Currently, if there are multiple registrations of the same pin on the
same dpll device, following warnings are observed:
WARNING: CPU: 5 PID: 2212 at drivers/dpll/dpll_core.c:143 dpll_xa_ref_pin_del.isra.0+0x21e/0x230
WARNING: CPU: 5 PID: 2212 at drivers/dpll/dpll_core.c:223 __dpll_pin_unregister+0x2b3/0x2c0
The problem is, that in both dpll_xa_ref_dpll_del() and
dpll_xa_ref_pin_del() registration is only removed from list in case the
reference count drops to zero. That is wrong, the registration has to
be removed always.
To fix this, remove the registration from the list and free
it unconditionally, instead of doing it only when the ref reference
counter reaches zero.
Fixes: 9431063ad3 ("dpll: core: Add DPLL framework base functions")
Signed-off-by: Jiri Pirko <jiri@nvidia.com>
Reviewed-by: Rahul Rameshbabu <rrameshbabu@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Older versions of GCC really want to know the full definition
of the type involved in rcu_assign_pointer().
struct dpll_pin is defined in a local header, net/core can't
reach it. Move all the netdev <> dpll code into dpll, where
the type is known. Otherwise we'd need multiple function calls
to jump between the compilation units.
This is the same problem the commit under fixes was trying to address,
but with rcu_assign_pointer() not rcu_dereference().
Some of the exports are not needed, networking core can't
be a module, we only need exports for the helpers used by
drivers.
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: https://lore.kernel.org/all/35a869c8-52e8-177-1d4d-e57578b99b6@linux-m68k.org/
Fixes: 640f41ed33 ("dpll: fix build failure due to rcu_dereference_check() on unknown type")
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20240305013532.694866-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Tasmiya reports that their compiler complains that we deref
a pointer to unknown type with rcu_dereference_rtnl():
include/linux/rcupdate.h:439:9: error: dereferencing pointer to incomplete type ‘struct dpll_pin’
Unclear what compiler it is, at the moment, and we can't report
but since DPLL can't be a module - move the code from the header
into the source file.
Fixes: 0d60d8df6f ("dpll: rely on rcu for netdev_dpll_pin()")
Reported-by: Tasmiya Nalatwad <tasmiya@linux.vnet.ibm.com>
Link: https://lore.kernel.org/all/3fcf3a2c-1c1b-42c1-bacb-78fdcd700389@linux.vnet.ibm.com/
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20240229190515.2740221-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This fixes a possible UAF in if_nlmsg_size(),
which can run without RTNL.
Add rcu protection to "struct dpll_pin"
Move netdev_dpll_pin() from netdevice.h to dpll.h to
decrease name pollution.
Note: This looks possible to no longer acquire RTNL in
netdev_dpll_pin_assign() later in net-next.
v2: do not force rcu_read_lock() in rtnl_dpll_pin_size() (Jiri Pirko)
Fixes: 5f18426928 ("netdev: expose DPLL pin handle for netdevice")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Arkadiusz Kubalewski <arkadiusz.kubalewski@intel.com>
Cc: Vadim Fedorenko <vadim.fedorenko@linux.dev>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Link: https://lore.kernel.org/r/20240223123208.3543319-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Recently, I've been hitting following deadlock warning during dpll pin
dump:
[52804.637962] ======================================================
[52804.638536] WARNING: possible circular locking dependency detected
[52804.639111] 6.8.0-rc2jiri+ #1 Not tainted
[52804.639529] ------------------------------------------------------
[52804.640104] python3/2984 is trying to acquire lock:
[52804.640581] ffff88810e642678 (nlk_cb_mutex-GENERIC){+.+.}-{3:3}, at: netlink_dump+0xb3/0x780
[52804.641417]
but task is already holding lock:
[52804.642010] ffffffff83bde4c8 (dpll_lock){+.+.}-{3:3}, at: dpll_lock_dumpit+0x13/0x20
[52804.642747]
which lock already depends on the new lock.
[52804.643551]
the existing dependency chain (in reverse order) is:
[52804.644259]
-> #1 (dpll_lock){+.+.}-{3:3}:
[52804.644836] lock_acquire+0x174/0x3e0
[52804.645271] __mutex_lock+0x119/0x1150
[52804.645723] dpll_lock_dumpit+0x13/0x20
[52804.646169] genl_start+0x266/0x320
[52804.646578] __netlink_dump_start+0x321/0x450
[52804.647056] genl_family_rcv_msg_dumpit+0x155/0x1e0
[52804.647575] genl_rcv_msg+0x1ed/0x3b0
[52804.648001] netlink_rcv_skb+0xdc/0x210
[52804.648440] genl_rcv+0x24/0x40
[52804.648831] netlink_unicast+0x2f1/0x490
[52804.649290] netlink_sendmsg+0x36d/0x660
[52804.649742] __sock_sendmsg+0x73/0xc0
[52804.650165] __sys_sendto+0x184/0x210
[52804.650597] __x64_sys_sendto+0x72/0x80
[52804.651045] do_syscall_64+0x6f/0x140
[52804.651474] entry_SYSCALL_64_after_hwframe+0x46/0x4e
[52804.652001]
-> #0 (nlk_cb_mutex-GENERIC){+.+.}-{3:3}:
[52804.652650] check_prev_add+0x1ae/0x1280
[52804.653107] __lock_acquire+0x1ed3/0x29a0
[52804.653559] lock_acquire+0x174/0x3e0
[52804.653984] __mutex_lock+0x119/0x1150
[52804.654423] netlink_dump+0xb3/0x780
[52804.654845] __netlink_dump_start+0x389/0x450
[52804.655321] genl_family_rcv_msg_dumpit+0x155/0x1e0
[52804.655842] genl_rcv_msg+0x1ed/0x3b0
[52804.656272] netlink_rcv_skb+0xdc/0x210
[52804.656721] genl_rcv+0x24/0x40
[52804.657119] netlink_unicast+0x2f1/0x490
[52804.657570] netlink_sendmsg+0x36d/0x660
[52804.658022] __sock_sendmsg+0x73/0xc0
[52804.658450] __sys_sendto+0x184/0x210
[52804.658877] __x64_sys_sendto+0x72/0x80
[52804.659322] do_syscall_64+0x6f/0x140
[52804.659752] entry_SYSCALL_64_after_hwframe+0x46/0x4e
[52804.660281]
other info that might help us debug this:
[52804.661077] Possible unsafe locking scenario:
[52804.661671] CPU0 CPU1
[52804.662129] ---- ----
[52804.662577] lock(dpll_lock);
[52804.662924] lock(nlk_cb_mutex-GENERIC);
[52804.663538] lock(dpll_lock);
[52804.664073] lock(nlk_cb_mutex-GENERIC);
[52804.664490]
The issue as follows: __netlink_dump_start() calls control->start(cb)
with nlk->cb_mutex held. In control->start(cb) the dpll_lock is taken.
Then nlk->cb_mutex is released and taken again in netlink_dump(), while
dpll_lock still being held. That leads to ABBA deadlock when another
CPU races with the same operation.
Fix this by moving dpll_lock taking into dumpit() callback which ensures
correct lock taking order.
Fixes: 9d71b54b65 ("dpll: netlink: Add DPLL framework base functions")
Signed-off-by: Jiri Pirko <jiri@nvidia.com>
Reviewed-by: Arkadiusz Kubalewski <arkadiusz.kubalewski@intel.com>
Link: https://lore.kernel.org/r/20240207115902.371649-1-jiri@resnulli.us
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Similar to what is done in dpll_device_unregister(), add assertion to
__dpll_pin_unregister() to make sure driver does not try to unregister
non-registered pin.
Signed-off-by: Jiri Pirko <jiri@nvidia.com>
Reviewed-by: Vadim Fedorenko <vadim.fedorenko@linux.dev>
Reviewed-by: Arkadiusz Kubalewski <arkadiusz.kubalewski@intel.com>
Link: https://lore.kernel.org/r/20240206074853.345744-1-jiri@resnulli.us
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Pass additional argunent status_error over lock_status_get()
so drivers can fill it up. In case they do, expose the value over
previously introduced attribute to user. Do it only in case the
current lock_status is either "unlocked" or "holdover".
Signed-off-by: Jiri Pirko <jiri@nvidia.com>
Acked-by: Vadim Fedorenko <vadim.fedorenko@linux.dev>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
This is cosmetics. Move the call of xa_erase() in dpll_pin_put()
so the order of cleanup calls matches the error path of
dpll_pin_alloc().
Signed-off-by: Jiri Pirko <jiri@nvidia.com>
Reviewed-by: Vadim Fedorenko <vadim.fedorenko@linux.dev>
Link: https://lore.kernel.org/r/20240130155814.268622-1-jiri@resnulli.us
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
In case of multiple kernel module instances using the same dpll device:
if only one registers dpll device, then only that one can register
directly connected pins with a dpll device. When unregistered parent is
responsible for determining if the muxed pin can be registered with it
or not, the drivers need to be loaded in serialized order to work
correctly - first the driver instance which registers the direct pins
needs to be loaded, then the other instances could register muxed type
pins.
Allow registration of a pin with a parent even if the parent was not
yet registered, thus allow ability for unserialized driver instance
load order.
Do not WARN_ON notification for unregistered pin, which can be invoked
for described case, instead just return error.
Fixes: 9431063ad3 ("dpll: core: Add DPLL framework base functions")
Fixes: 9d71b54b65 ("dpll: netlink: Add DPLL framework base functions")
Reviewed-by: Jan Glaza <jan.glaza@intel.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Arkadiusz Kubalewski <arkadiusz.kubalewski@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If parent pin was unregistered but child pin was not, the userspace
would see the "zombie" pins - the ones that were registered with
a parent pin (dpll_pin_on_pin_register(..)).
Technically those are not available - as there is no dpll device in the
system. Do not dump those pins and prevent userspace from any
interaction with them. Provide a unified function to determine if the
pin is available and use it before acting/responding for user requests.
Fixes: 9d71b54b65 ("dpll: netlink: Add DPLL framework base functions")
Reviewed-by: Jan Glaza <jan.glaza@intel.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Arkadiusz Kubalewski <arkadiusz.kubalewski@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When a kernel module is unbound but the pin resources were not entirely
freed (other kernel module instance of the same PCI device have had kept
the reference to that pin), and kernel module is again bound, the pin
properties would not be updated (the properties are only assigned when
memory for the pin is allocated), prop pointer still points to the
kernel module memory of the kernel module which was deallocated on the
unbind.
If the pin dump is invoked in this state, the result is a kernel crash.
Prevent the crash by storing persistent pin properties in dpll subsystem,
copy the content from the kernel module when pin is allocated, instead of
using memory of the kernel module.
Fixes: 9431063ad3 ("dpll: core: Add DPLL framework base functions")
Fixes: 9d71b54b65 ("dpll: netlink: Add DPLL framework base functions")
Reviewed-by: Jan Glaza <jan.glaza@intel.com>
Reviewed-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
Signed-off-by: Arkadiusz Kubalewski <arkadiusz.kubalewski@intel.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If pin type is not expected, or pin properities failed to allocate
memory, the unwind error path shall not destroy pin's xarrays, which
were not yet initialized.
Add new goto label and use it to fix broken error path.
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Arkadiusz Kubalewski <arkadiusz.kubalewski@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add a new netlink attribute to expose fractional frequency offset value
for a pin. Add an op to get the value from the driver.
Signed-off-by: Jiri Pirko <jiri@nvidia.com>
Acked-by: Vadim Fedorenko <vadim.fedorenko@linux.dev>
Acked-by: Arkadiusz Kubalewski <arkadiusz.kubalewski@intel.com>
Link: https://lore.kernel.org/r/20240103132838.1501801-2-jiri@resnulli.us
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Pin ID is just a number. Nobody should rely on a certain value, instead,
user should use either pin-id-get op or RTNetlink to get it.
Unify the pin ID allocation behavior with what there is already
implemented for dpll devices.
Signed-off-by: Jiri Pirko <jiri@nvidia.com>
Link: https://lore.kernel.org/r/20231212150605.1141261-1-jiri@resnulli.us
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Mode supported is currently reported to the user exactly the same, as
the current mode. That's because mode changing is not implemented.
Remove the leftover mode_supported() op and use mode_get() to fill up
the supported mode exposed to user.
One, if even, mode changing is going to be introduced, this could be
very easily taken back. In the meantime, prevent drivers form
implementing this in wrong way (as for example recent netdevsim
implementation attempt intended to do).
Signed-off-by: Jiri Pirko <jiri@nvidia.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
User may not pass DPLL_A_PIN_STATE attribute in the pin set operation
message. Sanitize that by checking if the attr pointer is not null
and process the passed state attribute value only in that case.
Reported-by: Xingyuan Mo <hdthky0@gmail.com>
Fixes: 9d71b54b65 ("dpll: netlink: Add DPLL framework base functions")
Signed-off-by: Jiri Pirko <jiri@nvidia.com>
Acked-by: Vadim Fedorenko <vadim.fedorenko@linux.dev>
Link: https://lore.kernel.org/r/20231211083758.1082853-1-jiri@resnulli.us
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
We should clean the skb resource if genlmsg_put_reply failed.
Fixes: 9d71b54b65 ("dpll: netlink: Add DPLL framework base functions")
Signed-off-by: Hao Ge <gehao@kylinos.cn>
Reviewed-by: Vadim Fedorenko <vadim.fedorenko@linux.dev>
Link: https://lore.kernel.org/r/20231121013709.73323-1-gehao@kylinos.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Align the approach of pin frequency set behavior with the approach
introduced with pin phase adjust set.
Fail the request if any of devices did not registered the callback ops.
If callback op on any pin's registered device fails, return error and
rollback the value to previous one.
Signed-off-by: Arkadiusz Kubalewski <arkadiusz.kubalewski@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add callback ops for pin-dpll phase measurement.
Add callback for pin signal phase adjustment.
Add min and max phase adjustment values to pin proprties.
Invoke callbacks in dpll_netlink.c when filling the pin details to
provide user with phase related attribute values.
Signed-off-by: Arkadiusz Kubalewski <arkadiusz.kubalewski@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add attributes for providing the user with:
- measurement of signals phase offset between pin and dpll
- ability to adjust the phase of pin signal
Signed-off-by: Arkadiusz Kubalewski <arkadiusz.kubalewski@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In case netdevice represents a SyncE port, the user needs to understand
the connection between netdevice and associated DPLL pin. There might me
multiple netdevices pointing to the same pin, in case of VF/SF
implementation.
Add a IFLA Netlink attribute to nest the DPLL pin handle, similar to
how it is implemented for devlink port. Add a struct dpll_pin pointer
to netdev and protect access to it by RTNL. Expose netdev_dpll_pin_set()
and netdev_dpll_pin_clear() helpers to the drivers so they can set/clear
the DPLL pin relationship to netdev.
Note that during the lifetime of struct dpll_pin the pin handle does not
change. Therefore it is save to access it lockless. It is drivers
responsibility to call netdev_dpll_pin_clear() before dpll_pin_put().
Signed-off-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Arkadiusz Kubalewski <arkadiusz.kubalewski@intel.com>
Signed-off-by: Vadim Fedorenko <vadim.fedorenko@linux.dev>
Signed-off-by: David S. Miller <davem@davemloft.net>
DPLL framework is used to represent and configure DPLL devices
in systems. Each device that has DPLL and can configure inputs
and outputs can use this framework.
Implement dpll netlink framework functions for enablement of dpll
subsystem netlink family.
Co-developed-by: Milena Olech <milena.olech@intel.com>
Signed-off-by: Milena Olech <milena.olech@intel.com>
Co-developed-by: Michal Michalik <michal.michalik@intel.com>
Signed-off-by: Michal Michalik <michal.michalik@intel.com>
Signed-off-by: Vadim Fedorenko <vadim.fedorenko@linux.dev>
Co-developed-by: Arkadiusz Kubalewski <arkadiusz.kubalewski@intel.com>
Signed-off-by: Arkadiusz Kubalewski <arkadiusz.kubalewski@intel.com>
Signed-off-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
DPLL framework is used to represent and configure DPLL devices
in systems. Each device that has DPLL and can configure inputs
and outputs can use this framework.
Implement core framework functions for further interactions
with device drivers implementing dpll subsystem, as well as for
interactions of DPLL netlink framework part with the subsystem
itself.
Co-developed-by: Milena Olech <milena.olech@intel.com>
Signed-off-by: Milena Olech <milena.olech@intel.com>
Co-developed-by: Michal Michalik <michal.michalik@intel.com>
Signed-off-by: Michal Michalik <michal.michalik@intel.com>
Signed-off-by: Vadim Fedorenko <vadim.fedorenko@linux.dev>
Co-developed-by: Arkadiusz Kubalewski <arkadiusz.kubalewski@intel.com>
Signed-off-by: Arkadiusz Kubalewski <arkadiusz.kubalewski@intel.com>
Signed-off-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add a protocol spec for DPLL.
Add code generated from the spec.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Michal Michalik <michal.michalik@intel.com>
Signed-off-by: Vadim Fedorenko <vadim.fedorenko@linux.dev>
Signed-off-by: Arkadiusz Kubalewski <arkadiusz.kubalewski@intel.com>
Signed-off-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
