Re: [PATCH] KVM: nVMX: Rework event injection and recovery

[Jan Kiszka <jan.kiszka@siemens.com>]

On 2013-02-20 16:57, Gleb Natapov wrote:
> On Wed, Feb 20, 2013 at 04:51:39PM +0100, Jan Kiszka wrote:
>> On 2013-02-20 16:30, Gleb Natapov wrote:
>>> On Wed, Feb 20, 2013 at 03:53:53PM +0100, Jan Kiszka wrote:
>>>> On 2013-02-20 14:01, Jan Kiszka wrote:
>>>>> This aligns VMX more with SVM regarding event injection and recovery for
>>>>> nested guests. The changes allow to inject interrupts directly from L0
>>>>> to L2.
>>>>>
>>>>> One difference to SVM is that we always transfer the pending event
>>>>> injection into the architectural state of the VCPU and then drop it from
>>>>> there if it turns out that we left L2 to enter L1.
>>>>>
>>>>> VMX and SVM are now identical in how they recover event injections from
>>>>> unperformed vmlaunch/vmresume: We detect that VM_ENTRY_INTR_INFO_FIELD
>>>>> still contains a valid event and, if yes, transfer the content into L1's
>>>>> idt_vectoring_info_field.
>>>>>
>>>>> To avoid that we incorrectly leak an event into the architectural VCPU
>>>>> state that L1 wants to inject, we skip cancellation on nested run.
>>>>>
>>>>> Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
>>>>> ---
>>>>>
>>>>> Survived moderate testing here and (currently) makes sense to me, but
>>>>> please review very carefully. I wouldn't be surprised if I'm still
>>>>> missing some subtle corner case.
>>>>
>>>> Forgot to point this out again: It still takes "KVM: nVMX: Fix injection
>>>> of PENDING_INTERRUPT and NMI_WINDOW exits to L1" to make L0->L2
>>>> injection work. So this patch logically depends on it.
>>>>
>>> But this patch has hunks from that patch.
>>
>> Not mechanically.
>>
> What do you mean?

You can apply them in arbitrary order, just minor offset shifts will be
the result.

> 
>> If you prefer me merging them together, let me know.
>>
> For review not necessary, for applying preferably.

OK, will wait for review on this, then send out a combo patch.

Jan

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