From mboxrd@z Thu Jan  1 00:00:00 1970
From: Paolo Bonzini <pbonzini@redhat.com>
Subject: Re: [RFC][PATCH] KVM: nVMX: Leave VMX mode on apparent CPU reset
Date: Tue, 17 Dec 2013 14:25:26 +0100
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Cc: Gleb Natapov <gleb@kernel.org>, kvm <kvm@vger.kernel.org>
To: Jan Kiszka <jan.kiszka@siemens.com>
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Il 16/12/2013 10:32, Jan Kiszka ha scritto:
> As long as we do not expose all the VMX related states to user space,
> there is no way to properly reset a VCPU when VMX is enabled. Emulate
> this for now by catching host-side clearings of the feature control MSR.
> This allows to reboot a VM while it is running some hypervisor code.
> 
> Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
> ---
> 
> Better ideas? Or continue to leave it as it is?

The final vmx_vcpu_reset is the only really ugly part, but it is
_really_ ugly...  Can you modify QEMU to restore MSRs first, and reduce
vmx_reset_nested to just

	if (is_guest_mode(vcpu))
		nested_vmx_vmexit(vcpu);

	free_nested(vmx);

?

Paolo