On śro, lip 22, 2009 at 06:48:55 -0700, H. Peter Anvin wrote: > > | Bisecting...
2.6.27 is good, 2.6.28 is bad. Some 600-odd revisions still to go (will continue in the evening). > Interesting... I have to say I'm more than a bit surprised that you can > mount a filesystem on top of a character device node at all, but there > isn't really a fundamental reason why you couldn't do it, so... Actually it's mounting a device node over a device node. I was really surprised when I learnt that you can mount --bind other things than directories but thought it could be the closest a container can get to a real console. So mounting /dev/pts/0 over /dev/console seemed quite natural to me. > I am assuming that what causes the problem is that you have found a way > (vfsmount) to hold the pts device node busy which doesn't involve the > tty subsystem. This isn't inherently a problem, but it does have > implications for freeing: in particular, the pts node cannot be removed > until the vfsmount is gone, *and* the device number cannot be reclaimed. > It sounds like it's the latter piece which causes problems. Upthread I posted a patch[1] that makes tty_driver_lookup_tty() return NULL (later changed to ERR_PTR(-EIO) and verified it works) in such a case. If the inode can (as you say) legally outlive its matching tty_struct, I guess the patch should go in. If it cannot, well, the patch is bogus. Best regards, Grzegorz Nosek [1] https://lists.linux-foundation.org/pipermail/containers/2009-July/019141.html _______________________________________________ Containers mailing list contain...@lists.linux-foundation.org https://lists.linux-foundation.org/mailman/listinfo/containers _______________________________________________ Devel mailing list Devel@openvz.org https://openvz.org/mailman/listinfo/devel