Re: [Libguestfs] [PATCH] v2v:windows: prevent Parallels drivers from loading at boot

On Mon, Jun 06, 2016 at 03:12:36PM +0300, Roman Kagan wrote: > Parallels proprietary hypervisor uses RDPMC as the hypercall > instruction. As this instruction is supported since early P6 family, > the drivers didn't even bother to check for the presence of the > corresponding feature in CPUID. > > In QEMU/KVM, however, this instruction triggers #GP unless the VM is run > with PMU (performance monitoring unit) enabled, which is often not the > case (due to its impact on perfromance and migratability). > > So, to prevent crashes upon conversion, stop respective drivers from > loading by disabling the corresponding services. Note that the services > are being disabled ("Start" value set to 4) rather than their node > removed, to avoid confusing the uninstaller which is scheduled to run > from a firstboot script. > > In addition, prl_strg (storage filter driver) is unlinked from the > storage subsystem following the DelReg directive from its .inf file, > otherwise Windows crashes with BSOD 0x7b due to missing dependency of > the storage subsystem. > > Signed-off-by: Roman Kagan <rkagan(a)virtuozzo.com&gt; ACK. Rich.