Re: [PATCH v2 09/17] firmware: turris-mox-rwtm: Simplify debugfs code

["Marek Behún" <kabel@kernel.org>]

On Thu, 13 Jun 2024 22:37:39 +0200
Andy Shevchenko <andy.shevchenko@gmail.com> wrote:

> On Thu, Jun 13, 2024 at 6:11 PM Marek Behún <kabel@kernel.org> wrote:
> >
> > Simplify debugfs code: do not check for errors, as debugfs errors should
> > be ignored, and use devm action for dropping the debugfs directory.  
> 
> ...
> 
> > -static void rwtm_unregister_debugfs(struct mox_rwtm *rwtm)
> > +static void rwtm_register_debugfs(struct mox_rwtm *rwtm)
> >  {
> > -       debugfs_remove_recursive(rwtm->debugfs_root);
> > +       struct dentry *root;
> > +
> > +       root = debugfs_create_dir("turris-mox-rwtm", NULL);
> > +
> > +       devm_add_action_or_reset(rwtm->dev, rwtm_debugfs_release, root);  
> 
> This is incorrect. If devm_add_action() fails, the root will be removed...
> 
> > +       debugfs_create_file_unsafe("do_sign", 0600, root, rwtm, &do_sign_fops);  
> 
> ...and this most likely will use the dangling pointer.

OK, I will first creae the file and then add the action.