[libvirt] [PATCH v3 2/2] virtlogd: add missing netserver refcount increment on reload

[John Ferlan]

On 10/24/2017 06:47 AM, Nikolay Shirokovskiy wrote:
> After virNetDaemonAddServerPostExec call in virtlogd we should have
> netserver refcount set to 2. One goes to netdaemon servers hashtable
> and one goes to virtlogd own reference to netserver. Let's add
> missing increment in virNetDaemonAddServerPostExec itself while holding
> daemon lock.
> 
> We also have to unref new extra ref after virtlockd call to virNetDaemonAddServerPostExec.
> ---
>  src/locking/lock_daemon.c | 1 +
>  src/rpc/virnetdaemon.c    | 1 +
>  2 files changed, 2 insertions(+)
> 
> diff --git a/src/locking/lock_daemon.c b/src/locking/lock_daemon.c
> index fe3eaf9..41a06b2 100644
> --- a/src/locking/lock_daemon.c
> +++ b/src/locking/lock_daemon.c
> @@ -275,6 +275,7 @@ virLockDaemonNewPostExecRestart(virJSONValuePtr object, bool privileged)
>                                                virLockDaemonClientFree,
>                                                (void*)(intptr_t)(privileged ? 0x1 : 0x0))))
>          goto error;
> +    virObjectUnref(srv);

I need to think a bit more about this one... different model in lockd
vs. logd over @srv usage especially w/r/t this particular path.

I see that in this path eventually something calls virNetDaemonGetServer
instead of storing the @srv in order to add lockProgram... In any case,
I guess I'd be worried/concerned that something could remove @srv
causing the Hash table code to unref/delete the srv... Also, in the
cleanup: path of main() wouldn't the Unref(srv) cause problems?

Again- need to think a bit longer.

John

>  
>      return lockd;
>  
> diff --git a/src/rpc/virnetdaemon.c b/src/rpc/virnetdaemon.c
> index 495bc4b..f3e3ffe 100644
> --- a/src/rpc/virnetdaemon.c
> +++ b/src/rpc/virnetdaemon.c
> @@ -312,6 +312,7 @@ virNetDaemonAddServerPostExec(virNetDaemonPtr dmn,
>  
>      if (virHashAddEntry(dmn->servers, serverName, srv) < 0)
>          goto error;
> +    virObjectRef(srv);
>  
>      virJSONValueFree(object);
>      virObjectUnlock(dmn);
>