Re: Special handling of display/VGA devices in hotplug drivers

From: One Thousand Gnomes
Date: Thu Dec 11 2014 - 18:02:11 EST

> >> The PCI spec said that you were not allowed to hotplug VGA drivers.
> >> The big issue is that POST usually needs to run on those things, and
> >> there is no way to POST a PCI hotplugged device.
> I don't think this is a problem any more, is it? I think X can
> execute option ROMs, and if we assign the guest to a VM, the guest
> BIOS can also do it.

Providing the legacy I/O is routed to that device, it doesn't use DMA and
a few other things. X has been able to POST cards with vm86 or the 8086
emulator stuff for a long time (it had to in order to use most PC cards on
non x86 boxes).

Your bigger problem is the marvellous reliable way that X handles a GPU
simply vanishing, especially a legacy one.

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