Xen block device sharing question.

[deadcollector]

According to Xen documentation I cannot sharing block device in rw mode if I have already mounted block device in dom0 with rw option.
But I do not know can I mount block device with rw option in dom0 and share it in domUs in ro fashion, or mount with ro option in dom0 and share in one domU with rw?

Thanks.
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