Messages in this thread | | | Date | Mon, 8 Feb 2016 08:35:27 -0800 | From | Greg Kroah-Hartman <> | Subject | Re: [RFC PATCH 1/3] debugfs: fix automount inode i_nlink references |
| |
On Mon, Feb 08, 2016 at 11:28:52AM +0100, Roman Peniaev wrote: > On Mon, Feb 8, 2016 at 7:38 AM, Greg Kroah-Hartman > <gregkh@linuxfoundation.org> wrote: > > On Thu, Dec 10, 2015 at 01:47:12PM +0100, Roman Pen wrote: > >> Directory inodes should start off with i_nlink == 2 (for "." entry). > >> Of course the same rule should be applied to automount dentries for > >> child and parent inodes as well. > >> > >> Also now automount dentry does fsnotify_mkdir. > >> > >> Without this patch kernel complains when sees i_nlink == 0: > > > > How can the kernel see this? What did you do to trigger this? > > Yes, sorry, I had to be more precise on this. > That happens on unlinking of automount dentry. > > Easily can be reproduced: > > autom = debugfs_create_automount("automount", parentd, vfsmount_cb, data); > BUG_ON(IS_ERR_OR_NULL(autom)); > debugfs_remove(autom); > > You will immediately see one warning on attempt to drop_nlink() (which is zero) > for automount dentry.
Why don't we see this "in the wild" today with the one user of this function?
> The second warning happens when you unlink 'parentd', because > debugfs_create_automount() did not increase the nlink for parent > inode. > > Do I need to resend this patch with more precise description?
Yes, please fix up and resend as a stand-alone patch, as it is independant of your other proposal.
And take off the "RFC" marking, I can never apply a patch with that type of marking as you obviously don't think it is good enough to be merged, so why would I? :)
thanks,
greg k-h
| |