1. 05 2月, 2019 1 次提交
  2. 31 1月, 2019 5 次提交
  3. 30 1月, 2019 1 次提交
  4. 25 1月, 2019 2 次提交
  5. 15 1月, 2019 2 次提交
  6. 11 1月, 2019 1 次提交
  7. 09 1月, 2019 2 次提交
  8. 21 12月, 2018 1 次提交
  9. 20 12月, 2018 2 次提交
  10. 19 12月, 2018 3 次提交
  11. 12 12月, 2018 6 次提交
  12. 07 12月, 2018 2 次提交
  13. 05 12月, 2018 2 次提交
  14. 04 12月, 2018 3 次提交
  15. 27 11月, 2018 6 次提交
  16. 23 11月, 2018 1 次提交
    • P
      RDMA/core: Sync unregistration with netlink commands · 01b67117
      Parav Pandit 提交于
      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: da5c8507 ("RDMA/nldev: add driver-specific resource tracking")
      Signed-off-by: NParav Pandit <parav@mellanox.com>
      Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
      Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>
      01b67117