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

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.