Currently objects specified on the command-line are only partially cleaned up when 'object_del' is issued in either HMP or QMP: the object itself is fully finalized, but the QemuOpts are not removed. This results in the following behavior:
x86_64-softmmu/qemu-system-x86_64 -monitor stdio \ -object memory-backend-ram,id=ram1,size=256M QEMU 2.7.91 monitor - type 'help' for more information (qemu) object_del ram1 (qemu) object_del ram1 object 'ram1' not found (qemu) object_add memory-backend-ram,id=ram1,size=256M Duplicate ID 'ram1' for object Try "help object_add" for more information which can be an issue for use-cases like memory hotplug. This happens on the HMP side because hmp_object_add() attempts to create a temporary QemuOpts entry with ID 'ram1', which ends up conflicting with the command-line-created entry, since it was never cleaned up during the previous hmp_object_del() call. We address this by adding a check in user_creatable_del(), which is called by both qmp_object_del() and hmp_object_del() to handle the actual object cleanup, to determine whether an option group entry matching the object's ID is present and removing it if it is. Note that qmp_object_add() never attempts to create a temporary QemuOpts entry, so it does not encounter the duplicate ID error, which is why this isn't generally visible in libvirt. Cc: "Dr. David Alan Gilbert" <dgilb...@redhat.com> Cc: Markus Armbruster <arm...@redhat.com> Cc: Eric Blake <ebl...@redhat.com> Cc: Daniel Berrange <berra...@redhat.com> Cc: qemu-sta...@nongnu.org Signed-off-by: Michael Roth <mdr...@linux.vnet.ibm.com> --- qom/object_interfaces.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/qom/object_interfaces.c b/qom/object_interfaces.c index ded4d84..23849f9 100644 --- a/qom/object_interfaces.c +++ b/qom/object_interfaces.c @@ -5,6 +5,7 @@ #include "qapi-visit.h" #include "qapi/qobject-output-visitor.h" #include "qapi/opts-visitor.h" +#include "qemu/config-file.h" void user_creatable_complete(Object *obj, Error **errp) { @@ -197,6 +198,7 @@ void user_creatable_del(const char *id, Error **errp) { Object *container; Object *obj; + QemuOptsList *opt_group; container = object_get_objects_root(); obj = object_resolve_path_component(container, id); @@ -209,6 +211,15 @@ void user_creatable_del(const char *id, Error **errp) error_setg(errp, "object '%s' is in use, can not be deleted", id); return; } + + /* if object was defined on the command-line, remove its corresponding + * option group entry + */ + opt_group = qemu_find_opts_err("object", NULL); + if (opt_group) { + qemu_opts_del(qemu_opts_find(opt_group, id)); + } + object_unparent(obj); } -- 1.9.1