preemptible spinlock?

I'm learning how spinlock works. I think the main idea spinlock disables preemption is, the other process that's spinning on the lock can acquire lock. but in some implementations of spinlock, like qspinlock in x86 (or mcs lock), I think there's no need to disable preemption. because processes waiting for lock cannot acquire the lock before the lock holder hand over to other process. is enabling preemption in such spinlock a bad idea?