On Thu, 1 Dec 2016, Volodymyr Babchuk wrote:
> > - TEE may run in parallel of the guest OS, this means that we have
> > to make sure the page will never be removed by the guest OS (see
> > XENMEM_decrease_reservation hypercall).
> Hmmm... I don't know how XEN handles guest memory in details. Can we
> somehow pin pages, so they can't be removed until client unregisters
> shared memory buffer?
> In new OP-TEE shmem design there will be call to register shared
> memory. Client will pass list of pages in this call and OP-TEE will
> map them in its address space. At this moment we need to pin them in
> hypervisor, so guest can't get rid of them, until "unregister shared
> memory" call made. Is this possible?
Yes, pages can be pinned, but we need to cover it in the design doc and
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