mount-2.12r-ggk.tar.gz

[<Andries.Brouwer@cwi.nl>]

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The present situation of util-linux and mount is not quite clear to me.
On kernel.org under utils/util-linux nothing has happened for over a year,
and there is also an empty utils/util-linux-ng.

Anyway, Dirk Gerrits, René Gabriël and Peter Kooijmans sent me
a patch to add support for shared subtrees to the mount from
util-linux 2.12r, and I put up the result for ftp at
ftp://ftp.win.tue.nl/pub/linux-local/utils/mount/mount-2.12r-ggk.tar.gz

They remark that it feels like a kernel bug that --make-unbindable
is not reset by --make-private and suggest the patch

--- pnode.old   2007-04-17 12:53:11.000000000 +0200
+++ pnode.c     2007-04-17 13:22:03.000000000 +0200
@@ -83,6 +83,8 @@
                mnt->mnt_master = NULL;
                if (type == MS_UNBINDABLE)
                        mnt->mnt_flags |= MNT_UNBINDABLE;
+               else
+                       mnt->mnt_flags &= ~MNT_UNBINDABLE;
        }
 }

(with white-space damage - my cut&paste).

Without this patch one needs the detour "--make-shared; --make-private"
in order to reset the "unbindable" flag for a private tree.

Andries



[By the way, this shared subtree stuff is a bit messy,
and impossible to support correctly by mount without help
from the kernel. So far the shared/slave/unbindable status
of mounts is not visible in /proc/mounts or /proc/$$/mountstats.
The above mount makes a feeble attempt to record these flags
in /etc/mtab, but will fail in any nontrivial situation.]