On Mon, Aug 31, 2015 at 10:51:02PM +0300, Cyrill Gorcunov wrote: > On Mon, Aug 31, 2015 at 10:36:25PM +0300, Vladimir Davydov wrote: > > > > Yeah, you're right. But then we diverge from pty ref counting design, > > which isn't good IMO. To fix that, let's increment slave's count twice > > on vtty_install, once for file and once for master reference. Then we > > If we increment it twice we have to carry extra-ref bit (which I've > dropped off) otherwise if noone has opened master peer the tty engine > will complain that the number of fd != count. What's worse is that > if noone ever has opened master we have to decrement it back together > with extra ref to be able to close the peer. I mean > > 1) Create pair inside container via slave > > slave:2 (1 - read fd + extra ref) master:0 > > noone opens master and we're calling tty_release, then in > vtty_close we've tp drop the extra ref together with count--, > but if we do so there is still a race window after tty_unlock.
I see. Then it's OK. > > > will only have to decrement slave's count right after tty_init_dev, > > which is safe, because we're holding tty_lock there. Sounds OK? > _______________________________________________ Devel mailing list Devel@openvz.org https://lists.openvz.org/mailman/listinfo/devel
