Multiseat with VGAArbiter on 2 Radeon cards

Steffen Schaumburg steffen at
Sat Dec 5 11:30:11 PST 2009

thanks both of you for your replies - I'm going to try the KMS method
first. Now the problem is I can't turn off Arbiter in the kernel, make
menuconfig can find it with the search, but the option isn't in the
menu. Is there a boot option to force off arbiter (or, alternatively, to
force on KMS which would turn off arbiter by necessity?)? I checked the
docs at;a=blob_plain;f=Documentation/vgaarbiter.txt;hb=HEAD 
but can't see anything. Or should I just manually edit the .config file
- I'm inclined to trust menuconfig to not be displaying the option for a
reason, or am I giving it too much credit? Any pointers would be

Thanks, Steffen

Corbin Simpson wrote:
> Multicard and multiseat for radeon doesn't need vgaarb; use KMS
> instead and your cards will both come up at boot.
> Posting from a mobile, pardon my terseness. ~ C.
>> On Dec 5, 2009 9:30 AM, "Tiago Vignatti" <tiago.vignatti at
>> <mailto:tiago.vignatti at>> wrote:
>> On Fri, Dec 04, 2009 at 09:00:19PM +0100, ext Steffen Schaumburg
>> wrote: > Hi everyone, > I'm trying ...
>> yes. And the log says you're indeed using it.
>> > The current status of my work is: > >From pressing the power button
>> to kdm loading it displays i...
>> humm, seems not issue with vga arbitration. I'd guess maybe missed mode
>> setting. Try to start an app on the monitor black and see if
>> connects. If this
>> succeeds then the arbiter is doing its job okay.

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