[Libguestfs] Help: Is it possible to use libguestfs in Xen guest OS

Hi All, I installed CentOS 7 as Xen Guest OS(DomU OS), I wonder if it is possible to use libguestfs in this CentOS 7 VM? libguestfs-test-tools reports error: *-bash-4.2# libguestfs-test-tool * ************************************************************ * IMPORTANT NOTICE * * When reporting bugs, include the COMPLETE, UNEDITED * output below in your bug report. * ************************************************************ LIBGUESTFS_BACKEND=libvirt PATH=/sbin:/bin:/usr/sbin:/usr/bin:/usr/X11R6/bin:/opt/vpxxcm/conversion SELinux: sh: getenforce: command not found guestfs_get_append: (null) guestfs_get_autosync: 1 guestfs_get_backend: libvirt guestfs_get_backend_settings: [] guestfs_get_cachedir: /var/tmp guestfs_get_direct: 0 guestfs_get_hv: /usr/libexec/qemu-kvm guestfs_get_memsize: 500 guestfs_get_network: 0 guestfs_get_path: /usr/lib64/guestfs guestfs_get_pgroup: 0 guestfs_get_program: libguestfs-test-tool guestfs_get_recovery_proc: 1 guestfs_get_selinux: 0 guestfs_get_smp: 1 guestfs_get_tmpdir: /tmp guestfs_get_trace: 0 guestfs_get_verbose: 1 host_cpu: x86_64 Launching appliance, timeout set to 600 seconds. libguestfs: launch: program=libguestfs-test-tool libguestfs: launch: version=1.28.1rhel=7,release=1.55.el7.centos.2,libvirt libguestfs: launch: backend registered: unix libguestfs: launch: backend registered: uml libguestfs: launch: backend registered: libvirt libguestfs: launch: backend registered: direct libguestfs: launch: backend=libvirt libguestfs: launch: tmpdir=/tmp/libguestfsqw6Xky libguestfs: launch: umask=0022 libguestfs: launch: euid=0 libguestfs: libvirt version = 1002017 (1.2.17) libguestfs: guest random name = guestfs-eln5avlfeu8xgpd8 libguestfs: [00000ms] connect to libvirt libguestfs: opening libvirt handle: URI = qemu:///system, auth = default+wrapper, flags = 0 libguestfs: successfully opened libvirt handle: conn = 0x7f08e0053d80 libguestfs: qemu version (reported by libvirt) = 1005003 (1.5.3) libguestfs: [00001ms] get libvirt capabilities libguestfs: [00002ms] parsing capabilities XML libguestfs: [00003ms] build appliance libguestfs: [00003ms] begin building supermin appliance libguestfs: [00003ms] run supermin libguestfs: command: run: /usr/bin/supermin5 libguestfs: command: run: \ --build libguestfs: command: run: \ --verbose libguestfs: command: run: \ --if-newer libguestfs: command: run: \ --lock /var/tmp/.guestfs-0/lock libguestfs: command: run: \ --copy-kernel libguestfs: command: run: \ -f ext2 libguestfs: command: run: \ --host-cpu x86_64 libguestfs: command: run: \ /usr/lib64/guestfs/supermin.d libguestfs: command: run: \ -o /var/tmp/.guestfs-0/appliance.d supermin: version: 5.1.10 supermin: rpm: detected RPM version 4.11 supermin: package handler: fedora/rpm supermin: acquiring lock on /var/tmp/.guestfs-0/lock supermin: if-newer: output does not need rebuilding libguestfs: [00011ms] finished building supermin appliance libguestfs: command: run: qemu-img libguestfs: command: run: \ create libguestfs: command: run: \ -f qcow2 libguestfs: command: run: \ -o backing_file=/var/tmp/.guestfs-0/appliance.d/root,backing_fmt=raw libguestfs: command: run: \ /tmp/libguestfsqw6Xky/overlay2 Formatting '/tmp/libguestfsqw6Xky/overlay2', fmt=qcow2 size=4294967296 backing_file='/var/tmp/.guestfs-0/appliance.d/root' backing_fmt='raw' encryption=off cluster_size=65536 lazy_refcounts=off libguestfs: set_socket_create_context: context_new failed: kernel: Invalid argument [you can ignore this UNLESS using SELinux + sVirt] libguestfs: [00031ms] create libvirt XML libguestfs: command: run: dmesg | grep -Eoh 'lpj=[[:digit:]]+' libguestfs: read_lpj_from_dmesg: calculated lpj=2200086 libguestfs: libvirt XML:\n<?xml version="1.0"?>\n<domain type="qemu" xmlns:qemu="http://libvirt.org/schemas/domain/qemu/1.0">\n <name>guestfs-eln5avlfeu8xgpd8</name>\n <memory unit="MiB">500</memory>\n <currentMemory unit="MiB">500</currentMemory>\n <vcpu>1</vcpu>\n <clock offset="utc">\n <timer name="rtc" tickpolicy="catchup"/>\n <timer name="pit" tickpolicy="delay"/>\n <timer name="hpet" present="no"/>\n </clock>\n <os>\n <type>hvm</type>\n <kernel>/var/tmp/.guestfs-0/appliance.d/kernel</kernel>\n <initrd>/var/tmp/.guestfs-0/appliance.d/initrd</initrd>\n <cmdline>panic=1 console=ttyS0 udevtimeout=6000 udev.event-timeout=6000 no_timer_check lpj=2200086 acpi=off printk.time=1 cgroup_disable=memory root=/dev/sdb selinux=0 guestfs_verbose=1 TERM=xterm</cmdline>\n <bios useserial="yes"/>\n </os>\n <on_reboot>destroy</on_reboot>\n <devices>\n <controller type="scsi" index="0" model="virtio-scsi"/>\n <disk device="disk" type="file">\n <source file="/tmp/libguestfsqw6Xky/scratch.1"/>\n <target dev="sda" bus="scsi"/>\n <driver name="qemu" type="raw" cache="unsafe"/>\n <address type="drive" controller="0" bus="0" target="0" unit="0"/>\n </disk>\n <disk type="file" device="disk">\n <source file="/tmp/libguestfsqw6Xky/overlay2"/>\n <target dev="sdb" bus="scsi"/>\n <driver name="qemu" type="qcow2" cache="unsafe"/>\n <address type="drive" controller="0" bus="0" target="1" unit="0"/>\n <shareable/>\n </disk>\n <serial type="unix">\n <source mode="connect" path="/tmp/libguestfsqw6Xky/console.sock"/>\n <target port="0"/>\n </serial>\n <channel type="unix">\n <source mode="connect" path="/tmp/libguestfsqw6Xky/guestfsd.sock"/>\n <target type="virtio" name="org.libguestfs.channel.0"/>\n </channel>\n </devices>\n <qemu:commandline>\n <qemu:env name="TMPDIR" value="/var/tmp"/>\n </qemu:commandline>\n</domain>\n libguestfs: command: run: ls libguestfs: command: run: \ -a libguestfs: command: run: \ -l libguestfs: command: run: \ -Z /var/tmp/.guestfs-0 libguestfs: drwxr-xr-x root root ? . libguestfs: drwxrwxrwt root root ? .. libguestfs: drwxr-xr-x root root ? appliance.d libguestfs: -rw-r--r-- root root ? lock libguestfs: command: run: ls libguestfs: command: run: \ -a libguestfs: command: run: \ -l libguestfs: command: run: \ -Z /tmp/libguestfsqw6Xky libguestfs: drwxr-xr-x root root ? . libguestfs: drwxrwxrwt root root ? .. libguestfs: srw-rw---- root qemu ? console.sock libguestfs: srw-rw---- root qemu ? guestfsd.sock libguestfs: -rw-r--r-- root root ? overlay2 libguestfs: -rw-r--r-- root root ? scratch.1 libguestfs: -rwxr-xr-x root root ? umask-check libguestfs: [00041ms] launch libvirt guest libguestfs: error: could not create appliance through libvirt. Try running qemu directly without libvirt using this environment variable: export LIBGUESTFS_BACKEND=direct Original error from libvirt: internal error: process exited while connecting to monitor: Cannot set up guest memory 'pc.ram': Cannot allocate memory [code=1 domain=10] libguestfs-test-tool: failed to launch appliance libguestfs: closing guestfs handle 0x7f08e0053620 (state 0) libguestfs: command: run: rm libguestfs: command: run: \ -rf /tmp/libguestfsqw6Xky *-bash-4.2# export LIBGUESTFS_BACKEND=direct* *-bash-4.2# libguestfs-test-tool * ************************************************************ * IMPORTANT NOTICE * * When reporting bugs, include the COMPLETE, UNEDITED * output below in your bug report. * ************************************************************ LIBGUESTFS_BACKEND=direct PATH=/sbin:/bin:/usr/sbin:/usr/bin:/usr/X11R6/bin:/opt/vpxxcm/conversion SELinux: sh: getenforce: command not found guestfs_get_append: (null) guestfs_get_autosync: 1 guestfs_get_backend: direct guestfs_get_backend_settings: [] guestfs_get_cachedir: /var/tmp guestfs_get_direct: 0 guestfs_get_hv: /usr/libexec/qemu-kvm guestfs_get_memsize: 500 guestfs_get_network: 0 guestfs_get_path: /usr/lib64/guestfs guestfs_get_pgroup: 0 guestfs_get_program: libguestfs-test-tool guestfs_get_recovery_proc: 1 guestfs_get_selinux: 0 guestfs_get_smp: 1 guestfs_get_tmpdir: /tmp guestfs_get_trace: 0 guestfs_get_verbose: 1 host_cpu: x86_64 Launching appliance, timeout set to 600 seconds. libguestfs: launch: program=libguestfs-test-tool libguestfs: launch: version=1.28.1rhel=7,release=1.55.el7.centos.2,libvirt libguestfs: launch: backend registered: unix libguestfs: launch: backend registered: uml libguestfs: launch: backend registered: libvirt libguestfs: launch: backend registered: direct libguestfs: launch: backend=direct libguestfs: launch: tmpdir=/tmp/libguestfsvt8tnf libguestfs: launch: umask=0022 libguestfs: launch: euid=0 libguestfs: is_openable: /dev/kvm: No such file or directory libguestfs: [00000ms] begin building supermin appliance libguestfs: [00000ms] run supermin libguestfs: command: run: /usr/bin/supermin5 libguestfs: command: run: \ --build libguestfs: command: run: \ --verbose libguestfs: command: run: \ --if-newer libguestfs: command: run: \ --lock /var/tmp/.guestfs-0/lock libguestfs: command: run: \ --copy-kernel libguestfs: command: run: \ -f ext2 libguestfs: command: run: \ --host-cpu x86_64 libguestfs: command: run: \ /usr/lib64/guestfs/supermin.d libguestfs: command: run: \ -o /var/tmp/.guestfs-0/appliance.d supermin: version: 5.1.10 supermin: rpm: detected RPM version 4.11 supermin: package handler: fedora/rpm supermin: acquiring lock on /var/tmp/.guestfs-0/lock supermin: if-newer: output does not need rebuilding libguestfs: [00013ms] finished building supermin appliance libguestfs: [00013ms] begin testing qemu features libguestfs: command: run: /usr/libexec/qemu-kvm libguestfs: command: run: \ -display none libguestfs: command: run: \ -help libguestfs: command: run: /usr/libexec/qemu-kvm libguestfs: command: run: \ -display none libguestfs: command: run: \ -version libguestfs: qemu version 1.5 libguestfs: command: run: /usr/libexec/qemu-kvm libguestfs: command: run: \ -display none libguestfs: command: run: \ -machine accel=kvm:tcg libguestfs: command: run: \ -device ? libguestfs: [00099ms] finished testing qemu features libguestfs: command: run: dmesg | grep -Eoh 'lpj=[[:digit:]]+' libguestfs: read_lpj_from_dmesg: calculated lpj=2200086 [00107ms] /usr/libexec/qemu-kvm \ -global virtio-blk-pci.scsi=off \ -nodefconfig \ -enable-fips \ -nodefaults \ -display none \ -machine accel=kvm:tcg \ -m 500 \ -no-reboot \ -rtc driftfix=slew \ -no-hpet \ -global kvm-pit.lost_tick_policy=discard \ -kernel /var/tmp/.guestfs-0/appliance.d/kernel \ -initrd /var/tmp/.guestfs-0/appliance.d/initrd \ -device virtio-scsi-pci,id=scsi \ -drive file=/tmp/libguestfsvt8tnf/scratch.1,cache=unsafe,format=raw,id=hd0,if=none \ -device scsi-hd,drive=hd0 \ -drive file=/var/tmp/.guestfs-0/appliance.d/root,snapshot=on,id=appliance,cache=unsafe,if=none \ -device scsi-hd,drive=appliance \ -device virtio-serial-pci \ -serial stdio \ -device sga \ -chardev socket,path=/tmp/libguestfsvt8tnf/guestfsd.sock,id=channel0 \ -device virtserialport,chardev=channel0,name=org.libguestfs.channel.0 \ -append 'panic=1 console=ttyS0 udevtimeout=6000 udev.event-timeout=6000 no_timer_check lpj=2200086 acpi=off printk.time=1 cgroup_disable=memory root=/dev/sdb selinux=0 guestfs_verbose=1 TERM=xterm' Could not access KVM kernel module: No such file or directory failed to initialize KVM: No such file or directory Back to tcg accelerator. Cannot set up guest memory 'pc.ram': Cannot allocate memory libguestfs: error: appliance closed the connection unexpectedly, see earlier error messages libguestfs: child_cleanup: 0x7fd127b2d620: child process died libguestfs: sending SIGTERM to process 17471 libguestfs: error: /usr/libexec/qemu-kvm exited with error status 1, see debug messages above libguestfs: error: guestfs_launch failed, see earlier error messages libguestfs-test-tool: failed to launch appliance libguestfs: closing guestfs handle 0x7fd127b2d620 (state 0) libguestfs: command: run: rm libguestfs: command: run: \ -rf /tmp/libguestfsvt8tnf -bash-4.2# After running "*export LIBGUESTFS_BACKEND=direct*", it seems libguestfs will launch another VM inside my VM. Is this necessary? Any response is highly appreciated. Thanks, Allen