Date: Tue, 6 Oct 2020 17:04:24 -0700
From: Sean Christopherson <sean.j.christopherson@intel.com>
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Subject: Re: [Virtio-fs] [PATCH v4] kvm,
	x86: Exit to user space in case page fault error
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To: Vivek Goyal <vgoyal@redhat.com>
Cc: virtio-fs-list <virtio-fs@redhat.com>, pbonzini@redhat.com, Vitaly Kuznetsov <vkuznets@redhat.com>, linux-kernel@vger.kernel.org, kvm@vger.kernel.org

On Tue, Oct 06, 2020 at 01:35:27PM -0400, Vivek Goyal wrote:
> On Tue, Oct 06, 2020 at 10:17:04AM -0700, Sean Christopherson wrote:
> 
> [..]
> > > > Note, TDX doesn't allow injection exceptions, so reflecting a #PF back
> > > > into the guest is not an option.  
> > > 
> > > Not even #MC? So sad :-)
> > 
> > Heh, #MC isn't allowed either, yet...
> 
> If #MC is not allowd, logic related to hwpoison memory will not work
> as that seems to inject #MC.

Yep.  Piggybacking #MC is undesirable for other reasons, e.g. adds a "hardware"
dependency for what is really a paravirt feature.