Red Hat Bugzilla – Bug 190326
hdparm -d 1 /dev/hdc says HDIO_SET_DMA failed: Operation not permitted using_dma = 0 (off)
Last modified: 2007-11-30 17:11:31 EST
Description of problem:
when using default startup for FC5 (grup.conf):
kernel /vmlinuz-2.6.16-1.2096_FC5 ro root=LABEL=/ rhgb quiet
one cannot change DMA settings for CD/DVD-unit.
hdparm -d 1 /dev/hdc
HDIO_SET_DMA failed: Operation not permitted using_dma = 0 (off)
Version-Release number of selected component (if applicable):
The DMA setting is not changabe.
The DMA should be changable.
Starting up the system using extra parameters:
hdc=noprobe, seems to set the device in DMA mode.
I can help with extra information, but please specify what i should do if you
need more info from me.
kernel i use is: 2.6.16-1.2096_FC5.
is your CD/DVD drive connected with a 80-wire cable ? It looks like can't use DMA
with 40-wire cables.