• Andrey Vagin's avatar
    proc: show mnt_id in /proc/pid/fdinfo · 49d063cb
    Andrey Vagin authored
    
    
    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.
    
    $ ls -l /proc/1/fd/1
    lrwx------ 1 root root 64 Mar 19 23:54 /proc/1/fd/1 -> /dev/null
    
    $ cat /proc/1/fdinfo/1
    pos:	0
    flags:	0100002
    mnt_id:	16
    
    $ cat /proc/1/mountinfo | grep ^16
    16 32 0:4 / /dev rw,nosuid shared:2 - devtmpfs devtmpfs rw,size=1013356k,nr_inodes=253339,mode=755
    Signed-off-by: default avatarAndrey Vagin <avagin@openvz.org>
    Acked-by: default avatarPavel Emelyanov <xemul@parallels.com>
    Acked-by: default avatarCyrill Gorcunov <gorcunov@openvz.org>
    Cc: Rob Landley <rob@landley.net>
    Cc: Al Viro <viro@zeniv.linux.org.uk>
    Cc: Oleg Nesterov <oleg@redhat.com>
    Cc: "Eric W. Biederman" <ebiederm@xmission.com>
    Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
    Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
    49d063cb
proc.txt 79.7 KB