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Re: Where is netbsd-XEN3_DOM0.gz

   big box in a machine room, text console, all usage remote

Obviously no need for AGP.

True, and no need for a vast array of things - basically all video, all sound.

   regular desktop, with what would have been bare metal as the dom0, so
   you can run a domU or two

in the latter case, people want a normalish dom0 kernel.

Can a DOM0 with no AGP run a DOMU with AGP or are there system dependencies?

The basic issue here is "PCI passthrough". Normally, devices on the PCI bus are accessible to the dom0 kernel and are attached by it. A domU kernel does not see any real device, and typically has only xbd/xennet (and vcpu).

With PCI passthough, which was supported in some versions long ago, and might not be supported in any now, some PCI devices can be excluded from dom0 visibility and mapped into a domU, so that a domU can access them (with a driver, just like a native kernel). AGP feels like a particular kind of PCI, so I suspect that with working PCI passthrough, one could attach agp in a domU.

Are there PRs, and can we deal with this by quirks to not attach AGP
when it's going to do something bad?

There's 50446 which has the suggestion to just comment out AGP.  I
wonder if we should just remove the line altogether.  If someone ever
gets around to fixing the issue they can put it back.  In the meantime
why tempt people to un-comment it?

If there is general agreement I will make the change and also update the
PR so that the fixer knows to add the line back.

Manuel seems to think so, so I will not object. My point is that removing AGP from the default kernel is appropriate if a significant amount of hardware has trouble, and not appropriate if it works on most systems and crashes on only a few.

I wonder if anyone has tested with netbsd-8 or -current, and with Xen 4.8. Perhaps this really is buggy in most cases. I didn't see it before, but all my xen dom0s were older hardware with not so fancy graphics.

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