Created attachment 1364116 [details]
build.log

Description of problem:

Not much to go on, but it looks as if libvirt doesn't even try to
run qemu.  Below is an extract from the log, I'll attach the complete
log.

libguestfs: launch libvirt guest
2017-12-07 08:55:57.463+0000: 9754: debug : virDomainCreateXML:166 : conn=0x55d80ef97330, xmlDesc=<?xml version="1.0"?>
<domain type="qemu" xmlns:qemu="http://libvirt.org/schemas/domain/qemu/1.0">
  <name>guestfs-yjm9zt86eyfhfr5u</name>
  <memory unit="MiB">500</memory>
  <currentMemory unit="MiB">500</currentMemory>
  <vcpu>1</vcpu>
  <clock offset="utc">
    <timer name="rtc" tickpolicy="catchup"/>
    <timer name="pit" tickpolicy="delay"/>
    <timer name="hpet" present="no"/>
  </clock>
  <os>
    <type>hvm</type>
    <kernel>/builddir/build/BUILD/libguestfs-1.37.34/tmp/.guestfs-1000/appliance.d/kernel</kernel>
    <initrd>/builddir/build/BUILD/libguestfs-1.37.34/tmp/.guestfs-1000/appliance.d/initrd</initrd>
    <cmdline>panic=1 console=ttyS0 edd=off udevtimeout=6000 udev.event-timeout=6000 no_timer_check printk.time=1 cgroup_disable=memory usbcore.nousb cryptomgr.notests tsc=reliable 8250.nr_uarts=1 root=/dev/sdb selinux=0 guestfs_verbose=1 TERM=vt100</cmdline>
    <bios useserial="yes"/>
  </os>
  <on_reboot>destroy</on_reboot>
  <devices>
    <rng model="virtio">
      <backend model="random">/dev/urandom</backend>
    </rng>
    <controller type="scsi" index="0" model="virtio-scsi"/>
    <disk device="disk" type="file">
      <source file="/builddir/build/BUILD/libguestfs-1.37.34/tmp/libguestfsvvaEfH/scratch1.img"/>
      <target dev="sda" bus="scsi"/>
      <driver name="qemu" type="raw" cache="unsafe"/>
      <address type="drive" controller="0" bus="0" target="0" unit="0"/>
    </disk>
    <disk type="file" device="disk">
      <source file="/builddir/build/BUILD/libguestfs-1.37.34/tmp/libguestfsvvaEfH/overlay2.qcow2"/>
      <target dev="sdb" bus="scsi"/>
      <driver name="qemu" type="qcow2" cache="unsafe"/>
      <address type="drive" controller="0" bus="0" target="1" unit="0"/>
      <shareable/>
    </disk>
    <serial type="unix">
      <source mode="connect" path="/tmp/libguestfslPIuuU/console.sock"/>
      <target port="0"/>
    </serial>
    <channel type="unix">
      <source mode="connect" path="/tmp/libguestfslPIuuU/guestfsd.sock"/>
      <target type="virtio" name="org.libguestfs.channel.0"/>
    </channel>
    <controller type="usb" model="none"/>
    <memballoon model="none"/>
  </devices>
  <qemu:commandline>
    <qemu:env name="TMPDIR" value="/builddir/build/BUILD/libguestfs-1.37.34/tmp"/>
  </qemu:commandline>
</domain>
, flags=0x2
2017-12-07 08:55:57.463+0000: 9754: debug : virNetMessageNew:46 : msg=0x55d80ef9b2a0 tracked=0
2017-12-07 08:55:57.463+0000: 9754: debug : virNetMessageEncodePayload:389 : Encode length as 2332
2017-12-07 08:55:57.463+0000: 9754: info : virNetClientSendInternal:2119 : RPC_CLIENT_MSG_TX_QUEUE: client=0x55d80ef9a1d0 len=2332 prog=536903814 vers=1 proc=10 type=0 status=0 serial=6
2017-12-07 08:55:57.463+0000: 9754: debug : virNetClientCallNew:2072 : New call 0x55d80ef9ad30: msg=0x55d80ef9b2a0, expectReply=1, nonBlock=0
2017-12-07 08:55:57.463+0000: 9754: debug : virNetClientIO:1878 : Outgoing message prog=536903814 version=1 serial=6 proc=10 type=0 length=2332 dispatch=(nil)
2017-12-07 08:55:57.463+0000: 9754: debug : virNetClientIO:1937 : We have the buck head=0x55d80ef9ad30 call=0x55d80ef9ad30
2017-12-07 08:55:57.463+0000: 9754: debug : virNetSocketUpdateIOCallback:2198 : Watch not registered on socket 0x55d80ef99c80
2017-12-07 08:55:57.467+0000: 9754: debug : virNetMessageDecodeLength:161 : Got length, now need 284 total (280 more)
2017-12-07 08:55:57.467+0000: 9754: info : virNetClientCallDispatch:1267 : RPC_CLIENT_MSG_RX: client=0x55d80ef9a1d0 len=284 prog=536903814 vers=1 proc=10 type=1 status=1 serial=6
2017-12-07 08:55:57.467+0000: 9754: debug : virKeepAliveCheckMessage:374 : ka=(nil), client=0x7f0ecfdf6bb0, msg=0x55d80ef9a238
2017-12-07 08:55:57.467+0000: 9754: debug : virNetMessageClear:74 : msg=0x55d80ef9a238 nfds=0
2017-12-07 08:55:57.467+0000: 9754: debug : virNetClientIOEventLoopPassTheBuck:1561 : Giving up the buck 0x55d80ef9ad30
2017-12-07 08:55:57.467+0000: 9754: debug : virNetClientIOEventLoopPassTheBuck:1575 : No thread to pass the buck to
2017-12-07 08:55:57.467+0000: 9754: debug : virNetSocketUpdateIOCallback:2198 : Watch not registered on socket 0x55d80ef99c80
2017-12-07 08:55:57.467+0000: 9754: debug : virNetClientIO:1967 : All done with our call head=(nil) call=0x55d80ef9ad30 rv=0
2017-12-07 08:55:57.467+0000: 9754: debug : virNetMessageFree:87 : msg=0x55d80ef9b2a0 nfds=0 cb=(nil)
libguestfs: error: could not create appliance through libvirt.

Version-Release number of selected component (if applicable):

libvirt 3.10.0-1.fc28

How reproducible:

100%

Steps to Reproduce:
1. Run libguestfs-test-tool