Hi Michal

Build with the latest libvirt source code, I found failed to spawn a qemu process, not sure if something wrong with my environment, can you please help to take a look at it?

After build the latest (3.0.0) libvirt, found failed to start an existed domain.

root@s2600wt:/home/taget/qemu# virsh start kvm02

error: Failed to start domain kvm02

error: internal error: Process exited prior to exec: libvirt: QEMU Driver error : Unable to move /dev/mqueue mount: Invalid argument

then I found you had some code get merged, and required to use /dev/mqueue

so mount it then start the domain again:

mount -t mqueue none /dev/mqueue

root@s2600wt:/home/taget/qemu# virsh start kvm02

error: Failed to start domain kvm02

error: An error occurred, but the cause is unknown

some debug log are:

…

2017-01-05 07:48:44.195+0000: 37227: debug : virFileMakePathHelper:2899 : path=/var/run/libvirt/qemu/kvm02.dev/ mode=0777

2017-01-05 07:48:44.195+0000: 37227: debug : virFileMakeParentPath:2971 : path=/var/run/libvirt/qemu/kvm02.dev//hpet

2017-01-05 07:48:44.195+0000: 37227: debug : virFileMakePathHelper:2899 : path=/var/run/libvirt/qemu/kvm02.dev/ mode=0777

2017-01-05 07:48:44.195+0000: 37227: debug : virFileMakeParentPath:2971 : path=/var/run/libvirt/qemu/kvm02.dev//vfio/vfio

2017-01-05 07:48:44.195+0000: 37227: debug : virFileMakePathHelper:2899 : path=/var/run/libvirt/qemu/kvm02.dev//vfio mode=0777

2017-01-05 07:48:44.195+0000: 37227: debug : virFileMakePathHelper:2899 : path=/var/run/libvirt/qemu/kvm02.dev/ mode=0777

2017-01-05 07:48:44.195+0000: 37227: info : virObjectUnref:259 : OBJECT_UNREF: obj=0x7f7dc812fad0

2017-01-05 07:48:44.195+0000: 37227: debug : qemuDomainSetupAllDisks:7076 : Setting up disks

2017-01-05 07:48:44.195+0000: 37227: debug : qemuDomainSetupAllDisks:7085 : Setup all disks

2017-01-05 07:48:44.195+0000: 37227: debug : qemuDomainSetupAllHostdevs:7124 : Setting up hostdevs

2017-01-05 07:48:44.195+0000: 37227: debug : qemuDomainSetupAllHostdevs:7131 : Setup all hostdevs

2017-01-05 07:48:44.195+0000: 37227: debug : qemuDomainSetupAllChardevs:7155 : Setting up chardevs

2017-01-05 07:48:44.195+0000: 37227: debug : qemuDomainSetupAllChardevs:7163 : Setup all chardevs

2017-01-05 07:48:44.195+0000: 37227: debug : qemuDomainSetupAllInputs:7231 : Setting up disks

2017-01-05 07:48:44.195+0000: 37227: debug : qemuDomainSetupAllInputs:7238 : Setup all disks

2017-01-05 07:48:44.195+0000: 37227: debug : qemuDomainSetupAllRNGs:7270 : Setting up RNGs

2017-01-05 07:48:44.195+0000: 37227: debug : qemuDomainSetupAllRNGs:7278 : Setup all RNGs

2017-01-05 07:48:44.195+0000: 37227: debug : virFileMakePathHelper:2899 : path=/dev/pts mode=0777

2017-01-05 07:48:44.195+0000: 37227: debug : virFileMakePathHelper:2899 : path=/dev mode=0777

2017-01-05 07:48:44.195+0000: 37227: debug : virFileMakePathHelper:2899 : path=/dev/shm mode=0777

2017-01-05 07:48:44.195+0000: 37227: debug : virFileMakePathHelper:2899 : path=/dev mode=0777

2017-01-05 07:48:44.195+0000: 37227: debug : virFileMakePathHelper:2899 : path=/dev/mqueue mode=0777

2017-01-05 07:48:44.195+0000: 37227: debug : virFileMakePathHelper:2899 : path=/dev mode=0777

2017-01-05 07:48:44.195+0000: 37227: info : virObjectUnref:259 : OBJECT_UNREF: obj=0x7f7dc812fad0

2017-01-05 07:48:44.195+0000: 37227: info : virObjectUnref:259 : OBJECT_UNREF: obj=0x7f7dc812fad0

2017-01-05 07:48:44.195+0000: 37227: debug : qemuProcessHook:2693 : Hook complete ret=0

2017-01-05 07:48:44.195+0000: 37227: debug : virExec:699 : Done hook 0

2017-01-05 07:48:44.195+0000: 37227: debug : virExec:736 : Setting child uid:gid to 0:0 with caps 0

2017-01-05 07:48:44.195+0000: 37227: debug : virCommandHandshakeChild:435 : Notifying parent for handshake start on 25

2017-01-05 07:48:44.195+0000: 37227: debug : virCommandHandshakeChild:443 : Waiting on parent for handshake complete on 26

libvirt:  error : libvirtd quit during handshake: Input/output error

2017-01-05 07:48:44.216+0000: shutting down, reason=failed

/\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\

I work on the latest libvirt git tree.

commit 866641d4c5706413393913fdb3bb1cd077683d21

Author: Michal Privoznik <mprivozn@redhat.com>

Date:   Sat Dec 24 17:55:48 2016 +0100

    NEWS: Update after qemu namespace fix

    Signed-off-by: Michal Privoznik <mprivozn@redhat.com>

Best Regards

Eli Qiao(乔立勇）OpenStack Core team OTC Intel.

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