Why can't you sleep while holding spinlock?

Question

In the linux kernel, why can\'t you sleep while holding a spinlock?

Answer 1

I think this mail has a clarity answer:

A process cannot be preempted nor sleep while holding a spinlock due spinlocks behavior. If a process grabs a spinlock and goes to sleep before releasing it. A second process (or an interrupt handler) that to grab the spinlock will busy wait. On an uniprocessor machine the second process will lock the CPU not allowing the first process to wake up and release the spinlock so the second process can continue, it is basically a deadlock.