Nand flash: hang after erase

[Elizabeth Clarke]

I'm playing with nandtest on an mtd partition, and found it hangs after
it has erased the first block. Putting in some debug I find that it gets
as far as the schedule call in mtdchar.c mtd_ioctl line 324. Here's a
snapshot:

	/*
	  FIXME: Allow INTERRUPTIBLE. Which means
	  not having the wait_queue head on the stack.
	  
	  If the wq_head is on the stack, and we
	  leave because we got interrupted, then the
	  wq_head is no longer there when the
	  callback routine tries to wake us up.
	*/
	ret = mtd->erase(mtd, erase);
	if (!ret) {
		set_current_state(TASK_UNINTERRUPTIBLE);
		add_wait_queue(&waitq, &wait);
		if (erase->state != MTD_ERASE_DONE &&
		    erase->state != MTD_ERASE_FAILED)
			schedule();
		remove_wait_queue(&waitq, &wait);
		set_current_state(TASK_RUNNING);
			ret = (erase->state == MTD_ERASE_FAILED)?-EIO:0;
	}

Since I'm still on the beginning of the learning curve somewhat I have
no idea what this is trying to achieve, or where to go from here. Ideas,
pointers, please?

Ta,
Beth