kernel/include/linux/mlx4, branch master

net/mlx4_core: Avoid impossible mlx4_db_alloc() order value

2025-02-15T03:47:35Z

GCC can see that the value range for "order" is capped, but this leads it to consider that it might be negative, leading to a false positive warning (with GCC 15 with -Warray-bounds -fdiagnostics-details): ../drivers/net/ethernet/mellanox/mlx4/alloc.c:691:47: error: array subscript -1 is below array bounds of 'long unsigned int *[2]' [-Werror=array-bounds=] 691 | i = find_first_bit(pgdir->bits[o], MLX4_DB_PER_PAGE >> o); | ~~~~~~~~~~~^~~ 'mlx4_alloc_db_from_pgdir': events 1-2 691 | i = find_first_bit(pgdir->bits[o], MLX4_DB_PER_PAGE >> o); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ | | | | | (2) out of array bounds here | (1) when the condition is evaluated to true In file included from ../drivers/net/ethernet/mellanox/mlx4/mlx4.h:53, from ../drivers/net/ethernet/mellanox/mlx4/alloc.c:42: ../include/linux/mlx4/device.h:664:33: note: while referencing 'bits' 664 | unsigned long *bits[2]; | ^~~~ Switch the argument to unsigned int, which removes the compiler needing to consider negative values. Signed-off-by: Kees Cook Link: https://patch.msgid.link/20250210174504.work.075-kees@kernel.org Signed-off-by: Jakub Kicinski

mlx4: Remove unused functions

2025-02-04T22:05:07Z

The last use of mlx4_find_cached_mac() was removed in 2014 by commit 2f5bb473681b ("mlx4: Add ref counting to port MAC table for RoCE") mlx4_zone_free_entries() was added in 2014 by commit 7a89399ffad7 ("net/mlx4: Add mlx4_bitmap zone allocator") but hasn't been used. (The _unique version is used) Remove them. Signed-off-by: Dr. David Alan Gilbert Reviewed-by: Simon Horman Reviewed-by: Tariq Toukan Reviewed-by: Kalesh AP Link: https://patch.msgid.link/20250203185229.204279-1-linux@treblig.org Signed-off-by: Jakub Kicinski

mlx4: Delete custom device management logic

2023-08-23T07:25:28Z

After the conversion to use the auxiliary bus, the custom device management is not needed anymore and can be deleted. Signed-off-by: Petr Pavlu Tested-by: Leon Romanovsky Reviewed-by: Leon Romanovsky Acked-by: Tariq Toukan Signed-off-by: David S. Miller

mlx4: Register mlx4 devices to an auxiliary virtual bus

2023-08-23T07:25:28Z

Add an auxiliary virtual bus to model the mlx4 driver structure. The code is added along the current custom device management logic. Subsequent patches switch mlx4_en and mlx4_ib to the auxiliary bus and the old interface is then removed. Structure mlx4_priv gains a new adev dynamic array to keep track of its auxiliary devices. Access to the array is protected by the global mlx4_intf mutex. Functions mlx4_register_device() and mlx4_unregister_device() are updated to expose auxiliary devices on the bus in order to load mlx4_en and/or mlx4_ib. Functions mlx4_register_auxiliary_driver() and mlx4_unregister_auxiliary_driver() are added to substitute mlx4_register_interface() and mlx4_unregister_interface(), respectively. Function mlx4_do_bond() is adjusted to walk over the adev array and re-adds a specific auxiliary device if its driver sets the MLX4_INTFF_BONDING flag. Signed-off-by: Petr Pavlu Tested-by: Leon Romanovsky Reviewed-by: Leon Romanovsky Acked-by: Tariq Toukan Signed-off-by: David S. Miller

mlx4: Move the bond work to the core driver

2023-08-23T07:25:28Z

Function mlx4_en_queue_bond_work() is used in mlx4_en to start a bond reconfiguration. It gathers data about a new port map setting, takes a reference on the netdev that triggered the change and queues a work object on mlx4_en_priv.mdev.workqueue to perform the operation. The scheduled work is mlx4_en_bond_work() which calls mlx4_bond()/mlx4_unbond() and consequently mlx4_do_bond(). At the same time, function mlx4_change_port_types() in mlx4_core might be invoked to change the port type configuration. As part of its logic, it re-registers the whole device by calling mlx4_unregister_device(), followed by mlx4_register_device(). The two operations can result in concurrent access to the data about currently active interfaces on the device. Functions mlx4_register_device() and mlx4_unregister_device() lock the intf_mutex to gain exclusive access to this data. The current implementation of mlx4_do_bond() doesn't do that which could result in an unexpected behavior. An updated version of mlx4_do_bond() for use with an auxiliary bus goes and locks the intf_mutex when accessing a new auxiliary device array. However, doing so can then result in the following deadlock: * A two-port mlx4 device is configured as an Ethernet bond. * One of the ports is changed from eth to ib, for instance, by writing into a mlx4_port sysfs attribute file. * mlx4_change_port_types() is called to update port types. It invokes mlx4_unregister_device() to unregister the device which locks the intf_mutex and starts removing all associated interfaces. * Function mlx4_en_remove() gets invoked and starts destroying its first netdev. This triggers mlx4_en_netdev_event() which recognizes that the configured bond is broken. It runs mlx4_en_queue_bond_work() which takes a reference on the netdev. Removing the netdev now cannot proceed until the work is completed. * Work function mlx4_en_bond_work() gets scheduled. It calls mlx4_unbond() -> mlx4_do_bond(). The latter function tries to lock the intf_mutex but that is not possible because it is held already by mlx4_unregister_device(). This particular case could be possibly solved by unregistering the mlx4_en_netdev_event() notifier in mlx4_en_remove() earlier, but it seems better to decouple mlx4_en more and break this reference order. Avoid then this scenario by recognizing that the bond reconfiguration operates only on a mlx4_dev. The logic to queue and execute the bond work can be moved into the mlx4_core driver. Only a reference on the respective mlx4_dev object is needed to be taken during the work's lifetime. This removes a call from mlx4_en that can directly result in needing to lock the intf_mutex, it remains a privilege of the core driver. Signed-off-by: Petr Pavlu Tested-by: Leon Romanovsky Reviewed-by: Leon Romanovsky Acked-by: Tariq Toukan Signed-off-by: David S. Miller

mlx4: Get rid of the mlx4_interface.activate callback

2023-08-23T07:25:27Z

The mlx4_interface.activate callback was introduced in commit 79857cd31fe7 ("net/mlx4: Postpone the registration of net_device"). It dealt with a situation when a netdev notifier received a NETDEV_REGISTER event for a new net_device created by mlx4_en but the same device was not yet visible to mlx4_get_protocol_dev(). The callback can be removed now that mlx4_get_protocol_dev() is gone. Signed-off-by: Petr Pavlu Tested-by: Leon Romanovsky Reviewed-by: Leon Romanovsky Acked-by: Tariq Toukan Signed-off-by: David S. Miller

mlx4: Replace the mlx4_interface.event callback with a notifier

2023-08-23T07:25:27Z

Use a notifier to implement mlx4_dispatch_event() in preparation to switch mlx4_en and mlx4_ib to be an auxiliary device. A problem is that if the mlx4_interface.event callback was replaced with something as mlx4_adrv.event then the implementation of mlx4_dispatch_event() would need to acquire a lock on a given device before executing this callback. That is necessary because otherwise there is no guarantee that the associated driver cannot get unbound when the callback is running. However, taking this lock is not possible because mlx4_dispatch_event() can be invoked from the hardirq context. Using an atomic notifier allows the driver to accurately record when it wants to receive these events and solves this problem. A handler registration is done by both mlx4_en and mlx4_ib at the end of their mlx4_interface.add callback. This matches the current situation when mlx4_add_device() would enable events for a given device immediately after this callback, by adding the device on the mlx4_priv.list. Signed-off-by: Petr Pavlu Tested-by: Leon Romanovsky Acked-by: Tariq Toukan Reviewed-by: Leon Romanovsky Signed-off-by: David S. Miller

mlx4: Use 'void *' as the event param of mlx4_dispatch_event()

2023-08-23T07:25:27Z

Function mlx4_dispatch_event() takes an 'unsigned long' as its event parameter. The actual value is none (MLX4_DEV_EVENT_CATASTROPHIC_ERROR), a pointer to mlx4_eqe (MLX4_DEV_EVENT_PORT_MGMT_CHANGE), or a 32-bit integer (remaining events). In preparation to switch mlx4_en and mlx4_ib to be an auxiliary device, the mlx4_interface.event callback is replaced with a notifier and function mlx4_dispatch_event() gets updated to invoke atomic_notifier_call_chain(). This requires forwarding the input 'param' value from the former function to the latter. A problem is that the notifier call takes 'void *' as its 'param' value, compared to 'unsigned long' used by mlx4_dispatch_event(). Re-passing the value would need either punning it to 'void *' or passing down the address of the input 'param'. Both approaches create a number of unnecessary casts. Change instead the input 'param' of mlx4_dispatch_event() from 'unsigned long' to 'void *'. A mlx4_eqe pointer can be passed directly, callers using an int value are adjusted to pass its address. Signed-off-by: Petr Pavlu Reviewed-by: Leon Romanovsky Signed-off-by: David S. Miller

mlx4: Get rid of the mlx4_interface.get_dev callback

2023-08-23T07:25:27Z

Simplify the mlx4 driver interface by removing mlx4_get_protocol_dev() and the associated mlx4_interface.get_dev callbacks. This is done in preparation to use an auxiliary bus to model the mlx4 driver structure. The change is motivated by the following situation: * The mlx4_en interface is being initialized by mlx4_en_add() and mlx4_en_activate(). * The latter activate function calls mlx4_en_init_netdev() -> register_netdev() to register a new net_device. * A netdev event NETDEV_REGISTER is raised for the device. * The netdev notififier mlx4_ib_netdev_event() is called and it invokes mlx4_ib_scan_netdevs() -> mlx4_get_protocol_dev() -> mlx4_en_get_netdev() [via mlx4_interface.get_dev]. This chain creates a problem when mlx4_en gets switched to be an auxiliary driver. It contains two device calls which would both need to take a respective device lock. Avoid this situation by updating mlx4_ib_scan_netdevs() to no longer call mlx4_get_protocol_dev() but instead to utilize the information passed in net_device.parent and net_device.dev_port. This data is sufficient to determine that an updated port is one that the mlx4_ib driver should take care of and to keep mlx4_ib_dev.iboe.netdevs up to date. Following that, update mlx4_ib_get_netdev() to also not call mlx4_get_protocol_dev() and instead scan all current netdevs to find find a matching one. Note that mlx4_ib_get_netdev() is called early from ib_register_device() and cannot use data tracked in mlx4_ib_dev.iboe.netdevs which is not at that point yet set. Finally, remove function mlx4_get_protocol_dev() and the mlx4_interface.get_dev callbacks (only mlx4_en_get_netdev()) as they became unused. Signed-off-by: Petr Pavlu Tested-by: Leon Romanovsky Reviewed-by: Leon Romanovsky Acked-by: Tariq Toukan Signed-off-by: David S. Miller

Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma

2023-02-24T23:11:03Z

Pull rdma updates from Jason Gunthorpe: "Quite a small cycle this time, even with the rc8. I suppose everyone went to sleep over xmas. - Minor driver updates for hfi1, cxgb4, erdma, hns, irdma, mlx5, siw, mana - inline CQE support for hns - Have mlx5 display device error codes - Pinned DMABUF support for irdma - Continued rxe cleanups, particularly converting the MRs to use xarray - Improvements to what can be cached in the mlx5 mkey cache" * tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma: (61 commits) IB/mlx5: Extend debug control for CC parameters IB/hfi1: Fix sdma.h tx->num_descs off-by-one errors IB/hfi1: Fix math bugs in hfi1_can_pin_pages() RDMA/irdma: Add support for dmabuf pin memory regions RDMA/mlx5: Use query_special_contexts for mkeys net/mlx5e: Use query_special_contexts for mkeys net/mlx5: Change define name for 0x100 lkey value net/mlx5: Expose bits for querying special mkeys RDMA/rxe: Fix missing memory barriers in rxe_queue.h RDMA/mana_ib: Fix a bug when the PF indicates more entries for registering memory on first packet RDMA/rxe: Remove rxe_alloc() RDMA/cma: Distinguish between sockaddr_in and sockaddr_in6 by size Subject: RDMA/rxe: Handle zero length rdma iw_cxgb4: Fix potential NULL dereference in c4iw_fill_res_cm_id_entry() RDMA/mlx5: Use rdma_umem_for_each_dma_block() RDMA/umem: Remove unused 'work' member from struct ib_umem RDMA/irdma: Cap MSIX used to online CPUs + 1 RDMA/mlx5: Check reg_create() create for errors RDMA/restrack: Correct spelling RDMA/cxgb4: Fix potential null-ptr-deref in pass_establish() ...