From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Zhang Haoyu" <zhanghy@sangfor.com>
Subject: What's the difference between EPT_MISCONFIG and EPT_VIOLATION?
Date: Wed, 3 Dec 2014 17:50:33 +0800
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Cc: "Paolo Bonzini" <pbonzini@redhat.com>,
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	"Michael S.Tsirkin" <mst@redhat.com>
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Hi,

EXIT_REASON_EPT_VIOLATION's corresponding handle is handle_ept_violation(),
and EXIT_REASON_EPT_MISCONFIG's corresponding handle is handle_ept_misconfig(),
what's the difference between them?

I read the SDM-3C 28.2.3 EPT-Induced VM Exits, and found below description,
"An EPT misconfiguration occurs when, in the course of translating 
a guest-physical address, the logical processor encounters an EPT 
paging-structure entry that contains an unsupported value. An EPT 
violation occurs when there is no EPT misconfiguration but the EPT 
paging-structure entries disallow an access using the guest physical
address."

According to above description, EPT-MISCONFIG is from error settings ,
but from the its exit-handle handle_ept_misconfig(),
it seems that handle_ept_misconfig() handles mmio pagefault,
I'm really confused, I think I'm missing something,
any advices?

Thanks,
Zhang Haoyu