On 2/25/2022 11:04 PM, Xiaoyao Li wrote:
On 2/25/2022 10:54 PM, Jim Mattson wrote:
On Tue, Feb 22, 2022 at 10:19 PM Chenyi Qiang <chenyi.qiang@xxxxxxxxx>
wrote:
Nested handling
- Nested notify VM exits are not supported yet. Keep the same notify
window control in vmcs02 as vmcs01, so that L1 can't escape the
restriction of notify VM exits through launching L2 VM.
- When L2 VM is context invalid, synthesize a nested
EXIT_REASON_TRIPLE_FAULT to L1 so that L1 won't be killed due to L2's
VM_CONTEXT_INVALID happens.
I don't like the idea of making things up without notifying userspace
that this is fictional. How is my customer running nested VMs supposed
to know that L2 didn't actually shutdown, but L0 killed it because the
notify window was exceeded? If this information isn't reported to
userspace, I have no way of getting the information to the customer.
Then, maybe a dedicated software define VM exit for it instead of
reusing triple fault?
Second thought, we can even just return Notify VM exit to L1 to tell L2
causes Notify VM exit, even thought Notify VM exit is not exposed to L1.
