Re: [PATCH] KVM: X86: Fix SMRAM accessing even if VM is shutdown

From: Paolo Bonzini
Date: Thu Feb 08 2018 - 05:31:27 EST


On 08/02/2018 09:57, Xiao Guangrong wrote:
>> Maybe it should return RET_PF_EMULATE, which would cause an emulation
>> failure and then an exit with KVM_EXIT_INTERNAL_ERROR.
>
> So the root cause is that a running vCPU accessing the memory whose memslot
> is being updated (met the condition KVM_MEMSLOT_INVALID is set on the its
> memslot).
>
> The normal #PF handler breaks KVM_RUN and returns -EFAULT to userspace,
> we'd better to make ept-misconfig's handler follow this style as well.

Why return -EFAULT and not attempt emulation (which will fail)?

Paolo