Hi, $subject says it. Bisecting points to: commit 23673ca740e0eda66901ca801a5a901df378b063 Author: Anthony Liguori <aliguori@xxxxxxxxxx> Date: Tue Mar 5 23:21:23 2013 +0530 qemu-char: add watch support This allows a front-end to request for a callback when the backend is writable again. Signed-off-by: Anthony Liguori <aliguori@xxxxxxxxxx> Signed-off-by: Amit Shah <amit.shah@xxxxxxxxxx> Symtoms: "virsh start" hangs (not always, but most of the time). When killing qemu it prints an error message: error: Failed to start domain fedora-org-virtio error: internal error cannot parse json {"return": [{"name": "chardev-remove"}, {"name": "chardev-add"}, {"name": "query-target"}, {"name": "query-cpu-definitions"}, {"name": "query-machines"}, {"name": "device-list-properties"}, {"name": "qom-list-types"}, {"name": "change-vnc-password"}, {"name": "nbd-server-stop"}, {"name": "nbd-server-add"}, {"name": "nbd-server-start"}, {"name": "qom-get"}, {"name": "qom-set"}, {"name": "qom-list"}, {"name": "query-block-jobs"}, {"name": "query-balloon"}, {"name": "query-migrate-capabilities"}, {"name": "migrate-set-capabilities"}, {"name": "query-migrate"}, {"name": "query-uuid"}, {"name": "query-name"}, {"name": "query-spice"}, {"name": "query-vnc"}, {"name": "query-mice"}, {"name": "query-status"}, {"name": "query-kvm"}, {"name": "query-pci"}, {"name": "query-cpus"}, {"name": "query-blockstats"}, {"name": "query-block"}, {"name": "query-chardev"}, {"name": "query-events"}, {"name": "query-commands"}, {"name": "query-version"}, {"name": "human-monitor-command"}, {"name": "qmp_capabilities So it looks like a bulky qmp reply is written incomplete (or corrupted) and libvirt waits forever for the missing bits ... cheers, Gerd -- libvir-list mailing list libvir-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvir-list