In the Linux kernel, the following vulnerability has been resolved:

RDMA/hfi1: Prevent use of lock before it is initialized

If there is a failure during probe of hfi1 before the sdma_map_lock is
initialized, the call to hfi1_free_devdata() will attempt to use a lock
that has not been initialized. If the locking correctness validator is on
then an INFO message and stack trace resembling the following may be seen:

  INFO: trying to register non-static key.
  The code is fine but needs lockdep annotation, or maybe
  you didn't initialize this object before use?
  turning off the locking correctness validator.
  Call Trace:
  register_lock_class+0x11b/0x880
  __lock_acquire+0xf3/0x7930
  lock_acquire+0xff/0x2d0
  _raw_spin_lock_irq+0x46/0x60
  sdma_clean+0x42a/0x660 [hfi1]
  hfi1_free_devdata+0x3a7/0x420 [hfi1]
  init_one+0x867/0x11a0 [hfi1]
  pci_device_probe+0x40e/0x8d0

The use of sdma_map_lock in sdma_clean() is for freeing the sdma_map
memory, and sdma_map is not allocated/initialized until after
sdma_map_lock has been initialized. This code only needs to be run if
sdma_map is not NULL, and so checking for that condition will avoid trying
to use the lock before it is initialized.