Re: [PATCH] proc: show mnt_id in fdinfo files

[Andrew Morton <akpm@linux-foundation.org>]

On Mon, 17 Mar 2014 15:50:13 +0400 Cyrill Gorcunov <gorcunov@gmail.com> wrote:

> On Mon, Mar 17, 2014 at 03:30:26PM +0400, Pavel Emelyanov wrote:
> > On 03/17/2014 02:39 PM, Andrey Vagin wrote:
> > > Currently we don't have a way how to determing from which mount point
> > > file has been opened. This information is required for proper dumping
> > > and restoring file descriptos due to presence of mount namespaces. It's
> > > possible, that two file descriptors are opened using the same paths, but
> > > one fd references mount point from one namespace while the other fd --
> > > from other namespace.
> > > 
> > > Cc: Al Viro <viro@zeniv.linux.org.uk>
> > > Cc: Oleg Nesterov <oleg@redhat.com>
> > > Cc: Andrew Morton <akpm@linux-foundation.org>
> > > Cc: Cyrill Gorcunov <gorcunov@openvz.org>
> > > Cc: Pavel Emelyanov <xemul@parallels.com>
> > > Signed-off-by: Andrey Vagin <avagin@openvz.org>
> > 
> > These IDs are already shown in the /proc/$pid/mountinfo, and for some FSs
> > can be obtained via path_to_handle_at(), so this patch just makes it work
> > for any FS and speeds things up.
> > 
> > Acked-by: Pavel Emelyanov <xemul@parallels.com>
> 
> I think Documentation/filesystems/proc.txt should be updated on top.

Yes please.

It would be nice to see example output in the changelog as well please.