On 10/11/2016 03:44 PM, Aleksei wrote:
> I'm using libvirt, but folks on libvirt mailing list said it makes
> more sense to post here.
> I have a Windows 7 SP1 Pro 64-bit VM which works fine on libvirt 2.3.0
> and Qemu 2.7.0.
> If I enable HyperV features
> (https://libvirt.org/formatdomain.html#elementsFeatures) like
> "relaxed", "spinlocks" etc - VM doesn't boot. "Starting Windows" text
> appears for ~2 seconds (no flying dots, no logo) and then it just goes
> to black screen. If I switch HyperV features back off, it boots
> normally again.
> There are no logs for that attempted boot in the guest - apparently it
> doesn't get to the point when Windows starts logging. No errors logged
> in libvirt's win7.log either.
> Attaching VM xml definition and libvirt-generated Qemu command line -
> only "relaxed" feature is enabled. VM fails with any feature in
> <hyperv> block enabled. Platform-specific values (smbios info etc) are
Win7 + EFI + HyperV will not work.
In short words Windows has bug the HAL.
(Win2k8 and Win7 have the same kernels).
You can find details here: