Hi, This patch series aims to fix the recent patch-series that was just merged to upstream QEMU master branch which adds support for nested migration.
The already merged patch-series was modified during merge to allow migration of vCPU exposed with SVM even though kernel does not support save/restore of required nested state. This was done because of considering backwards-compatability. However, during discussion made after merge, it was realised that since QEMU commit 75d373ef9729 ("target-i386: Disable SVM by default in KVM mode"), an AMD vCPU that is virtualized by KVM doesn't expose SVM by default, even if you use "-cpu host". Therefore, it is unlikely that vCPU expose SVM CPUID flag when user is not running an SVM workload inside guest. Therefore, this patch series change code back to original intent to block migration in case of vCPU exposed with SVM if kernel does not support required capabilities tos ave/restore nested-state. Regards, -Liran