>> static bool
>> @@ -47,11 +56,26 @@ memfd_backend_memory_alloc(HostMemoryBackend *backend,
>> Error **errp)
>> goto have_fd;
>> }
>>
>> - fd = qemu_memfd_create(TYPE_MEMORY_BACKEND_MEMFD, backend->size,
>> - m->hugetlb, m->hugetlbsize, m->seal ?
>> - F_SEAL_GROW | F_SEAL_SHRINK | F_SEAL_SEAL : 0,
>> - errp);
>> - if (fd == -1) {
>> + if (m->guest_memfd) {
>> + /* User choose to use fully shared guest-memfd to back the VM.. */
>> + if (!backend->share) {
>> + error_setg(errp, "Guest-memfd=on must be used with share=on");
>> + return false;
>> + }
>> +
>> + /* TODO: add huge page support */
>
> Until that's added, the related options should be disabled. m->seal as
> well doesn't seem to be applicable for guest_memfd case.
Which raises the question whether we want a new backend (I think you implement
that in your version).
guest_memfd is rather different in some aspects (e.g., resizing is already
completely forbidden).
What are the pros and cons of either approach?
--
Cheers,
David
