Cited commit changed devlink to register its netdev notifier block on
the global netdev notifier chain instead of on the per network namespace
one.

However, when changing the network namespace of the devlink instance,
devlink still tries to unregister its notifier block from the chain of
the old namespace and register it on the chain of the new namespace.
This results in corruption of the notifier chains, as the same notifier
block is registered on two different chains: The global one and the per
network namespace one. In turn, this causes other problems such as the
inability to dismantle namespaces due to netdev reference count issues.

Fix by preventing devlink from moving its notifier block between
namespaces.

Reproducer:

 # echo "10 1" > /sys/bus/netdevsim/new_device
 # ip netns add test123
 # devlink dev reload netdevsim/netdevsim10 netns test123
 # ip netns del test123
 [   71.935619] unregister_netdevice: waiting for lo to become free. Usage count = 2
 [   71.938348] leaked reference.

Fixes: 565b4824c39f ("devlink: change port event netdev notifier from per-net to global")
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Link: https://lore.kernel.org/r/20230215073139.1360108-1-idosch@nvidia.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

Currently only the network namespace of devlink instance is monitored
for port events. If netdev is moved to a different namespace and then
unregistered, NETDEV_PRE_UNINIT is missed which leads to trigger
following WARN_ON in devl_port_unregister().
WARN_ON(devlink_port->type != DEVLINK_PORT_TYPE_NOTSET);

Fix this by changing the netdev notifier from per-net to global so no
event is missed.

Fixes: 02a68a47eade ("net: devlink: track netdev with devlink_port assigned")
Signed-off-by: Jiri Pirko <jiri@nvidia.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Link: https://lore.kernel.org/r/20230206094151.2557264-1-jiri@resnulli.us
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

Take the instance lock around devlink_nl_fill() when dumping,
doit takes it already.

We are only dumping basic info so in the worst case we were risking
data races around the reload statistics. Until the big devlink mutex
was removed all relevant code was protected by it, so the missing
instance lock was not exposed.

Fixes: d3efc2a6a6d8 ("net: devlink: remove devlink_mutex")
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Link: https://lore.kernel.org/r/20221216044122.1863550-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Netdevsim triggers a splat on reload, when it destroys regions
with snapshots pending:

  WARNING: CPU: 1 PID: 787 at net/core/devlink.c:6291 devlink_region_snapshot_del+0x12e/0x140
  CPU: 1 PID: 787 Comm: devlink Not tainted 6.1.0-07460-g7ae9888d6e1c #580
  RIP: 0010:devlink_region_snapshot_del+0x12e/0x140
  Call Trace:
   <TASK>
   devl_region_destroy+0x70/0x140
   nsim_dev_reload_down+0x2f/0x60 [netdevsim]
   devlink_reload+0x1f7/0x360
   devlink_nl_cmd_reload+0x6ce/0x860
   genl_family_rcv_msg_doit.isra.0+0x145/0x1c0

This is the locking assert in devlink_region_snapshot_del(),
we're supposed to be holding the region->snapshot_lock here.

Fixes: 2dec18ad826f ("net: devlink: remove region snapshots list dependency on devlink->lock")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

When the resource size changes, the return value of the
'nla_put_u64_64bit' function is not checked. That has been fixed to avoid
rechecking at the next step.

Found by InfoTeCS on behalf of Linux Verification Center
(linuxtesting.org) with SVACE.

Note that this is harmless, we'd error out at the next put().

Signed-off-by: Ilia.Gavrilov <Ilia.Gavrilov@infotecs.ru>
Link: https://lore.kernel.org/r/20221208082821.3927937-1-Ilia.Gavrilov@infotecs.ru
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Expose port function commands to enable / disable migratable
capability, this is used to set the port function as migratable.

Live migration is the process of transferring a live virtual machine
from one physical host to another without disrupting its normal
operation.

In order for a VM to be able to perform LM, all the VM components must
be able to perform migration. e.g.: to be migratable.
In order for VF to be migratable, VF must be bound to VFIO driver with
migration support.

When migratable capability is enabled for a function of the port, the
device is making the necessary preparations for the function to be
migratable, which might include disabling features which cannot be
migrated.

Example of LM with migratable function configuration:
Set migratable of the VF's port function.

$ devlink port show pci/0000:06:00.0/2
pci/0000:06:00.0/2: type eth netdev enp6s0pf0vf1 flavour pcivf pfnum 0
vfnum 1
    function:
        hw_addr 00:00:00:00:00:00 migratable disable

$ devlink port function set pci/0000:06:00.0/2 migratable enable

$ devlink port show pci/0000:06:00.0/2
pci/0000:06:00.0/2: type eth netdev enp6s0pf0vf1 flavour pcivf pfnum 0
vfnum 1
    function:
        hw_addr 00:00:00:00:00:00 migratable enable

Bind VF to VFIO driver with migration support:
$ echo <pci_id> > /sys/bus/pci/devices/0000:08:00.0/driver/unbind
$ echo mlx5_vfio_pci > /sys/bus/pci/devices/0000:08:00.0/driver_override
$ echo <pci_id> > /sys/bus/pci/devices/0000:08:00.0/driver/bind

Attach VF to the VM.
Start the VM.
Perform LM.

Signed-off-by: Shay Drory <shayd@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Acked-by: Shannon Nelson <shannon.nelson@amd.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Expose port function commands to enable / disable RoCE, this is used to
control the port RoCE device capabilities.

When RoCE is disabled for a function of the port, function cannot create
any RoCE specific resources (e.g GID table).
It also saves system memory utilization. For example disabling RoCE enable a
VF/SF saves 1 Mbytes of system memory per function.

Example of a PCI VF port which supports function configuration:
Set RoCE of the VF's port function.

$ devlink port show pci/0000:06:00.0/2
pci/0000:06:00.0/2: type eth netdev enp6s0pf0vf1 flavour pcivf pfnum 0
vfnum 1
    function:
        hw_addr 00:00:00:00:00:00 roce enable

$ devlink port function set pci/0000:06:00.0/2 roce disable

$ devlink port show pci/0000:06:00.0/2
pci/0000:06:00.0/2: type eth netdev enp6s0pf0vf1 flavour pcivf pfnum 0
vfnum 1
    function:
        hw_addr 00:00:00:00:00:00 roce disable

Signed-off-by: Shay Drory <shayd@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

In order to avoid partial request processing, validate the request
before processing it.

Signed-off-by: Shay Drory <shayd@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Some devlink instances may contain thousands of ports. Storing them in
linked list and looking them up is not scalable. Convert the linked list
into xarray.

Signed-off-by: Jiri Pirko <jiri@nvidia.com>
Acked-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Some drivers only reported the driver name in their
devlink_ops::info_get() callback. Now that the core provides this
information, the callback became empty. For such drivers, just
removing the callback would prevent the core from executing
devlink_nl_info_fill() meaning that "devlink dev info" would not
return anything.

Make the callback function optional by executing
devlink_nl_info_fill() even if devlink_ops::info_get() is NULL.

N.B.: the drivers with devlink support which previously did not
implement devlink_ops::info_get() will now also be able to report
the driver name.

Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Reviewed-by: Jacob Keller  <jacob.e.keller@intel.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>