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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">For qemu, the default vhost drive file is “/dev/vhost-net”, when you configured vhost on.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Give the command “modprobe vhost-net” to add host kernel support for vhost.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">This is cannot controlled by libvirt I think.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Wangkai<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif"">From:</span></b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif""> libvirt-users-bounces@redhat.com [mailto:libvirt-users-bounces@redhat.com]
<b>On Behalf Of </b>Asadullah Hussain<br>
<b>Sent:</b> Thursday, July 24, 2014 12:43 AM<br>
<b>To:</b> libvirt-users@redhat.com<br>
<b>Subject:</b> [libvirt-users] vhost-net requested but could not be initialized<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><span style="font-family:"Georgia","serif";color:#0B5394">I am using a custom qemu to launch a vhost enabled VM. The qemu doesn't use the default "/dev/vhost-net" directory as character device. Due to this I am getting the error:<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-family:"Georgia","serif";color:#0B5394"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-family:"Georgia","serif";color:#0B5394">qemu-system-x86_64: -netdev type=tap,id=net1,script=no,downscript=no,ifname=port3,vhost=on: vhost-net requested but could not be initialized<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-family:"Georgia","serif";color:#0B5394"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="color:#0B5394"></span><span style="font-family:"Georgia","serif";color:#0B5394">Is there a way to tell libvirt to
</span><span style="color:#0B5394"></span><span style="font-family:"Georgia","serif";color:#0B5394">avoid using the default /dev/vhost-net file?</span><span style="font-family:"Georgia","serif";color:#0B5394"><o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-family:"Georgia","serif";color:#0B5394"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-family:"Georgia","serif";color:#0B5394">I have tried using the pass-through arguments but libvirt still processes the command and throws the error.<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-family:"Georgia","serif";color:#0B5394"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-family:"Georgia","serif";color:#0B5394">PS: I can successfully create a vhost VM using qemu command-line, so this is a libvirt issue.<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">-- <o:p></o:p></p>
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<p class="MsoNormal">Cheers, <o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Asadullah Hussain<o:p></o:p></p>
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