Gao feng <gaofeng@xxxxxxxxxxxxxx> writes: > 于 2012年11月02日 16:54, Eric W. Biederman 写道: >> Gao feng <gaofeng@xxxxxxxxxxxxxx> writes: >> >>> 于 2012年11月02日 15:02, Eric W. Biederman 写道: >>>> Gao feng <gaofeng@xxxxxxxxxxxxxx> writes: >>>> >>>>> we should call pid_ns_release_proc to unmount pid_namespace's >>>>> proc_mnt when copy_net_ns failed in function create_new_namespaces. >>>>> >>>>> otherwise,the proc_mnt will not be freed and because the super_block >>>>> of proc_mnt also add the reference of the pid_namespace,so this >>>>> pid_namespace will never be released too. >>>> >>>> Ouch! >>>> >>>> Have you encountered this failure in practice or is this just from >>>> review? >>> >>> I add some printk in pid_ns_release_proc,it's not called in above case. >>> when copy_net_ns failed,this pid_namespace is not used by any task, >>> so proc_flush_task can't call pid_ns_release_proc to umount this pidns->proc_mnt. >>> it's the only chance we can unmount this pindns->proc_mnt. >>> >>> With this patch,everything runs well. >> >> I have reviewed the code and I don't doubt that this is necessary. >> >> What caused you to look into this failure? Is there some semi-practical >> real world case that someone is hitting? >> > > So far,there is no case hitting this problem. I think what I want to do is to push the changes in my userns development tree instead of solving it the way you have solved it. The way things are currently structured I don't think we can be certain of finding all of the corner cases. Would you be interesting in confirming that problem does not exist in my userns development branch? Eric _______________________________________________ Containers mailing list Containers@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/containers
