On Wed, Jul 22, 2020 at 04:47:32PM -0400, Eduardo Habkost wrote: > On Wed, Jul 22, 2020 at 08:05:01PM +0200, Jan Kiszka wrote: > > On 22.07.20 19:35, Eduardo Habkost wrote: > > > Hi Jan, > > > > > > What was the last version where it worked for you? Does using > > > "-cpu host,-vmx" help? > > > > Yeah, -vmx does indeed help. > > > > I didn't have the time to bisect yet. Just check my reflog, picked > > eb6490f544, and that works. > > Thanks! > > I could reproduce it locally[1], I will bisect it. > > The good news is that "-cpu host,+vmx" still works, on commit > eb6490f544. > > [1] Linux 5.6.19-300.fc32.x86_64, Intel Core i7-8665U CPU.
Bisected to: commit b16c0e20c74218f2d69710cedad11da7dd4d2190 Author: Paolo Bonzini <pbonz...@redhat.com> Date: Wed May 20 10:49:22 2020 -0400 KVM: add support for AMD nested live migration Support for nested guest live migration is part of Linux 5.8, add the corresponding code to QEMU. The migration format consists of a few flags, is an opaque 4k blob. The blob is in VMCB format (the control area represents the L1 VMCB control fields, the save area represents the pre-vmentry state; KVM does not use the host save area since the AMD manual allows that) but QEMU does not really care about that. However, the flags need to be copied to hflags/hflags2 and back. In addition, support for retrieving and setting the AMD nested virtualization states allows the L1 guest to be reset while running a nested guest, but a small bug in CPU reset needs to be fixed for that to work. Signed-off-by: Paolo Bonzini <pbonz...@redhat.com> -- Eduardo