Re: [PATCH] Fix __d_path for lazy unmounts

[John Johansen <john.johansen@canonical.com>]

john.johansen@canonical.com wrote:
> From: John Johansen <john.johansen@canonical.com>
> 
> When __d_path() hits a lazily unmounted mount point, it tries to prepend
> the name of the lazily unmounted dentry to the path name.  It gets this wrong,
> and also overwrites the slash that separates the name from the following
> pathname component. This patch fixes that; if a process was in directory
> /foo/bar and /foo got lazily unmounted, the old result was ``foobar'' (note the
> missing slash), while the new result with this patch is ``/foo/bar''.
> 
It seems I left out the basic test for this.  From a shell you can do

> mkdir /tmp/foo
> sudo mount --bind /home/jj /tmp/foo   #substitute /home/jj as you wish
> cd /tmp/foo/bar       # assumes /home/jj/bar exists
> /bin/pwd
/tmp/foo/bar
> sudo umount -l /tmp/foo
> /bin/pwd
jjbar
> > cd ..
> > /bin/pwd
jj