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Date:   Thu, 30 Apr 2020 15:59:39 +0530
From:   Srivatsa Vaddagiri <vatsa@codeaurora.org>
To:     Will Deacon <will@kernel.org>
Cc:     konrad.wilk@oracle.com, mst@redhat.com, jasowang@redhat.com,
        jan.kiszka@siemens.com, stefano.stabellini@xilinx.com,
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        alex.bennee@linaro.org, linux-kernel@vger.kernel.org
Subject: Re: [RFC/PATCH 0/1] virtio_mmio: hypervisor specific interfaces for
 MMIO
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 <20200430100821.GC19932@willie-the-truck>
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* Will Deacon <will@kernel.org> [2020-04-30 11:08:22]:

> > This patch is meant to seek comments. If its considered to be in right
> > direction, will work on making it more complete and send the next version!
> 
> What's stopping you from implementing the trapping support in the
> hypervisor? Unlike the other patches you sent out, where the guest memory
> is not accessible to the host, there doesn't seem to be any advantage to
> not having trapping support, or am I missing something here?

Hi Will,
	I have had this discussion with hypervisor folks. They seem to be
concerned about complexity of having a VM's fault be handled in another
untrusted VM. They are not keen to add MMIO support.

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