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From:   Jim Mattson <jmattson@google.com>
Date:   Sun, 10 Dec 2023 14:52:59 -0800
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Subject: Re: [PATCH v4 10/12] KVM: x86: never write to memory from kvm_vcpu_check_block()
To:     Sean Christopherson <seanjc@google.com>
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On Thu, Dec 7, 2023 at 8:21=E2=80=AFAM Sean Christopherson <seanjc@google.c=
om> wrote:
> Doh.  We got the less obvious cases and missed the obvious one.
>
> Ugh, and we also missed a related mess in kvm_guest_apic_has_interrupt().=
  That
> thing should really be folded into vmx_has_nested_events().
>
> Good gravy.  And vmx_interrupt_blocked() does the wrong thing because tha=
t
> specifically checks if L1 interrupts are blocked.
>
> Compile tested only, and definitely needs to be chunked into multiple pat=
ches,
> but I think something like this mess?

The proposed patch does not fix the problem. In fact, it messes things
up so much that I don't get any test results back.

Google has an internal K-U-T test that demonstrates the problem. I
will post it soon.