On 07/12/20 12:24, stsp wrote:
It tries to enable VME among other things. qemu appears to disable VME by default, unless you do "-cpu host". So we have a situation where the host (which is qemu) doesn't have VME, and guest (dosemu) is trying to enable it. Now obviously KVM_SET_CPUID doesn't check anyting at all and returns success. That later turns into an invalid guest state. Question: should KVM_SET_CPUID check for supported bits, end return error if not everything is supported?
No, it is intentional. Most bits of CPUID are not ever checked by KVM, so userspace is supposed to set values that makes sense or just copy the value of KVM_GET_SUPPORTED_CPUID more or less blindly.
Paolo
