Re: [Qemu-devel] enabling bus-master IDE driver

[Jason Brittain]

Johannes Schindelin wrote:
> Hi,
>
> On Fri, 5 Nov 2004, Jason Brittain wrote:
>
>
> > /dev/hda:
> >  setting using_dma to 1 (on)
> >  HDIO_SET_DMA failed: Operation not permitted
> >  using_dma    =  0 (off)
>
> Are you sure you did as guest root? This error could happen if you try to
> use hdparm as a plain user. 

I was most certainly logged in as root in the guest Linux
when I did that.

> I would expect a different error if the drive
> is not capable of doing DMA.

Well, I haven't seen other situations where drives were
incapable of DMA, so I don't know, but "Operation not
permitted" seems to fit.

How else should I check whether DMA can be turned on?

--
Jason Brittain