FAILURE - zero length DMA transfer attempted

[Martin]

Hi,

yesterday I was using my DVD drive (simply reading a DVD). I got lots
of syslog entries that look like this:

ata4: FAILURE - zero length DMA transfer attempted
acd0: setting up DMA failed

This happens on:

FreeBSD kirby 7.2-RELEASE FreeBSD 7.2-RELEASE #0: Wed May  6 09:40:10
CEST 2009     root at kirby:/usr/obj/usr/src/sys/GENERIC  amd64


Drive is Sony NEC Optiarc (SATA):

acd0: DVDR <Optiarc DVD RW AD-7203S/1.06> at ata4-master SATA150

SATA controller is from Intel:

atapci1: <Intel AHCI controller> port
0xe600-0xe607,0xe700-0xe703,0xe800-0xe807, 0xe900-0xe903,0xea00-0xea1f
mem 0xe9306000-0xe93067ff irq 19 at device 31.2 on p ci0
atapci1: [ITHREAD]
atapci1: AHCI Version 01.20 controller with 6 ports detected


There are no problems during reading the DVD, but I thought I it might
still be interesting.

--
Martin