutdown by redirecting
it to ->remove I don't see any, however this does not mean it would not
be possible. To be compatible with that pattern, it is necessary to
implement an "if this then not that" scheme, to avoid ->remove and
->shutdown from being called both for the same struct device.

Fixes: ee00b24f ("net: dsa: add Arrow SpeedChips XRS700x driver")
Link: https://lore.kernel.org/netdev/20210909095324.12978-1-LinoSanfilippo@gmx.de/Reported-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: George McCollister <george.mccollister@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Since commit 2f1e8ea7 ("net: dsa: link interfaces with the DSA
master to get rid of lockdep warnings"), DSA gained a requirement which
it did not fulfill, which is to unlink itself from the DSA master at
shutdown time.

Since the Microchip sub-driver for KSZ8863 was introduced after the bad
commit, it has never worked with DSA masters which decide to unregister
their net_device on shutdown, effectively hanging the reboot process.
To fix that, we need to call dsa_switch_shutdown.

Since this driver expects the MDIO bus to be backed by mdio_bitbang, I
don't think there is currently any MDIO bus driver which implements its
->shutdown by redirecting it to ->remove, but in any case, to be
compatible with that pattern, it is necessary to implement an "if this
then not that" scheme, to avoid ->remove and ->shutdown from being
called both for the same struct device.

Fixes: 60a36476 ("net: dsa: microchip: Add Microchip KSZ8863 SMI based driver support")
Link: https://lore.kernel.org/netdev/20210909095324.12978-1-LinoSanfilippo@gmx.de/Reported-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
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>

Since commit 2f1e8ea7 ("net: dsa: link interfaces with the DSA
master to get rid of lockdep warnings"), DSA gained a requirement which
it did not fulfill, which is to unlink itself from the DSA master at
shutdown time.

Since the hellcreek driver was introduced after the bad commit, it has
never worked with DSA masters which decide to unregister their
net_device on shutdown, effectively hanging the reboot process.

Hellcreek is a platform device driver, so we probably cannot have the
oddities of ->shutdown and ->remove getting both called for the exact
same struct device. But to be in line with the pattern from the other
device drivers which are on slow buses, implement the same "if this then
not that" pattern of either running the ->shutdown or the ->remove hook.
The driver's current ->remove implementation makes that very easy
because it already zeroes out its device_drvdata on ->remove.

Fixes: e4b27ebc ("net: dsa: Add DSA driver for Hirschmann Hellcreek switches")
Link: https://lore.kernel.org/netdev/20210909095324.12978-1-LinoSanfilippo@gmx.de/Reported-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Acked-by: Kurt Kanzenbach <kurt@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

Lino reports that on his system with bcmgenet as DSA master and KSZ9897
as a switch, rebooting or shutting down never works properly.

What does the bcmgenet driver have special to trigger this, that other
DSA masters do not? It has an implementation of ->shutdown which simply
calls its ->remove implementation. Otherwise said, it unregisters its
network interface on shutdown.

This message can be seen in a loop, and it hangs the reboot process there:

unregister_netdevice: waiting for eth0 to become free. Usage count = 3

So why 3?

A usage count of 1 is normal for a registered network interface, and any
virtual interface which links itself as an upper of that will increment
it via dev_hold. In the case of DSA, this is the call path:

dsa_slave_create
-> netdev_upper_dev_link
   -> __netdev_upper_dev_link
      -> __netdev_adjacent_dev_insert
         -> dev_hold

So a DSA switch with 3 interfaces will result in a usage count elevated
by two, and netdev_wait_allrefs will wait until they have gone away.

Other stacked interfaces, like VLAN, watch NETDEV_UNREGISTER events and
delete themselves, but DSA cannot just vanish and go poof, at most it
can unbind itself from the switch devices, but that must happen strictly
earlier compared to when the DSA master unregisters its net_device, so
reacting on the NETDEV_UNREGISTER event is way too late.

It seems that it is a pretty established pattern to have a driver's
->shutdown hook redirect to its ->remove hook, so the same code is
executed regardless of whether the driver is unbound from the device, or
the system is just shutting down. As Florian puts it, it is quite a big
hammer for bcmgenet to unregister its net_device during shutdown, but
having a common code path with the driver unbind helps ensure it is well
tested.

So DSA, for better or for worse, has to live with that and engage in an
arms race of implementing the ->shutdown hook too, from all individual
drivers, and do something sane when paired with masters that unregister
their net_device there. The only sane thing to do, of course, is to
unlink from the master.

However, complications arise really quickly.

The pattern of redirecting ->shutdown to ->remove is not unique to
bcmgenet or even to net_device drivers. In fact, SPI controllers do it
too (see dspi_shutdown -> dspi_remove), and presumably, I2C controllers
and MDIO controllers do it too (this is something I have not researched
too deeply, but even if this is not the case today, it is certainly
plausible to happen in the future, and must be taken into consideration).

Since DSA switches might be SPI devices, I2C devices, MDIO devices, the
insane implication is that for the exact same DSA switch device, we
might have both ->shutdown and ->remove getting called.

So we need to do something with that insane environment. The pattern
I've come up with is "if this, then not that", so if either ->shutdown
or ->remove gets called, we set the device's drvdata to NULL, and in the
other hook, we check whether the drvdata is NULL and just do nothing.
This is probably not necessary for platform devices, just for devices on
buses, but I would really insist for consistency among drivers, because
when code is copy-pasted, it is not always copy-pasted from the best
sources.

So depending on whether the DSA switch's ->remove or ->shutdown will get
called first, we cannot really guarantee even for the same driver if
rebooting will result in the same code path on all platforms. But
nonetheless, we need to do something minimally reasonable on ->shutdown
too to fix the bug. Of course, the ->remove will do more (a full
teardown of the tree, with all data structures freed, and this is why
the bug was not caught for so long). The new ->shutdown method is kept
separate from dsa_unregister_switch not because we couldn't have
unregistered the switch, but simply in the interest of doing something
quick and to the point.

The big question is: does the DSA switch's ->shutdown get called earlier
than the DSA master's ->shutdown? If not, there is still a risk that we
might still trigger the WARN_ON in unregister_netdevice that says we are
attempting to unregister a net_device which has uppers. That's no good.
Although the reference to the master net_device won't physically go away
even if DSA's ->shutdown comes afterwards, remember we have a dev_hold
on it.

The answer to that question lies in this comment above device_link_add:

 * A side effect of the link creation is re-ordering of dpm_list and the
 * devices_kset list by moving the consumer device and all devices depending
 * on it to the ends of these lists (that does not happen to devices that have
 * not been registered when this function is called).

so the fact that DSA uses device_link_add towards its master is not
exactly for nothing. device_shutdown() walks devices_kset from the back,
so this is our guarantee that DSA's shutdown happens before the master's
shutdown.

Fixes: 2f1e8ea7 ("net: dsa: link interfaces with the DSA master to get rid of lockdep warnings")
Link: https://lore.kernel.org/netdev/20210909095324.12978-1-LinoSanfilippo@gmx.de/Reported-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Tested-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

MDIO-attached devices might have interrupts and other things that might
need quiesced when we kexec into a new kernel. Things are even more
creepy when those interrupt lines are shared, and in that case it is
absolutely mandatory to disable all interrupt sources.

Moreover, MDIO devices might be DSA switches, and DSA needs its own
shutdown method to unlink from the DSA master, which is a new
requirement that appeared after commit 2f1e8ea7 ("net: dsa: link
interfaces with the DSA master to get rid of lockdep warnings").

So introduce a ->shutdown method in the MDIO device driver structure.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

After d12e1c46 ("net: dsa: b53: Set correct number of ports in the
DSA struct") we stopped setting dsa_switch::num_ports to DSA_MAX_PORTS,
which created an off by one error between the statically allocated
bcm_sf2_priv::port_sts array (of size DSA_MAX_PORTS). When
dsa_is_cpu_port() is used, we end-up accessing an out of bounds member
and causing a NPD.

Fix this by iterating with the appropriate port count using
ds->num_ports.

Fixes: d12e1c46 ("net: dsa: b53: Set correct number of ports in the DSA struct")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

NXP Legal insists that the following are not fine:

- Saying "NXP Semiconductors" instead of "NXP", since the company's
  registered name is "NXP"

- Putting a "(c)" sign in the copyright string

- Putting a comma in the copyright string

The only accepted copyright string format is "Copyright <year-range> NXP".

This patch changes the copyright headers in the networking files that
were sent by me, or derived from code sent by me.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

If resource allocation and registration fail for a muxed tty device
(e.g. if there are no more minor numbers) the driver should not try to
deregister the never-registered (or already-deregistered) tty.

Fix up the error handling to avoid dereferencing a NULL pointer when
attempting to remove the character device.

Fixes: 72dc1c09 ("HSO: add option hso driver")
Cc: stable@vger.kernel.org	# 2.6.27
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Pull networking fixes from Jakub Kicinski:
 "Including fixes from bpf.

  Current release - regressions:

   - vhost_net: fix OoB on sendmsg() failure

   - mlx5: bridge, fix uninitialized variable usage

   - bnxt_en: fix error recovery regression

  Current release - new code bugs:

   - bpf, mm: fix lockdep warning triggered by stack_map_get_build_id_offset()

  Previous releases - regressions:

   - r6040: restore MDIO clock frequency after MAC reset

   - tcp: fix tp->undo_retrans accounting in tcp_sacktag_one()

   - dsa: flush switchdev workqueue before tearing down CPU/DSA ports

  Previous releases - always broken:

   - ptp: dp83640: don't define PAGE0, avoid compiler warning

   - igc: fix tunnel segmentation offloads

   - phylink: update SFP selected interface on advertising changes

   - stmmac: fix system hang caused by eee_ctrl_timer during suspend/resume

   - mlx5e: fix mutual exclusion between CQE compression and HW TS

  Misc:

   - bpf, cgroups: fix cgroup v2 fallback on v1/v2 mixed mode

   - sfc: fallback for lack of xdp tx queues

   - hns3: add option to turn off page pool feature"

* tag 'net-5.15-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (67 commits)
  mlxbf_gige: clear valid_polarity upon open
  igc: fix tunnel offloading
  net/{mlx5|nfp|bnxt}: Remove unnecessary RTNL lock assert
  net: wan: wanxl: define CROSS_COMPILE_M68K
  selftests: nci: replace unsigned int with int
  net: dsa: flush switchdev workqueue before tearing down CPU/DSA ports
  Revert "net: phy: Uniform PHY driver access"
  net: dsa: destroy the phylink instance on any error in dsa_slave_phy_setup
  ptp: dp83640: don't define PAGE0
  bnx2x: Fix enabling network interfaces without VFs
  Revert "Revert "ipv4: fix memory leaks in ip_cmsg_send() callers""
  tcp: fix tp->undo_retrans accounting in tcp_sacktag_one()
  net-caif: avoid user-triggerable WARN_ON(1)
  bpf, selftests: Add test case for mixed cgroup v1/v2
  bpf, selftests: Add cgroup v1 net_cls classid helpers
  bpf, cgroups: Fix cgroup v2 fallback on v1/v2 mixed mode
  bpf: Add oversize check before call kvcalloc()
  net: hns3: fix the timing issue of VF clearing interrupt sources
  net: hns3: fix the exception when query imp info
  net: hns3: disable mac in flr process
  ...

tx timeout and slot time are currently specified in units of HZ.  On
Alpha, HZ is defined as 1024.  When building alpha:allmodconfig, this
results in the following error message.

  drivers/net/hamradio/6pack.c: In function 'sixpack_open':
  drivers/net/hamradio/6pack.c:71:41: error:
  	unsigned conversion from 'int' to 'unsigned char'
  	changes value from '256' to '0'

In the 6PACK protocol, tx timeout is specified in units of 10 ms and
transmitted over the wire:

    https://www.linux-ax25.org/wiki/6PACK

Defining a value dependent on HZ doesn't really make sense, and
presumably comes from the (very historical) situation where HZ was
originally 100.

Note that the SIXP_SLOTTIME use explicitly is about 10ms granularity:

        mod_timer(&sp->tx_t, jiffies + ((when + 1) * HZ) / 100);

and the SIXP_TXDELAY walue is sent as a byte over the wire.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

With the new static annotation, the compiler warns when the functions
are actually unused:

   drivers/gpu/drm/rockchip/cdn-dp-core.c:1123:12: error: 'cdn_dp_resume' defined but not used [-Werror=unused-function]
    1123 | static int cdn_dp_resume(struct device *dev)
         |            ^~~~~~~~~~~~~

Mark them __maybe_unused to suppress that warning as well.

[ Not so 'new' static annotations any more, and I removed the part of
  the patch that added __maybe_unused to cdn_dp_suspend(), because it's
  used by the shutdown/remove code.

  So only the resume function ends up possibly unused if CONFIG_PM isn't
  set     - Linus ]

Fixes: 7c49abb4 ("drm/rockchip: cdn-dp-core: Make cdn_dp_core_suspend/resume static")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arm:allmodconfig fails to build with the following error.

  drivers/cpufreq/vexpress-spc-cpufreq.c:454:13: error:
					unused variable 'cur_cluster'

Remove the unused variable.

Fixes: bb8c26d9 ("cpufreq: vexpress: Set CPUFREQ_IS_COOLING_DEV flag")
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Some drivers pass a pointer to volatile data to virt_to_bus() and
virt_to_phys(), and that works fine.  One exception is alpha.  This
results in a number of compile errors such as

  drivers/net/wan/lmc/lmc_main.c: In function 'lmc_softreset':
  drivers/net/wan/lmc/lmc_main.c:1782:50: error:
	passing argument 1 of 'virt_to_bus' discards 'volatile'
	qualifier from pointer target type

  drivers/atm/ambassador.c: In function 'do_loader_command':
  drivers/atm/ambassador.c:1747:58: error:
	passing argument 1 of 'virt_to_bus' discards 'volatile'
	qualifier from pointer target type

Declare the parameter of virt_to_phys and virt_to_bus as pointer to
volatile to fix the problem.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

This driver isn't enabled most places because of the ISA config
dependency, but alpha still has it.  And I think the 'Jensen' actually
did have an ISA slot.

However, it doesn't build cleanly, because the "Vortex bus master" code
just casts the skb->data pointer to 'int':

        outl((int) (skb->data), ioaddr + Wn7_MasterAddr);

which is all kinds of broken.  Even on a good old traditional PC/AT it
would be broken because the high bits will be random kernel address
bits, but presumably the hardware ignores those bits.  I mean, it's ISA.
We're talking 16MB dma limits. The "good old days".

Make the build happy with this kind of craziness by using the proper
isa_virt_to_bus() handling that the full bus master code uses anyway
(the Vortex bus mastering is a limited special case).

Who knows, this might even work.
Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull parisc fix from Helge Deller:
 "Fix a build warning when using the PAGE0 pointer"

* tag 'for-5.15/parisc-4' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
  parisc: Use absolute_pointer() to define PAGE0

Pull m68k fixes from Geert Uytterhoeven:

 - Warning fixes to mitigate CONFIG_WERROR=y

* tag 'm68k-for-v5.15-tag2' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k:
  m68k: mvme: Remove overdue #warnings in RTC handling
  m68k: Double cast io functions to unsigned long

The network interface managed by the mlxbf_gige driver can
get into a problem state where traffic does not flow.
In this state, the interface will be up and enabled, but
will stop processing received packets.  This problem state
will happen if three specific conditions occur:
    1) driver has received more than (N * RxRingSize) packets but
       less than (N+1 * RxRingSize) packets, where N is an odd number
       Note: the command "ethtool -g <interface>" will display the
       current receive ring size, which currently defaults to 128
    2) the driver's interface was disabled via "ifconfig oob_net0 down"
       during the window described in #1.
    3) the driver's interface is re-enabled via "ifconfig oob_net0 up"

This patch ensures that the driver's "valid_polarity" field is
cleared during the open() method so that it always matches the
receive polarity used by hardware.  Without this fix, the driver
needs to be unloaded and reloaded to correct this problem state.

Fixes: f92e1869 ("Add Mellanox BlueField Gigabit Ethernet driver")
Reviewed-by: Asmaa Mnebhi <asmaa@nvidia.com>
Signed-off-by: David Thompson <davthompson@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Checking tunnel offloading, it turns out that offloading doesn't work
as expected.  The following script allows to reproduce the issue.
Call it as `testscript DEVICE LOCALIP REMOTEIP NETMASK'

=== SNIP ===
if [ $# -ne 4 ]
then
  echo "Usage $0 DEVICE LOCALIP REMOTEIP NETMASK"
  exit 1
fi
DEVICE="$1"
LOCAL_ADDRESS="$2"
REMOTE_ADDRESS="$3"
NWMASK="$4"
echo "Driver: $(ethtool -i ${DEVICE} | awk '/^driver:/{print $2}') "
ethtool -k "${DEVICE}" | grep tx-udp
echo
echo "Set up NIC and tunnel..."
ip addr add "${LOCAL_ADDRESS}/${NWMASK}" dev "${DEVICE}"
ip link set "${DEVICE}" up
sleep 2
ip link add vxlan1 type vxlan id 42 \
		   remote "${REMOTE_ADDRESS}" \
		   local "${LOCAL_ADDRESS}" \
		   dstport 0 \
		   dev "${DEVICE}"
ip addr add fc00::1/64 dev vxlan1
ip link set vxlan1 up
sleep 2
rm -f vxlan.pcap
echo "Running tcpdump and iperf3..."
( nohup tcpdump -i any -w vxlan.pcap >/dev/null 2>&1 ) &
sleep 2
iperf3 -c fc00::2 >/dev/null
pkill tcpdump
echo
echo -n "Max. Paket Size: "
tcpdump -r vxlan.pcap -nnle 2>/dev/null \
| grep "${LOCAL_ADDRESS}.*> ${REMOTE_ADDRESS}.*OTV" \
| awk '{print $8}' | awk -F ':' '{print $1}' \
| sort -n | tail -1
echo
ip link del vxlan1
ip addr del ${LOCAL_ADDRESS}/${NWMASK} dev "${DEVICE}"
=== SNAP ===

The expected outcome is

  Max. Paket Size: 64904

This is what you see on igb, the code igc has been taken from.
However, on igc the output is

  Max. Paket Size: 1516

so the GSO aggregate packets are segmented by the kernel before calling
igc_xmit_frame.  Inside the subsequent call to igc_tso, the check for
skb_is_gso(skb) fails and the function returns prematurely.

It turns out that this occurs because the feature flags aren't set
entirely correctly in igc_probe.  In contrast to the original code
from igb_probe, igc_probe neglects to set the flags required to allow
tunnel offloading.

Setting the same flags as igb fixes the issue on igc.

Fixes: 34428dff ("igc: Add GSO partial support")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Tested-by: Corinna Vinschen <vinschen@redhat.com>
Acked-by: Sasha Neftin <sasha.neftin@intel.com>
Tested-by: Nechama Kraus <nechamax.kraus@linux.intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Remove the assert from the callback priv lookup function since it does
not require RTNL lock and is already protected by flow_indr_block_lock.

This will avoid warnings from being emitted to dmesg if the driver
registers its callback after an ingress qdisc was created for a
netdevice.

The warnings started after the following patch was merged:
commit 74fc4f82 ("net: Fix offloading indirect devices dependency on qdisc order creation")
Signed-off-by: Eli Cohen <elic@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

It was used but never set.  The hardcoded value from before the dawn of
time was non-standard; the usual name for cross-tools is $TRIPLET-$TOOL
Signed-off-by: Adam Borowski <kilobyte@angband.pl>
Signed-off-by: David S. Miller <davem@davemloft.net>

Should not use comparison of unsigned expressions < 0.
Signed-off-by: Xiang wangx <wangxiang@cdjrlc.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Use absolute_pointer() wrapper for PAGE0 to avoid this compiler warning:

  arch/parisc/kernel/setup.c: In function 'start_parisc':
  error: '__builtin_memcmp_eq' specified bound 8 exceeds source size 0
Signed-off-by: Helge Deller <deller@gmx.de>
Co-Developed-by: Guenter Roeck <linux@roeck-us.net>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>

Merge tag 'hyperv-fixes-signed-20210915' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux

Pull hyperv fixes from Wei Liu:

 - Fix kernel crash caused by uio driver (Vitaly Kuznetsov)

 - Remove on-stack cpumask from HV APIC code (Wei Liu)

* tag 'hyperv-fixes-signed-20210915' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux:
  x86/hyperv: remove on-stack cpumask from hv_send_ipi_mask_allbutself
  asm-generic/hyperv: provide cpumask_to_vpset_noself
  Drivers: hv: vmbus: Fix kernel crash upon unbinding a device from uio_hv_generic driver

Pull RTC fix from Alexandre Belloni:
 "Fix a locking issue in the cmos rtc driver"

* tag 'rtc-5.15-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux:
  rtc: cmos: Disable irq around direct invocation of cmos_interrupt()