Avi Kivity wrote: > On 06/30/2009 09:16 AM, Han, Weidong wrote: >> Subash Kalbarga wrote: >> >>> Hi >>> >>> I am using kvm-86 on 2.6.28 and I am able to pass through most of my >>> PCI devices successfully. However, I do not see even the KVM BIOS >>> output if I pass through my VGA adapter. I am doing -vga none, >>> -nographic and -pcidevice host=xx:yy.z >>> >>> >>> Should I expect to see the kvm BIOS output? Is VGA pass-through >>> something that is expected to work? >>> >> >> Currently VGA pass-through is not supported in KVM. It needs much >> work to support it. >> >> > > What does it need? > > Here's what I know of: > > - load the vga bios at 0xc0000 > - implement whatever main bios interfaces the vga vios expects > - pass through the vga I/O ports > > Anything else? I think it also needs: - map video RAM: 0xa0000 - 0xbffff - remove Qemu VGA device emulation - reserve enough guest memory space for PCI BARs (most graphics cards has more than 256M memory, I didn't check how much guest memory kvm reserve for PCI BARs) In addition, some graphics cards are specific, such as pBAR must equal to vBAR. To my feeling, there are some tricks to make it work. Regards, Weidong -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
