On Thu, Mar 5, 2015 at 11:27 AM, Sergey Senozhatsky <sergey.senozhatsky.w...@gmail.com> wrote: > On (03/05/15 11:04), Minchan Kim wrote: >> > we upgraded our scripts but landed some bugs there? it's up to particular >> > implementation. in your example, I assume, someone used zram with >> > num_devices >= 1000? >> > that's impossible. current num_devices limitation is 32. and uid-s start >> > from 1000. >> >> I meant it. >> If we support use-defined id and someone have used your idea so he can make >> zram >> per-user as uid. After a while, new application stats automatic id assignment >> so upcoming users can consume upcoming user id. yeah, automaic id will start >> from 0 so it's very rare to reach 1000 but who knows? >> My point is in your usecase, the script would be very fragile so it should >> have second plan like automatic id. > > I don't see how it turns any script into a _necessarily fragile_ one > here. there might be buggy scripts, yes. there might be no. > >> > these scripts should check if device has been created anyway, it just adds >> > -EEXIST >> > check. in general "what if user space does something wrong" thing can be >> > beaten by >> > "what if user space does everything right" argument. when script fails we >> > just go >> > and fix that script, I guess. >> >> Yes, I believe finally the script will go automatic id if it was broken. > > No, fixing a script does not imply at all switching to automatic device_id > assignment mode.
If the script fix another way, not automatic id, it might be broken sometime and they should find an another workaround. It will repeat forever, I guess. Anyway, let's wait opinions from userland. Please involve them in this thread rather than another channel. Thanks, Sergey! -- Kind regards, Minchan Kim -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
