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Date: Fri, 26 Apr 2024 10:15:46 -0700
From: Isaku Yamahata <isaku.yamahata@intel.com>
To: Paolo Bonzini <pbonzini@redhat.com>
Cc: Isaku Yamahata <isaku.yamahata@intel.com>,
	Sean Christopherson <seanjc@google.com>,
	linux-kernel@vger.kernel.org, kvm@vger.kernel.org,
	michael.roth@amd.com, isaku.yamahata@linux.intel.com,
	rick.p.edgecombe@intel.com
Subject: Re: [PATCH 09/11] KVM: guest_memfd: Add interface for populating
 gmem pages with user data
Message-ID: <20240426171546.GR3596705@ls.amr.corp.intel.com>
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On Fri, Apr 26, 2024 at 07:44:40AM +0200,
Paolo Bonzini <pbonzini@redhat.com> wrote:

> On Thu, Apr 25, 2024 at 6:51 PM Isaku Yamahata <isaku.yamahata@intel.com> wrote:
> > > AFAIK, unwinding on failure is completely uninteresting, and arguably undesirable,
> > > because undoing LAUNCH_UPDATE or PAGE.ADD will affect the measurement, i.e. there
> > > is no scenario where deleting pages from guest_memfd would allow a restart/resume
> > > of the build process to truly succeed.
> >
> >
> > Just for record.  With the following twist to kvm_gmem_populate,
> > KVM_TDX_INIT_MEM_REGION can use kvm_gmem_populate().  For those who are curious,
> > I also append the callback implementation at the end.
> 
> Nice, thank you very much. Since TDX does not need
> HAVE_KVM_GMEM_PREPARE, if I get rid of FGP_CREAT_ONLY it will work for
> you, right?

Yes, that's right.
-- 
Isaku Yamahata <isaku.yamahata@intel.com>