Quoting Dave Hansen ([email protected]): > On Wed, 2008-12-17 at 11:55 -0600, Serge E. Hallyn wrote: > > -void free_ipc_ns(struct kref *kref) > > +void put_ipc_ns(struct ipc_namespace *ns) > > { > > - struct ipc_namespace *ns; > > + if (ns && atomic_dec_and_lock(&ns->count, &mq_lock)) { > > + mq_clear_sbinfo(ns); > > + spin_unlock(&mq_lock); > > + mq_put_mnt(ns); > > + free_ipc_ns(ns); > > + } > > +} > > OK, I see now why you wanted to remove the kref and add an atomic_t. > That's probably worth a sentence in the patch description.
Good point, will do. > I know that atomic_dec_and_lock() can be a nice logical thing to do, but > is it necessary here? Basically, is there something that happens under > mq_lock that can re-raise the ns->count? A racing task from another ipc namespace can open a mq file through the VFS and thereby bump the ipc's refcount. Will comment that here and in the patch description. thanks, -serge _______________________________________________ Containers mailing list [email protected] https://lists.linux-foundation.org/mailman/listinfo/containers _______________________________________________ Devel mailing list [email protected] https://openvz.org/mailman/listinfo/devel
