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

Konstantin A. Lepikhov
2007-12-29T12:23:46Z

Hi Gabriel!

Sunday 16, at 09:31:17 PM you wrote:

> Oliver Joa wrote:
> > Hi,
> >
> > Gabriel C wrote:
> >
> > [...]
> >
> >>>> Also have a look at Documentation/ide.txt.
> >>> I read this already. Searching for "nodma" in this document gives only
> >>> one line:
> >>>
> >>> "ide=nodma" : disable DMA globally for the IDE subsystem.
> >>>
> >>> If the documentation is correct hda=nodma and ideX=nodma should not
> >>> work. I use kernel 2.6.23.1 at the moment.
> >> grep nodma Documentation/ide.txt
> >> "hdx=nodma" : disallow DMA
> >>
> >> ide=foo_option is for the whole ide sub-system where ideX|hdX=foo_option is just for that HDD.
> >
> >
> > /usr/src/linux-2.6.23.1$ grep nodma Documentation/ide.txt
> > "ide=nodma" : disable DMA globally for the IDE subsystem.
> >
> > /usr/src/linux-2.6.21.5$ grep nodma Documentation/ide.txt
> > "ide=nodma" : disable DMA globally for the IDE subsystem.
> >
> > /usr/src/linux-2.6.12# grep nodma Documentation/ide.txt
> > "ide=nodma" : disable DMA globally for the IDE subsystem.
> >
> > Sorry, but I can not find this option, and it does not work. Which
> > kernel do you use?
>
> This is my devel box , running 2.6.24-rc5-git
Are you using modular or in-kernel IDE? Modules ignore cmdline options, so
you must pass this parameter directly to ide_core (e.g. ide_core
options="ide=nodma").

--
WBR et al.