HDIO_SET_DMA failed: Operation not permitted

[Rick Stevens]

On Fri, 2006-01-27 at 17:49 -0800, Biswajit Nayak wrote:
> No I do not think i did with nodma . Here is the
> output of 
> 
> [root at localhost ocsperf]# cat /proc/cmdline
> ro root=/dev/VolGroup00/LogVol00 rhgb quiet

Ok, so you didn't disable DMA there.  You are, however, using LVM.
Are you using hardware or software RAID?  If so, then you can't just
turn DMA on on one drive, but on all drives that make up the RAID.

We also need to know a bit more about your hardware.  What motherboard
are you using?  What kind of drives?

> 2. How to make sure that the controller/drive does not
> permit dma 
> ?

Again, it could be an interaction between RAID (if used), LVM and your
controller.

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- Rick Stevens, Senior Systems Engineer     rstevens at vitalstream.com -
- VitalStream, Inc.                       http://www.vitalstream.com -
-                                                                    -
-        Polygon: A dead parrot (With apologies to John Cleese)      -
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