<div dir="ltr"><div class="gmail_default" style="font-family:georgia,serif;color:rgb(11,83,148)"><div class="gmail_default" style="font-size:13px">Thanks Wangkai but libvirt infact pre-configures network tap devices and pre-opens /dev/vhost-net file and passes these to qemu as open, ready to use file descriptors. </div>
<div class="gmail_default" style="font-size:13px"><br></div><div class="gmail_default" style="font-size:13px">My issue is that my qemu requires that /dev/vhost-net directory is removed and it's kernel module be unloaded. Then it creates a vhost -net device using its own configuration.</div>
</div></div><div class="gmail_extra"><br><br><div class="gmail_quote">On 24 July 2014 07:35, Wangkai (Kevin,C) <span dir="ltr"><<a href="mailto:wangkai86@huawei.com" target="_blank">wangkai86@huawei.com</a>></span> wrote:<br>
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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.<u></u><u></u></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.<u></u><u></u></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.<u></u><u></u></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d"><u></u> <u></u></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">Wangkai<u></u><u></u></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d"><u></u> <u></u></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""> <a href="mailto:libvirt-users-bounces@redhat.com" target="_blank">libvirt-users-bounces@redhat.com</a> [mailto:<a href="mailto:libvirt-users-bounces@redhat.com" target="_blank">libvirt-users-bounces@redhat.com</a>]
<b>On Behalf Of </b>Asadullah Hussain<br>
<b>Sent:</b> Thursday, July 24, 2014 12:43 AM<br>
<b>To:</b> <a href="mailto:libvirt-users@redhat.com" target="_blank">libvirt-users@redhat.com</a><br>
<b>Subject:</b> [libvirt-users] vhost-net requested but could not be initialized<u></u><u></u></span></p>
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<p class="MsoNormal"><u></u> <u></u></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:<u></u><u></u></span></p>
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<p class="MsoNormal"><span style="font-family:"Georgia","serif";color:#0b5394"><u></u> <u></u></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<u></u><u></u></span></p>
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<p class="MsoNormal"><span style="font-family:"Georgia","serif";color:#0b5394"><u></u> <u></u></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"><u></u><u></u></span></p>
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<p class="MsoNormal"><span style="font-family:"Georgia","serif";color:#0b5394"><u></u> <u></u></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.<u></u><u></u></span></p>
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<p class="MsoNormal"><span style="font-family:"Georgia","serif";color:#0b5394"><u></u> <u></u></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.<u></u><u></u></span></p>
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<p class="MsoNormal"><u></u> <u></u></p>
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<p class="MsoNormal">-- <u></u><u></u></p>
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<p class="MsoNormal">Cheers, <u></u><u></u></p>
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<p class="MsoNormal"><u></u> <u></u></p>
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<p class="MsoNormal">Asadullah Hussain<u></u><u></u></p>
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</blockquote></div><br><br clear="all"><div><br></div>-- <br><div dir="ltr"><div>Cheers, </div><div><br></div>Asadullah Hussain</div>
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