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Date:   Thu, 14 Apr 2022 17:09:06 +0000
From:   Sean Christopherson <seanjc@google.com>
To:     Paolo Bonzini <pbonzini@redhat.com>
Cc:     Isaku Yamahata <isaku.yamahata@gmail.com>,
        isaku.yamahata@intel.com, kvm@vger.kernel.org,
        linux-kernel@vger.kernel.org, Jim Mattson <jmattson@google.com>,
        erdemaktas@google.com, Connor Kuehl <ckuehl@redhat.com>
Subject: Re: [RFC PATCH v5 092/104] KVM: TDX: Handle TDX PV HLT hypercall
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On Mon, Apr 11, 2022, Paolo Bonzini wrote:
> On 4/8/22 16:51, Sean Christopherson wrote:
> > > It also documents how it has to be used.  So this looks more or less okay,
> > > just rename "vmxip" to "interrupt_pending_delivery".
> > 
> > If we're keeping the call back into SEAM, then this belongs in the path of
> > apic_has_interrupt_for_ppr(), not in the HLT-exit path.  To avoid multiple SEAMCALLS
> > in a single exit, VCPU_EXREG_RVI can be added.
> 
> But apic_has_interrupt_for_ppr takes a PPR argument and that is not
> available.
> 
> So I suppose you mean kvm_apic_has_interrupt?

Yeah, I realized that when I actually tried to implement my idea in code :-)

My hopefully-fully-thought-out idea for handling this:

https://lore.kernel.org/all/YlBhuWElVRwYrrS+@google.com
https://lore.kernel.org/all/YlBkiOmTGk8VlWFh@google.com