On śro, sty 07, 2009 at 05:33:49 +0800, Li Zefan wrote:> >> The root cgroup is read-only, so the tasks in it always bind to INADDR_ANY.> >> For other cgroups, write is allowed only if it has no children and the> >> parent is INADDR_ANY.> > > > Yes, I like that. Will update the patch. I assume that I must check> > list_empty(&cgroup->children)?> > Yes.> > > Should I use cgroup_lock()/cgroup_unlock()> > Yes.> > > or other locking? I think it will be safe to do without locks but would> > rather get some expert advice.> > > > No. Without locks, it races with mkdir.> > =============> > //cgroup_lock();> > if (list_empty(&cgrp->children) &&> parent->ipv4_addr == INADDR_ANY)> <--- mkdir()> ipcgroup->ipv4_addr = new_addr;> > //cgroup_unlock();> > ==============> > In the above case, ipcgroup->ipv4_addr = new_addr,> but child_cgroup->ipv4_addr == INADDR_ANY, which is not expected. I see. Thanks a lot! Best regards, Grzegorz Nosek_______________________________________________Containers mailing listContainers@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx://lists.linux-foundation.org/mailman/listinfo/containers
