kernel.git/drivers/infiniband/core/device.c, branch linux-4.20.y

RDMA/core: Sync unregistration with netlink commands

2019-02-12T19:02:10Z

[ Upstream commit 01b671170d7f82b959dad6d5dbb44d7a915e647d ] When the rdma device is getting removed, get resource info can race with device removal, as below: CPU-0 CPU-1 -------- -------- rdma_nl_rcv_msg() nldev_res_get_cq_dumpit() mutex_lock(device_lock); get device reference mutex_unlock(device_lock); [..] ib_unregister_device() /* Valid reference to * device->dev exists. */ ib_dealloc_device() [..] provider->fill_res_entry(); Even though device object is not freed, fill_res_entry() can get called on device which doesn't have a driver anymore. Kernel core device reference count is not sufficient, as this only keeps the structure valid, and doesn't guarantee the driver is still loaded. Similar race can occur with device renaming and device removal, where device_rename() tries to rename a unregistered device. While this is fine for devices of a class which are not net namespace aware, but it is incorrect for net namespace aware class coming in subsequent series. If a class is net namespace aware, then the below [1] call trace is observed in above situation. Therefore, to avoid the race, keep a reference count and let device unregistration wait until all netlink users drop the reference. [1] Call trace: kernfs: ns required in 'infiniband' for 'mlx5_0' WARNING: CPU: 18 PID: 44270 at fs/kernfs/dir.c:842 kernfs_find_ns+0x104/0x120 libahci i2c_core mlxfw libata dca [last unloaded: devlink] RIP: 0010:kernfs_find_ns+0x104/0x120 Call Trace: kernfs_find_and_get_ns+0x2e/0x50 sysfs_rename_link_ns+0x40/0xb0 device_rename+0xb2/0xf0 ib_device_rename+0xb3/0x100 [ib_core] nldev_set_doit+0x165/0x190 [ib_core] rdma_nl_rcv_msg+0x249/0x250 [ib_core] ? netlink_deliver_tap+0x8f/0x3e0 rdma_nl_rcv+0xd6/0x120 [ib_core] netlink_unicast+0x17c/0x230 netlink_sendmsg+0x2f0/0x3e0 sock_sendmsg+0x30/0x40 __sys_sendto+0xdc/0x160 Fixes: da5c85078215 ("RDMA/nldev: add driver-specific resource tracking") Signed-off-by: Parav Pandit Signed-off-by: Leon Romanovsky Signed-off-by: Jason Gunthorpe Signed-off-by: Sasha Levin

RDMA/core: Refactor ib_register_device() function

2018-10-17T15:43:07Z

ib_register_device() does several allocation and initialization steps. Split it into smaller more readable functions for easy review and maintenance. Signed-off-by: Parav Pandit Reviewed-by: Daniel Jurgens Signed-off-by: Leon Romanovsky Signed-off-by: Doug Ledford

RDMA/core: Fix unwinding flow in case of error to register device

2018-10-17T15:43:07Z

If port pkey list initialization fails, free the port_immutable memory during cleanup path. Currently it is missed out. If cache setup fails, free the pkey list during cleanup path. Fixes: d291f1a65 ("IB/core: Enforce PKey security on QPs") Signed-off-by: Parav Pandit Reviewed-by: Daniel Jurgens Signed-off-by: Leon Romanovsky Signed-off-by: Doug Ledford

RDMA/core: Implement IB device rename function

2018-10-16T17:37:16Z

Generic implementation of IB device rename function. Signed-off-by: Leon Romanovsky Signed-off-by: Doug Ledford

RDMA/core: Use dev_name instead of ibdev->name

2018-09-26T19:51:48Z

These return the same thing but dev_name is a more conventional use of the kernel API. Signed-off-by: Jason Gunthorpe Reviewed-by: Steve Wise Reviewed-by: Leon Romanovsky Reviewed-by: Dennis Dalessandro

RDMA/core: Use dev_err/dbg/etc instead of pr_* + ibdev->name

2018-09-26T19:51:48Z

Any messages related to a device should be printed with the dev_* formatters. This provides greater consistency for the user. The core does not set pr_fmt so this has no significant change. Signed-off-by: Jason Gunthorpe Reviewed-by: Steve Wise Reviewed-by: Leon Romanovsky Reviewed-by: Dennis Dalessandro

RDMA: Fully setup the device name in ib_register_device

2018-09-26T19:51:36Z

The current code has two copies of the device name, ibdev->dev and dev_name(&ibdev->dev), and they are setup at different times, which is very confusing. Set them both up at the same time and make dev_name() the lead name, which is the proper use of the driver core APIs. To make it very clear that the name is not valid until registration pass it in to the ib_register_device() call rather than messing with ibdev->name directly. Also the reorganization now checks that dev_name is unique even if it does not contain a %. Signed-off-by: Jason Gunthorpe Acked-by: Adit Ranadive Reviewed-by: Steve Wise Acked-by: Devesh Sharma Reviewed-by: Shiraz Saleem Reviewed-by: Leon Romanovsky Reviewed-by: Dennis Dalessandro Reviewed-by: Michael J. Ruhl

RDMA/core: Assign device ifindex before publishing the device

2018-09-06T20:34:38Z

Even though device->ifindex is assigned before adding the device in the list which is read by netlink flow, it is better to assign rdma device index before publishing the device in the system to users and clients. Signed-off-by: Parav Pandit Reviewed-by: Daniel Jurgens Signed-off-by: Leon Romanovsky Signed-off-by: Jason Gunthorpe

RDMA/core: Follow correct unregister order between sysfs and cgroup

2018-09-06T20:32:21Z

During register_device() init sequence is, (a) register with rdma cgroup followed by (b) register with sysfs Therefore, unregister_device() sequence should follow the reverse order. Signed-off-by: Parav Pandit Reviewed-by: Daniel Jurgens Signed-off-by: Leon Romanovsky Signed-off-by: Jason Gunthorpe

RDMA/core: Define client_data_lock as rwlock instead of spinlock

2018-09-06T19:45:38Z

Even though device registration/unregistration and client registration/unregistration is not a performance path, define the client_data_lock as rwlock for code clarity. Signed-off-by: Parav Pandit Reviewed-by: Daniel Jurgens Signed-off-by: Leon Romanovsky Signed-off-by: Jason Gunthorpe