Message ID | 1329930831-26837-1-git-send-email-alexander_barabash@mentor.com |
---|---|
State | New |
Headers | show |
On 02/22/2012 06:13 PM, alexander_barabash@mentor.com wrote: > From: Alexander Barabash <alexander_barabash@mentor.com> > > In the old implementation, if the new value of the property links > to the same object, as the old value, that object is first unref-ed, > and then ref-ed. This leads to unintended deinitialization of that object. > > In the new implementation, this is fixed. > > Signed-off-by: Alexander Barabash <alexander_barabash@mentor.com> > --- > qom/object.c | 18 +++++++++++++----- > 1 files changed, 13 insertions(+), 5 deletions(-) > > diff --git a/qom/object.c b/qom/object.c > index 941c291..d1b3ac7 100644 > --- a/qom/object.c > +++ b/qom/object.c > @@ -892,19 +892,19 @@ static void object_set_link_property(Object *obj, Visitor *v, void *opaque, > const char *name, Error **errp) > { > Object **child = opaque; > + Object *old_target; > bool ambiguous = false; > const char *type; > char *path; > gchar *target_type; > + bool clear_old_target = true; > > type = object_property_get_type(obj, name, NULL); > > visit_type_str(v, &path, name, errp); > > - if (*child) { > - object_unref(*child); > - *child = NULL; > - } > + old_target = *child; > + *child = NULL; You can just remove the unref here... > if (strcmp(path, "") != 0) { > Object *target; > @@ -916,7 +916,11 @@ static void object_set_link_property(Object *obj, Visitor *v, void *opaque, > if (ambiguous) { > error_set(errp, QERR_AMBIGUOUS_PATH, path); > } else if (target) { > - object_ref(target); > + if (target != old_target) { > + object_ref(target); ... leave the unconditional ref to target here... > + } else { > + clear_old_target = false; > + } > *child = target; > } else { > target = object_resolve_path(path, &ambiguous); > @@ -930,6 +934,10 @@ static void object_set_link_property(Object *obj, Visitor *v, void *opaque, > } > > g_free(path); > + > + if (clear_old_target && (old_target != NULL)) { > + object_unref(old_target); ... and leave this unref on old_target, without the need for clear_old_target. > + } > } > > void object_property_add_link(Object *obj, const char *name, Paolo
On 02/22/2012 07:17 PM, Paolo Bonzini wrote: > On 02/22/2012 06:13 PM, alexander_barabash@mentor.com wrote: >> From: Alexander Barabash<alexander_barabash@mentor.com> >> >> In the old implementation, if the new value of the property links >> to the same object, as the old value, that object is first unref-ed, >> and then ref-ed. This leads to unintended deinitialization of that object. >> >> In the new implementation, this is fixed. >> >> Signed-off-by: Alexander Barabash<alexander_barabash@mentor.com> >> --- >> qom/object.c | 18 +++++++++++++----- >> 1 files changed, 13 insertions(+), 5 deletions(-) >> >> diff --git a/qom/object.c b/qom/object.c >> index 941c291..d1b3ac7 100644 >> --- a/qom/object.c >> +++ b/qom/object.c >> @@ -892,19 +892,19 @@ static void object_set_link_property(Object *obj, Visitor *v, void *opaque, >> const char *name, Error **errp) >> { >> Object **child = opaque; >> + Object *old_target; >> bool ambiguous = false; >> const char *type; >> char *path; >> gchar *target_type; >> + bool clear_old_target = true; >> >> type = object_property_get_type(obj, name, NULL); >> >> visit_type_str(v,&path, name, errp); >> >> - if (*child) { >> - object_unref(*child); >> - *child = NULL; >> - } >> + old_target = *child; >> + *child = NULL; > You can just remove the unref here... > >> if (strcmp(path, "") != 0) { >> Object *target; >> @@ -916,7 +916,11 @@ static void object_set_link_property(Object *obj, Visitor *v, void *opaque, >> if (ambiguous) { >> error_set(errp, QERR_AMBIGUOUS_PATH, path); >> } else if (target) { >> - object_ref(target); >> + if (target != old_target) { >> + object_ref(target); > ... leave the unconditional ref to target here... > >> + } else { >> + clear_old_target = false; >> + } >> *child = target; >> } else { >> target = object_resolve_path(path,&ambiguous); >> @@ -930,6 +934,10 @@ static void object_set_link_property(Object *obj, Visitor *v, void *opaque, >> } >> >> g_free(path); >> + >> + if (clear_old_target&& (old_target != NULL)) { >> + object_unref(old_target); > ... and leave this unref on old_target, without the need for > clear_old_target. > >> + } >> } >> >> void object_property_add_link(Object *obj, const char *name, > Paolo Agreed. Alex
diff --git a/qom/object.c b/qom/object.c index 941c291..d1b3ac7 100644 --- a/qom/object.c +++ b/qom/object.c @@ -892,19 +892,19 @@ static void object_set_link_property(Object *obj, Visitor *v, void *opaque, const char *name, Error **errp) { Object **child = opaque; + Object *old_target; bool ambiguous = false; const char *type; char *path; gchar *target_type; + bool clear_old_target = true; type = object_property_get_type(obj, name, NULL); visit_type_str(v, &path, name, errp); - if (*child) { - object_unref(*child); - *child = NULL; - } + old_target = *child; + *child = NULL; if (strcmp(path, "") != 0) { Object *target; @@ -916,7 +916,11 @@ static void object_set_link_property(Object *obj, Visitor *v, void *opaque, if (ambiguous) { error_set(errp, QERR_AMBIGUOUS_PATH, path); } else if (target) { - object_ref(target); + if (target != old_target) { + object_ref(target); + } else { + clear_old_target = false; + } *child = target; } else { target = object_resolve_path(path, &ambiguous); @@ -930,6 +934,10 @@ static void object_set_link_property(Object *obj, Visitor *v, void *opaque, } g_free(path); + + if (clear_old_target && (old_target != NULL)) { + object_unref(old_target); + } } void object_property_add_link(Object *obj, const char *name,