Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Date:   Tue, 13 Jul 2021 20:51:43 +0000
From:   Sean Christopherson <seanjc@google.com>
To:     Paolo Bonzini <pbonzini@redhat.com>
Cc:     isaku.yamahata@intel.com, Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        "H . Peter Anvin" <hpa@zytor.com>,
        Vitaly Kuznetsov <vkuznets@redhat.com>,
        Wanpeng Li <wanpengli@tencent.com>,
        Jim Mattson <jmattson@google.com>,
        Joerg Roedel <joro@8bytes.org>, erdemaktas@google.com,
        Connor Kuehl <ckuehl@redhat.com>, x86@kernel.org,
        linux-kernel@vger.kernel.org, kvm@vger.kernel.org,
        isaku.yamahata@gmail.com,
        Sean Christopherson <sean.j.christopherson@intel.com>
Subject: Re: [RFC PATCH v2 38/69] KVM: x86: Add option to force LAPIC
 expiration wait
Message-ID: <YO3832IMZH/ZLZ4Z@google.com>
References: <cover.1625186503.git.isaku.yamahata@intel.com>
 <357378fcb6e3e2becb6d4f00a5c3d2b00b2c566b.1625186503.git.isaku.yamahata@intel.com>
 <a349d5bf-b85c-34c3-bb88-523df23a2985@redhat.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <a349d5bf-b85c-34c3-bb88-523df23a2985@redhat.com>
Precedence: bulk

On Tue, Jul 06, 2021, Paolo Bonzini wrote:
> On 03/07/21 00:04, isaku.yamahata@intel.com wrote:
> > From: Sean Christopherson <sean.j.christopherson@intel.com>
> > 
> > Add an option to skip the IRR check in kvm_wait_lapic_expire().  This
> > will be used by TDX to wait if there is an outstanding notification for
> > a TD, i.e. a virtual interrupt is being triggered via posted interrupt
> > processing.  KVM TDX doesn't emulate PI processing, i.e. there will
> > never be a bit set in IRR/ISR, so the default behavior for APICv of
> > querying the IRR doesn't work as intended.
> > 
> > Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
> > Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
> 
> Is there a better (existing after the previous patches) flag to test, or
> possibly can it use vm_type following the suggestion I gave for patch 28?

Not sure if there's a "better" flag, but there's most definitely a flag somewhere
that will suffice :-)