Re: How to Switch DMA off for only one Harddisk at Kernelboot

Bartlomiej Zolnierkiewicz
2007-12-17T11:49:34Z

On Monday 17 December 2007, Oliver Joa wrote:
> Hi,
>
> Alan Cox wrote:
>
> [...]
>
> > For the current kernel and libata you can use libata.dma=3, and it will
> > select DMA for disk (1) + CD (2) but not CF cards. With the older IDE it
> > should be sufficient to use hda=nodma
>
> Thanks a lot, but it does not work:
>
> If I use libata.dma=3 I get the following:
> [ 0.000000] Unknown boot option `libata.dma=3': ignoring
>
> And if I use hda=nodma:
> [ 0.000000] ide_setup: hda=nodma -- BAD OPTION
>
> I use kernel 2.6.21.5.
>
> Any Idea?

"hdx=nodma" was added in 2.6.24-rc1, older kernels have only "ide=nodma"

Also "ide=nodma" may not work in older kernel with some buggy host drivers
(they were fixed in 2.6.24-rc1).

Bart