Re: vfs-2.6 mountinfo

Re: vfs-2.6 mountinfo

[Al Viro]

On Mon, Mar 31, 2008 at 04:02:47PM +0200, Miklos Szeredi wrote:
> Some hunks from "[patch 4/7] vfs: mountinfo: add mount peer group ID"
> seems to have accidentally leaked into "[PATCH] teach seq_file to
> discard entries", affecting bisectability.

Ugh...  Will fix; thanks for spotting - I wonder how that had happened...

> And in "[patch 3/7] vfs: mountinfo: add mount ID" allocation is *not*
> serialized by namespace_sem on the vfs_kern_mount() call path, so this
> is racy AFAICS:

*hrm*

Right you are ;-/  I really don't like the look of that - the real question
here is whether we want vfsmount IDs to exist through the entire lifetime
of vfsmount.  If we do, then we need that (and use of vfsmount_lock in
free_vfsmnt() path as it is done now); if not...  I'm still tempted to
move allocation to the same place where we attach the damn thing to
some tree...

Anyway, retry variant will do for now, but I still wonder whether it's
really right long-term...  Do we want vfsmount IDs to have any exposure
other than that in mountinfo?