[CRIU] [PATCH] mnt: Map opts.root to match root mountpoints in stat resolving

[Cyrill Gorcunov]

On Fri, Nov 27, 2015 at 8:25 PM, Cyrill Gorcunov <gorcunov at openvz.org> wrote:
> When opening mountpoint with __open_mountpoint() helper we try
> to detect potential overmounts comparing devices obtained
> from stat() call with one got from image or mountinfo parsing.
>
> This works well for static cases while underlied device doesn't
> change its device ID. But device can easily change in case
> of container's migration causing restore to fail (in particular
> we noticed this problem trying to restore an inotify object which
> bound to device:inode pair when opening it via file handle).
>
> Thus for a simple case when only toplevel root is migrating
> or changing lets try to handle it gracefully -- if opts.root
> passed we remember the new root device ID and then in
> __open_mountpoint() test if the changed device can still
> be used.
>
> https://jira.sw.ru/browse/PSBM-41610
>
> Signed-off-by: Cyrill Gorcunov <gorcunov at openvz.org>

Ping! Guys, any opinion?