On 09/17, Will Drewry wrote: > > On Fri, Sep 17, 2010 at 8:29 PM, Oleg Nesterov <oleg@xxxxxxxxxx> wrote: > > > > This looks overcomplicated to me, or I missed something. > > > > I do not understand why should we do this beforehand, and why we need > > copy_namespaces_unattached(). > > > > Can't you just pass current to umh_pipe_setup() (or another helper) as > > the argument? Then this helper can copy ->fs and ->nsproxy itself. > > I wasn't sure if it was reasonable to pass the current task_struct > over, but I certainly can. Why not? current calls call_usermodehelper_exec(), it can't go away until subprocess_info->init() returns, it sleeps on wait_for_completion(). > In practice, this seems to amount to just adding a refcount to all the > namespaces and creating a new nsproxy which isn't really needed. Most > likely, doing what you've suggested above plus the copy_fs_struct and > the swap out will do the trick. I'll try it out and see. That's make > it much clearer I think. Yes, just get_nsproxy() (like fork() does) should be fine in this case. As for copying ->fs, I am not sure actually. core_pattern is global, say it is "|/coredumper". If you change ->root, then exec can fail because that binary is not visible to the coredumping process? Probably we should move core_pattern into ->pid_ns, I dunno. Oleg. -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
