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Thanks very much for your response.<div><br /></div><div>I don't quite understand the security ramifications of setting unsafe_nested_virtualization</div><div><br /></div><div>If I understand correctly, one of the core features that BitVisor provides, is a mitigation against DMA attacks, when configured with unsafe_nested_virtualization, would it become possible again to perform a DMA attack?<br /><br />Thanks!<br /><br />14. Sep 2017 17:13 by <a href="mailto:hdk@igel.co.jp" target="_blank" rel="noopener noreferrer">hdk@igel.co.jp</a>:<br /><br /><blockquote class="tutanota_quote" style="border-left: 1px solid #93A3B8; padding-left: 10px; margin-left: 5px;">Hi,<br /><br />From: <<a href="mailto:krad@tuta.io" target="_blank" rel="noopener noreferrer">krad@tuta.io</a>><br />Subject: [BitVisor-users-en:44] Nested Virtualization Support<br />Date: Mon, 11 Sep 2017 09:16:20 +0200 (CEST)<br /><blockquote>I'm wondering if there are any plans for/the status of nested virtualization on bitvisor?<br />I'm assuming if I tried to run for example vmware player or virtualbox on top of bitvisor, these systems do not run/run very slowly because they are unable to use the hardware virtual machine extensions (VT-x/AMD-V).</blockquote><br />In the latest BitVisor <a href="https://bitbucket.org/bitvisor/bitvisor" target="_blank" rel="noopener noreferrer">https://bitbucket.org/bitvisor/bitvisor</a>,<br />"unsafe nested virtualization" is implemented for AMD-V. It can be<br />enabled by setting config.vmm.unsafe_nested_virtualization=1. Unsafe<br />means that an operating system on a hypervisor on BitVisor can access<br />devices directly - no drivers in BitVisor can handle the access - if<br />the hypervisor makes accesses passthrough to devices.<br /><br />Unsafe nested virtualization for VT-x is currently being developed.<br /><br />-- <br />Hideki EIRAKU <<a href="mailto:hdk@igel.co.jp" target="_blank" rel="noopener noreferrer">hdk@igel.co.jp</a>><br />_______________________________________________<br />BitVisor-users-en mailing list<br /><a href="mailto:BitVisor-users-en@bitvisor.org" target="_blank" rel="noopener noreferrer">BitVisor-users-en@bitvisor.org</a><br /><a href="https://www.bitvisor.org/mailman/listinfo/bitvisor-users-en" target="_blank" rel="noopener noreferrer">https://www.bitvisor.org/mailman/listinfo/bitvisor-users-en</a></blockquote></div> </body>
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