On Wed, Oct 02, 2019 at 10:46:03AM +0200, Nicolas Dichtel wrote: > Le 02/10/2019 à 03:20, David Miller a écrit : > > From: Nicolas Dichtel <nicolas.dich...@6wind.com> > > Date: Mon, 30 Sep 2019 18:02:12 +0200 > > > >> The goal of the series is to ease nsid allocation from userland. > >> The first patch is a preparation work and the second enables to receive the > >> new nsid in the answer to RTM_NEWNSID. > > > > The new reply message could break existing apps. > > > > If an app only performs netnsid operations, and fills up the receive > > queue because it isn't reading these new replies (it had no reason to, > > they didn't exist previously), operations will start failing that > > would not fail previously because the receive queue is full. > Yes I see the problem. I was wondering if this was acceptable because the nl > ack > is sent at the end. But nl ack are optional :/ > > > > > Given this, I don't see how we can make the change. > > > Is a new flag attribute ok to turn on this reply? > Why not using the existing NLM_F_ECHO mechanism?
IIUC, if rtnl_net_notifyid() did pass the proper nlmsghdr and portid to rtnl_notify(), the later would automatically notify the caller with updated information if the original request had the NLM_F_ECHO flag.
