Instead of preemption disable/enable to reflect the purpose. This allows
PREEMPT_RT to substitute it with an actual migration disable
implementation. On non RT kernels this is still mapped to
preempt_disable/enable().
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200224145643.891428873@linutronix.de
Replace the preemption disable/enable with migrate_disable/enable() to
reflect the actual requirement and to allow PREEMPT_RT to substitute it
with an actual migration disable mechanism which does not disable
preemption.
[ tglx: Switched it over to migrate disable ]
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200224145643.785306549@linutronix.de
All of these cases are strictly of the form:
preempt_disable();
BPF_PROG_RUN(...);
preempt_enable();
Replace this with bpf_prog_run_pin_on_cpu() which wraps BPF_PROG_RUN()
with:
migrate_disable();
BPF_PROG_RUN(...);
migrate_enable();
On non RT enabled kernels this maps to preempt_disable/enable() and on RT
enabled kernels this solely prevents migration, which is sufficient as
there is no requirement to prevent reentrancy to any BPF program from a
preempting task. The only requirement is that the program stays on the same
CPU.
Therefore, this is a trivially correct transformation.
The seccomp loop does not need protection over the loop. It only needs
protection per BPF filter program
[ tglx: Converted to bpf_prog_run_pin_on_cpu() ]
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200224145643.691493094@linutronix.de
As already discussed in the previous change which introduced
BPF_RUN_PROG_PIN_ON_CPU() BPF only requires to disable migration to
guarantee per CPUness.
If RT substitutes the preempt disable based migration protection then the
cant_sleep() check will obviously trigger as preemption is not disabled.
Replace it by cant_migrate() which maps to cant_sleep() on a non RT kernel
and will verify that migration is disabled on a full RT kernel.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200224145643.583038889@linutronix.de
BPF programs require to run on one CPU to completion as they use per CPU
storage, but according to Alexei they don't need reentrancy protection as
obviously BPF programs running in thread context can always be 'preempted'
by hard and soft interrupts and instrumentation and the same program can
run concurrently on a different CPU.
The currently used mechanism to ensure CPUness is to wrap the invocation
into a preempt_disable/enable() pair. Disabling preemption is also
disabling migration for a task.
preempt_disable/enable() is used because there is no explicit way to
reliably disable only migration.
Provide a separate macro to invoke a BPF program which can be used in
migrateable task context.
It wraps BPF_PROG_RUN() in a migrate_disable/enable() pair which maps on
non RT enabled kernels to preempt_disable/enable(). On RT enabled kernels
this merely disables migration. Both methods ensure that the invoked BPF
program runs on one CPU to completion.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200224145643.474592620@linutronix.de
pcpu_freelist_populate() is disabling interrupts and then iterates over the
possible CPUs. The reason why this disables interrupts is to silence
lockdep because the invoked ___pcpu_freelist_push() takes spin locks.
Neither the interrupt disabling nor the locking are required in this
function because it's called during initialization and the resulting map is
not yet visible to anything.
Split out the actual push assignement into an inline, call it from the loop
and remove the interrupt disable.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200224145643.365930116@linutronix.de
If an element is freed via RCU then recursion into BPF instrumentation
functions is not a concern. The element is already detached from the map
and the RCU callback does not hold any locks on which a kprobe, perf event
or tracepoint attached BPF program could deadlock.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200224145643.259118710@linutronix.de
The BPF invocation from the perf event overflow handler does not require to
disable preemption because this is called from NMI or at least hard
interrupt context which is already non-preemptible.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200224145643.151953573@linutronix.de
Similar to __bpf_trace_run this is redundant because __bpf_trace_run() is
invoked from a trace point via __DO_TRACE() which already disables
preemption _before_ invoking any of the functions which are attached to a
trace point.
Remove it and add a cant_sleep() check.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200224145643.059995527@linutronix.de
trace_call_bpf() no longer disables preemption on its own.
All callers of this function has to do it explicitly.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
All callers are built in. No point to export this.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
__bpf_trace_run() disables preemption around the BPF_PROG_RUN() invocation.
This is redundant because __bpf_trace_run() is invoked from a trace point
via __DO_TRACE() which already disables preemption _before_ invoking any of
the functions which are attached to a trace point.
Remove it and add a cant_sleep() check.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200224145642.847220186@linutronix.de
The comment where the bucket lock is acquired says:
/* bpf_map_update_elem() can be called in_irq() */
which is not really helpful and aside of that it does not explain the
subtle details of the hash bucket locks expecially in the context of BPF
and perf, kprobes and tracing.
Add a comment at the top of the file which explains the protection scopes
and the details how potential deadlocks are prevented.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200224145642.755793061@linutronix.de
Aside of the general unsafety of run-time map allocation for
instrumentation type programs RT enabled kernels have another constraint:
The instrumentation programs are invoked with preemption disabled, but the
memory allocator spinlocks cannot be acquired in atomic context because
they are converted to 'sleeping' spinlocks on RT.
Therefore enforce map preallocation for these programs types when RT is
enabled.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200224145642.648784007@linutronix.de
The assumption that only programs attached to perf NMI events can deadlock
on memory allocators is wrong. Assume the following simplified callchain:
kmalloc() from regular non BPF context
cache empty
freelist empty
lock(zone->lock);
tracepoint or kprobe
BPF()
update_elem()
lock(bucket)
kmalloc()
cache empty
freelist empty
lock(zone->lock); <- DEADLOCK
There are other ways which do not involve locking to create wreckage:
kmalloc() from regular non BPF context
local_irq_save();
...
obj = slab_first();
kprobe()
BPF()
update_elem()
lock(bucket)
kmalloc()
local_irq_save();
...
obj = slab_first(); <- Same object as above ...
So preallocation _must_ be enforced for all variants of intrusive
instrumentation.
Unfortunately immediate enforcement would break backwards compatibility, so
for now such programs still are allowed to run, but a one time warning is
emitted in dmesg and the verifier emits a warning in the verifier log as
well so developers are made aware about this and can fix their programs
before the enforcement becomes mandatory.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200224145642.540542802@linutronix.de
* remove a double mutex-unlock
* fix a leak in an error path
* NULL pointer check
* include if_vlan.h where needed
* avoid RCU list traversal when not under RCU
-----BEGIN PGP SIGNATURE-----
iQIzBAABCgAdFiEEH1e1rEeCd0AIMq6MB8qZga/fl8QFAl5UGA8ACgkQB8qZga/f
l8Qk4g/8DstHoC7R74x4jrOyGffw7ss7XC8YJi2x3IENg7mAYdEFvnUC7GQmrCso
aMypkOWac0H4cAw2BId8CFevbWZbanJ9uvC4JicQpaNa9bZkqBaDMFwO3k66S1hA
JBvmOqPy8FNuFRsXTicMPw7/I6QazR+sW7Ed68L7ygikkklvTeovH9qkL+zHHMcK
dAVS6ZKB2jSkEOtnlG01QMRwdIijTkD6KjGDECVMzau9XC+fGowQeuy+xuAU0THq
Myef9CpzU2Q47Sa61fEyXVC54Izp9B1ZuohM2wfrN2zC3SKxsmPM1lm4GhrJOfUF
wJTQY75z1kAmCAJDKpwBrFkyIEfUPQV1v9HHit0LX4y11NYNWL22liLhPv+kZDmD
9ht1IxAP1Nw/DSVKaXUmwk1tFkETfk2BvCkNjVrwKlt88QgvQAL/uzgKoz5E6VIM
hU1hp0mJCzsmyt/COWOf0l/QpO2nN3/64YHZgFiqOGnhXr5r0L74Jf3lcdWyaXRU
hcJ0M/EcfGLWOlHFcRkNdWCkBFk5Daf4/zzQ3vO9weAlb7wOLDo9mHoXMBgP6R9l
kCnxjxgIqmpQLvMo/sBt2cLaf3bJU40p/BYU7hqI7CerODFc3JKkCs1ODZPbYDaR
Fk60mlElkBD3P4EU8/6nbXHOfG9FvEiZjhT7kRcUdPx0dLA/KMk=
=7JH4
-----END PGP SIGNATURE-----
Merge tag 'mac80211-for-net-2020-02-24' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211
Johannes Berg
====================
A few fixes:
* remove a double mutex-unlock
* fix a leak in an error path
* NULL pointer check
* include if_vlan.h where needed
* avoid RCU list traversal when not under RCU
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
* lots of small documentation fixes, from Jérôme Pouiller
* beacon protection (BIGTK) support from Jouni Malinen
* some initial code for TID configuration, from Tamizh chelvam
* I reverted some new API before it's actually used, because
it's wrong to mix controlled port and preauth
* a few other cleanups/fixes
-----BEGIN PGP SIGNATURE-----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=x0rf
-----END PGP SIGNATURE-----
Merge tag 'mac80211-next-for-net-next-2020-02-24' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211-next
Johannes Berg says:
====================
A new set of changes:
* lots of small documentation fixes, from Jérôme Pouiller
* beacon protection (BIGTK) support from Jouni Malinen
* some initial code for TID configuration, from Tamizh chelvam
* I reverted some new API before it's actually used, because
it's wrong to mix controlled port and preauth
* a few other cleanups/fixes
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
There is a spelling mistake in a pr_err message. Fix it.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The "stm32_pwr_wakeup" is optional per the binding and the driver
handles its absence gracefully. Request it with
platform_get_irq_byname_optional, so its absence doesn't needlessly
clutter the log.
Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
The specification of a "eth-ck" and a "ptp_ref" clock is optional per
the binding and the driver handles them gracefully.
Demote the output to an info message accordingly.
Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Jeremy Linton says:
====================
Add ACPI bindings to the genet
This patch series allows the BCM GENET, as used on the RPi4,
to attach when booted in an ACPI environment. The DSDT entry to
trigger this is seen below. Of note, the first patch adds a
small extension to the mdio layer which allows drivers to find
the mii_bus without firmware assistance. The fifth patch in
the set retrieves the MAC address from the umac registers
rather than carrying it directly in the DSDT. This of course
requires the firmware to pre-program it, so we continue to fall
back on a random one if it appears to be garbage.
v1 -> v2:
fail on missing phy-mode property
replace phy-mode internal property read string with
device_get_phy_mode() equivalent
rework mac address detection logic so that it merges
the acpi/DT case into device_get_mac_address()
allowing _DSD mac address properties.
some commit messages justifying why phy_find_first()
isn't the worst choice for this driver.
+ Device (ETH0)
+ {
+ Name (_HID, "BCM6E4E")
+ Name (_UID, 0)
+ Name (_CCA, 0x0)
+ Method (_STA)
+ {
+ Return (0xf)
+ }
+ Method (_CRS, 0x0, Serialized)
+ {
+ Name (RBUF, ResourceTemplate ()
+ {
+ Memory32Fixed (ReadWrite, 0xFd580000, 0x10000, )
+ Interrupt (ResourceConsumer, Level, ActiveHigh, Exclusive) { 0xBD }
+ Interrupt (ResourceConsumer, Level, ActiveHigh, Exclusive) { 0xBE }
+ })
+ Return (RBUF)
+ }
+ Name (_DSD, Package () {
+ ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
+ Package () {
+ Package () { "phy-mode", "rgmii-rxid" },
+ }
+ })
+ }
====================
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If one types "failed to get enet clock" or similar into google
there are ~370k hits. The vast majority are people debugging
problems unrelated to this adapter, or bragging about their
rpi's. Further, the DT clock bindings here are optional.
Given that its not a fatal situation with common DT based
systems, lets reduce the severity so people aren't seeing failure
messages in everyday operation.
Signed-off-by: Jeremy Linton <jeremy.linton@arm.com>
Reviewed-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
ARM/ACPI machines should utilize self describing hardware
when possible. The MAC address on the BCMGENET can be
read from the adapter if a full featured firmware has already
programmed it. Lets try using the address already programmed,
if it appears to be valid.
It should be noted that while we move the macaddr logic below
the clock and power logic in the driver, none of that code will
ever be active in an ACPI environment as the device will be
attached to the acpi power domain, and brought to full power
with all clocks enabled immediately before the device probe
routine is called.
One side effect of the above tweak is that while its now
possible to read the MAC address via _DSD properties, it should
be avoided.
Signed-off-by: Jeremy Linton <jeremy.linton@arm.com>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The rpi4 is capable of booting in ACPI mode with the latest
edk2-platform commits. As such it would be helpful if the genet
platform device were usable.
To achieve this we add a new MODULE_DEVICE_TABLE, and convert
a few dt specific methods to their generic device_ calls. Until
the next patch, ACPI based machines will fallback on random
mac addresses.
Signed-off-by: Jeremy Linton <jeremy.linton@arm.com>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The unimac mdio driver falls back to scanning the
entire bus if its given an appropriate mask. In ACPI
mode we expect that the system is well behaved and
conforms to recent versions of the specification.
We then utilize phy_find_first(), and
phy_connect_direct() to find and attach to the
discovered phy during net_device open. While its
apparently possible to build a genet based device
with multiple phys on a single mdio bus, this works
for current machines. Further, this driver makes
a number of assumptions about the platform device,
mac, mdio and phy all being 1:1. Lastly, It also
avoids having to create references across the ACPI
namespace hierarchy.
Signed-off-by: Jeremy Linton <jeremy.linton@arm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The DT phy mode is similar to what we want for ACPI
lets factor it out of the of path, and change the
of_ call to device_.
Signed-off-by: Jeremy Linton <jeremy.linton@arm.com>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
It appears most ethernet drivers follow one of two main strategies
for mdio bus/phy management. A monolithic model where the net driver
itself creates, probes and uses the phy, and one where an external
mdio/phy driver instantiates the mdio bus/phy and the net driver
only attaches to a known phy. Usually in this latter model the phys
are discovered via DT relationships or simply phy name/address
hardcoding.
This is a shame because modern well behaved mdio buses are self
describing and can be probed. The mdio layer itself is fully capable
of this, yet there isn't a clean way for a standalone net driver
to attach and enumerate the discovered devices. This is because
outside of of_mdio_find_bus() there isn't a straightforward way
to acquire the mii_bus pointer.
So, lets add a mdio_find_bus which can return the mii_bus based
only on its name.
Signed-off-by: Jeremy Linton <jeremy.linton@arm.com>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Vladimir Oltean says:
====================
Remainder for "DT bindings for Felix DSA switch on LS1028A"
This series is the remainder of patchset [0] which has been merged
through Shawn Guo's devicetree tree.
It contains changes to the PHY mode validation in the Felix driver
("gmii" to "internal") and the documentation for the DT bindings.
[0]: https://patchwork.ozlabs.org/cover/1242716/
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds the required documentation for the embedded L2 switch
inside the NXP LS1028A chip.
I've submitted it in the legacy format instead of yaml schema, because
DSA itself has not yet been converted to yaml, and this driver defines
no custom bindings.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
phy-mode = "gmii" is confusing because it may mean that the port
supports the 8-bit-wide parallel data interface pinout, which it
doesn't.
It may also be confusing because one of the "gmii" internal ports is
actually overclocked to run at 2.5Gbps (even though, yes, as far as the
switch MAC is concerned, it still thinks it's gigabit).
So use the phy-mode = "internal" property to describe the internal ports
inside the NXP LS1028A chip (the ones facing the ENETC). The change
should be fine, because the device tree bindings document is yet to be
introduced, and there are no stable DT blobs in use.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Tested-by: Michael Walle <michael@walle.cc>
Signed-off-by: David S. Miller <davem@davemloft.net>
drivers/net/bareudp.c: In function 'bareudp_xmit_skb':
drivers/net/bareudp.c:346:9: warning: 'err' may be used uninitialized in this function [-Wmaybe-uninitialized]
346 | return err;
| ^~~
drivers/net/bareudp.c: In function 'bareudp6_xmit_skb':
drivers/net/bareudp.c:407:9: warning: 'err' may be used uninitialized in this function [-Wmaybe-uninitialized]
407 | return err;
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Martin Varghese says:
====================
Bare UDP L3 Encapsulation Module
There are various L3 encapsulation standards using UDP being discussed to
leverage the UDP based load balancing capability of different networks.
MPLSoUDP (__ https://tools.ietf.org/html/rfc7510) is one among them.
The Bareudp tunnel module provides a generic L3 encapsulation tunnelling
support for tunnelling different L3 protocols like MPLS, IP, NSH etc. inside
a UDP tunnel.
Special Handling
----------------
The bareudp device supports special handling for MPLS & IP as they can have
multiple ethertypes.
MPLS procotcol can have ethertypes ETH_P_MPLS_UC (unicast) & ETH_P_MPLS_MC (multicast).
IP protocol can have ethertypes ETH_P_IP (v4) & ETH_P_IPV6 (v6).
This special handling can be enabled only for ethertypes ETH_P_IP & ETH_P_MPLS_UC
with a flag called multiproto mode.
Usage
------
1) Device creation & deletion
a) ip link add dev bareudp0 type bareudp dstport 6635 ethertype 0x8847.
This creates a bareudp tunnel device which tunnels L3 traffic with ethertype
0x8847 (MPLS traffic). The destination port of the UDP header will be set to
6635.The device will listen on UDP port 6635 to receive traffic.
b) ip link delete bareudp0
2) Device creation with multiple proto mode enabled
There are two ways to create a bareudp device for MPLS & IP with multiproto mode
enabled.
a) ip link add dev bareudp0 type bareudp dstport 6635 ethertype 0x8847 multiproto
b) ip link add dev bareudp0 type bareudp dstport 6635 ethertype mpls
3) Device Usage
The bareudp device could be used along with OVS or flower filter in TC.
The OVS or TC flower layer must set the tunnel information in SKB dst field before
sending packet buffer to the bareudp device for transmission. On reception the
bareudp device extracts and stores the tunnel information in SKB dst field before
passing the packet buffer to the network stack.
Why not FOU ?
------------
FOU by design does l4 encapsulation.It maps udp port to ipproto (IP protocol number for l4 protocol).
Bareudp acheives a generic l3 encapsulation.It maps udp port to l3 ethertype.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Special handling is needed in bareudp module for IP & MPLS as they
support more than one ethertypes.
MPLS has 2 ethertypes. 0x8847 for MPLS unicast and 0x8848 for MPLS multicast.
While decapsulating MPLS packet from UDP packet the tunnel destination IP
address is checked to determine the ethertype. The ethertype of the packet
will be set to 0x8848 if the tunnel destination IP address is a multicast
IP address. The ethertype of the packet will be set to 0x8847 if the
tunnel destination IP address is a unicast IP address.
IP has 2 ethertypes.0x0800 for IPV4 and 0x86dd for IPv6. The version
field of the IP header tunnelled will be checked to determine the ethertype.
This special handling to tunnel additional ethertypes will be disabled
by default and can be enabled using a flag called multiproto. This flag can
be used only with ethertypes 0x8847 and 0x0800.
Signed-off-by: Martin Varghese <martin.varghese@nokia.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The Bareudp tunnel module provides a generic L3 encapsulation
tunnelling module for tunnelling different protocols like MPLS,
IP,NSH etc inside a UDP tunnel.
Signed-off-by: Martin Varghese <martin.varghese@nokia.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Sparse reports a warning unix_wait_for_peer()
warning: context imbalance in unix_wait_for_peer() - unexpected unlock
The root cause is the missing annotation at unix_wait_for_peer()
Add the missing annotation __releases(&unix_sk(other)->lock)
Signed-off-by: Jules Irenge <jbi.octave@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Sparse reports a warning at dccp_child_process()
warning: context imbalance in dccp_child_process() - unexpected unlock
The root cause is the missing annotation at dccp_child_process()
Add the missing __releases(child) annotation
Signed-off-by: Jules Irenge <jbi.octave@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Sparse reports a warning at nr_neigh_stop()
warning: context imbalance in nr_neigh_stop() - unexpected unlock
The root cause is the missing annotation at nr_neigh_stop()
Add the missing __releases(&nr_neigh_list_lock) annotation
Signed-off-by: Jules Irenge <jbi.octave@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Sparse reports a warning at nr_neigh_start()
warning: context imbalance in nr_neigh_start() - wrong count at exit
The root cause is the missing annotation at nr_neigh_start()
Add the missing __acquires(&nr_neigh_list_lock) annotation
Signed-off-by: Jules Irenge <jbi.octave@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Sparse reports a warning at nr_node_stop()
warning: context imbalance in nr_node_stop() - wrong count at exit
The root cause is the missing annotation at nr_node_stop()
Add the missing __releases(&nr_node_list_lock) annotation
Signed-off-by: Jules Irenge <jbi.octave@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Sparse reports a warning at nr_node_start()
warning: context imbalance in nr_node_start() - wrong count at exit
The root cause is the missing annotation at nr_node_start()
Add the missing __acquires(&nr_node_list_lock) annotation
Signed-off-by: Jules Irenge <jbi.octave@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Sparse reports a warning at nr_info_stop()
warning: context imbalance in nr_info_stop() - unexpected unlock
The root cause is the missing annotation at nr_info_stop()
Add the missing __releases(&nr_list_lock)
Signed-off-by: Jules Irenge <jbi.octave@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Sparse reports a warning at nr_info_start()
warning: context imbalance in nr_info_start() - wrong count at exit
The root cause is the missing annotation at nr_info_start()
Add the missing __acquires(&nr_list_lock)
Signed-off-by: Jules Irenge <jbi.octave@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Sparse reports a warning at llc_seq_start()
warning: context imbalance in llc_seq_start() - wrong count at exit
The root cause is the msiing annotation at llc_seq_start()
Add the missing __acquires(RCU) annotation
Signed-off-by: Jules Irenge <jbi.octave@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Sparse reports a warning at sctp_transport_walk_stop()
warning: context imbalance in sctp_transport_walk_stop
- wrong count at exit
The root cause is the missing annotation at sctp_transport_walk_stop()
Add the missing __releases(RCU) annotation
Signed-off-by: Jules Irenge <jbi.octave@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
