Re: nVMX: Shadowing of CPU_BASED_VM_EXEC_CONTROL broken

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

On 2014-10-08 12:20, Paolo Bonzini wrote:
> Il 08/10/2014 11:51, Jan Kiszka ha scritto:
>>>> Could you point out where the other places L0 sets
>>>> CPU_BASED_VIRTUAL_INTR_PENDING before entering L2?
>> enable_irq_window(). I instrumented it, and it showed up right before
>> vmcs12 state became corrupted.
> 
> But it would write to the vmcs02, not to the shadow VMCS; the shadow
> VMCS is active during copy_shadow_to_vmcs12/copy_vmcs12_to_shadow, and
> at no other time.  It is not clear to me how the VIRTUAL_INTR_PENDING
> bit ended up from the vmcs02 (where it is perfectly fine) to the vmcs12.

Well, but somehow that bit ends up in vmcs12, that's a fact. Also that
the proble disappears when shadowing is disabled. Need to think about
the path again. Maybe there is just a bug, not a conceptual issue.

Jan

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