Re: [libvirt] [RFC PATCH v2 REBASE 00/18] Introduce vGPU mdev framework to libvirt

-----Original Message----- From: Erik Skultety [mailto:eskultet@redhat.com] Sent: Thursday, March 16, 2017 10:41 PM To: Chen, Xiaoguang <xiaoguang.chen(a)intel.com&gt; Cc: libvir-list(a)redhat.com; He, Yongli <yongli.he(a)intel.com&gt; Subject: Re: [libvirt] [RFC PATCH v2 REBASE 00/18] Introduce vGPU mdev framework to libvirt > [2] 2005 > ubuntu@z-nuc-11:~/vgpu-meta/libvirt-stage$ > *************************************************** > start libvirt-d > 2017-03-09 19:04:57.211+0000: 2059: info : libvirt version: 3.1.0 > 2017-03-09 19:04:57.211+0000: 2059: info : hostname: z-nuc-11.maas > 2017-03-09 19:04:57.211+0000: 2059: error : qemuMonitorOpenUnix:367 : > failed to connect to monitor socket: No such process > 2017-03-09 19:04:57.213+0000: 2059: error : > virMediatedDeviceGetIOMMUGroupDev:153 : internal error: IOMMU group > file > /sys/bus/mdev/devices/894f3983-1a36-42b3-b52c- 1024aca216be/iommu_group > is not a symlink When I saw this error message for the first time in the original thread, I got confused, since this just checks whether the symlink exists, if it doesn't, the vfio device probably also doesn't exist (but take this with a grain of salt, I haven't investigated that deep) and libvirt needs it to pass it onto qemu command line. I hit this issue once by accident in the past and at that time I didn't understand what caused it, but after a reboot it was gone. So seeing it here it caught my eye and I investigated it last week. What I found out was that it's caused by the vfio-mdev module not being loaded automatically as a dependency. I solved it by autoloading the module on system boot. So this is not a libvirt issue, but just for a reference, there is a BZ on this [1]. > 2017-03-09 19:04:57.213+0000: 2003: info : libvirt version: 3.1.0 > 2017-03-09 19:04:57.213+0000: 2003: info : hostname: z-nuc-11.maas > 2017-03-09 19:04:57.213+0000: 2003: error : virNetSocketReadWire:1800 : > End of file while reading data: Input/output error I suppose this corresponds to the problem above, do you hit this error if you work around the vfio-mdev module problem described above?

> > the screen call trace while start the VM (same for Ubuntu, Win10 etc) > ====================================================== > > ubuntu@z-nuc-11:~/vgpu-meta/libvirt-stage$ myvirsh start vgpu-ubuntu > 2017-03-09 19:06:50.483+0000: 2232: info : libvirt version: 3.1.0 > 2017-03-09 19:06:50.483+0000: 2232: info : hostname: z-nuc-11.maas > 2017-03-09 19:06:50.483+0000: 2232: warning : qemuDomainObjTaint:4056 : > Domain id=1 name='vgpu-ubuntu' > uuid=972b5e38-0437-11e7-8f97-d36dba74552d > is tainted: high-privileges > 2017-03-09 19:06:50.819+0000: 2204: info : libvirt version: 3.1.0 > 2017-03-09 19:06:50.819+0000: 2232: warning : > virDomainAuditHostdev:456 > : Unexpected hostdev type while encoding audit message: 4 This one's interesting, again, are you able to hit the error when you work around the missing vfio-mdev module? I'll have a look at this if you actually can hit the error, even if the XML is correct. I posted v3 of the series and also created a new branch 'mdev-next' on my github [2]. I dropped the attribute 'type' from the source address element, so follow the example in the updated docs.

Thanks for giving it a try. Erik [1] https://bugzilla.redhat.com/show_bug.cgi?id=1420572 [2] https://github.com/eskultety/libvirt/commits/mdev-next