There is some (obvious) mess with "unsigned int" and "int" in the
deadline-io-scheduler (sysfs-section).  Try to change the attribute
"writes_starved":

	root@ezs-mobil:/sys/block/hda/queue# cat scheduler
	noop anticipatory [deadline]
	root@ezs-mobil:/sys/block/hda/queue# cd iosched/
	root@ezs-mobil:/sys/block/hda/queue/iosched# ls
	fifo_batch  front_merges  read_expire  write_expire  writes_starved
	root@ezs-mobil:/sys/block/hda/queue/iosched# cat writes_starved
	2
	root@ezs-mobil:/sys/block/hda/queue/iosched# echo 4 >writes_starved
	root@ezs-mobil:/sys/block/hda/queue/iosched# cat writes_starved
	-2147483648
	root@ezs-mobil:/sys/block/hda/queue/iosched#

Because all attribute-variables are defined as "int", the patch
below changes them to "int". Now it works as expected...
Signed-off-by: Juergen Quade <quade@hsnr.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>