DMA in RH8

[bnordin]

I just installed RedHat 8.0 on my system. When I try to enable DMA for my dvd drive, I get the following.
---------------
# /sbin/hdparm -d1 /dev/hdc

/dev/hdc:
setting using_dma to 1 (on)
HDIO_SET_DMA failed: Operation not permitted
using_dma = 0 (off)
---------------
Is this a kernel issue? How do I enable DMA?


System Info:
Mobo: ECS K7VZA
Processor: Athon XP 1800+
Video: (temporarlily Radeon 7000)
Sound: SBLIve!
Memory: 768mb

[Icarus]

I get that same message for my DVD drive, but all of my hard drives say " using_dma = 0 (on)"...even my old 4GB Maxtor...

Try using "/sbin/hdparm -c -d1 /dev/hdc"
That seemed to have better results for me if I remember correctly...Still not on, but better

Even though it failed, the DVD playback was better with no pauses

[bwkaz]

<predictable>You are root when you execute this, correct? </predictable>

[mdwatts]

# /sbin/hdparm -d1 /dev/hdc

Same as I did a couple of days ago when I neglected to notice they were already using root.

[bwkaz]

Oh, the # shell prompt, OK, never mind then. Hmmm... I don't know of anything else it might be...

[Icarus]

Yup...root see :D
[root@Sietch_Tabr root]# /sbin/hdparm -d1 /dev/hdb

/dev/hdb:
setting using_dma to 1 (on)
HDIO_SET_DMA failed: Operation not permitted
using_dma = 0 (off)
it's odd though, only on the DVD drive and it seems to work fine after that, before I run that it's coppy...

[CrashTestDummy9]

Originally posted by mahdi
Yup...root see :D
[root@Sietch_Tabr root]# /sbin/hdparm -d1 /dev/hdb

/dev/hdb:
setting using_dma to 1 (on)
HDIO_SET_DMA failed: Operation not permitted
using_dma = 0 (off)
it's odd though, only on the DVD drive and it seems to work fine after that, before I run that it's coppy... Have you tried using hdparm on /dev/dvd ? I havent got that far with my RH 8.0 yet as ive had to do too many things for OP(other people) .

[Icarus]

Everything I'm finding on this states that it is a kernel problem...now why would Red Hat ship a buggy kernel??

Makes since...in my gkrellm, I can't get disk hdf to display, but hde does and it's on the same cable...Im going to try recompiling from a vanilla see what happens

[mdwatts]

What is connected as hdd?

A older/slower device connected to the same channel can cause this.

[b_usa]

Maybe it's a hardware issue. I just enabled DMA in Red Hat 8.0 on both /dev/hdc and /dev/hdd with the same commands (both cd-roms)

[digitalgoodtime]

i think u r right about it being a hardware\driver issue, while I have not had time to check into much this is what modprobe -c shows

alias block-major-15 cdu31a
alias block-major-16 gscd
alias block-major-17 optcd
alias block-major-18 sjcd
alias block-major-20 mcdx
alias block-major-22 ide-probe-mod
alias block-major-23 mcd
alias block-major-24 sonycd535
alias block-major-25 sbpcd
alias block-major-26 sbpcd
alias block-major-27 sbpcd
alias block-major-29 aztcd
alias block-major-32 cm206

like i haven't researched it but I don't have a sonycd or sound blaster, there is nothing showing my dvd player and to get it to work with mplayer I had to make a sim link to /dev/dvd.... playback is pitifull

my dvd rom is a mitsumi if i remeber right and my CDR is a Velko TDK

just a though, but maybe we need to get the right modules loaded and take out the trash :)

[Icarus]

I found the Red Hat 8.0/DMA not working problem fix!!
From the Release notes...amazing what you can find in those things :D"DMA is disabled on CD-ROM drives in this release in a different but more reliable way than previously. If you are sure that your CD-ROM drive is capable of IDE DMA, place the following line in the /etc/modules.conf file:

options ide-cd dma=1"So, add that to your /etc/modules.conf file and you should be all set (or at least not getting those odd messages anymore:cool:

[mdwatts]

Good job mahdi...

Proves that you should always read the release notes, bug reports, errata etc. from your distros website before posting here or anywhere.

[Icarus]

Originally posted by mdwatts
Good job mahdi...

Proves that you should always read the release notes, bug reports, errata etc. from your distros website before posting here or anywhere. Golly Mr. Watts, do I get a cookie for being a good reader? :D

Heh, I couldn't resist!

Just made the change, it does require a reboot but now it returns what it should!
[root@Sietch_Tabr root]# /sbin/hdparm -d1 /dev/hdb

/dev/hdb:
setting using_dma to 1 (on)
using_dma = 1 (on)

[Icarus]

I thought it would be a good idea to post a link to the Red Hat Linux 8.0 Release Notes (http://www.redhat.com/docs/manuals/linux/RHL-8.0-Manual/release-notes/x86/) as it's not the easiest thing to find and there are TONS of changes with 8.0

They removed xbill :(

Lots of packages have been renamed also...

[mdwatts]

Originally posted by mahdi
Golly Mr. Watts, do I get a cookie for being a good reader? :D

Heh, I couldn't resist!


We'll just deduct the cookie from the thousands you already owe here at LNO. :D

Last time I give you a compliment. :p

BTW... I was not referring to you. Just a comment to the originator of the thread (or any thread).

Check your distros website first.

[Icarus]

Originally posted by mdwatts
We'll just deduct the cookie from the thousands you already owe here at LNO. :D

Last time I give you a compliment. :pGlad to see you can take a joke :)

I've been finding tonnes off good stuff in the new Red Hat docs, it's all good reading!

[mdwatts]

Anyone using any distro should always try their own distros online documentation before posting.

Guess it's only obvious to a few of us. :D