Il giorno mar 14 giu 2022 alle ore 17:11 Andy Shevchenko <andy.shevchenko@xxxxxxxxx> ha scritto: > > On Tue, Jun 14, 2022 at 2:15 PM Andrea Merello <Andrea.Merello@xxxxxx> wrote: > > ... > > > >> >> + devm_add_action_or_reset(priv->dev, bno055_debugfs_remove, priv->debugfs); > > >> > > > >> >Shouldn't we report the potential error here? It's not directly > > >> >related to debugfs, but something which is not directly related. > > >> > > >> The error eventually comes out from something that has nothing to do with debugs per se (i.e. the devm stuff), but it will only affect debugfs indeed. > > >> > > >> Assuming that we don't want to make the whole driver fail in case debugfs stuff fails (see last part of the comment above debugfs_create_file() implementation), and given that the devm_add_action_or_reset(), should indeed "reset" in case of failure (i.e. we should be in a clean situation anyway), I would say it should be OK not to propagate the error and let things go on. > > > > > >As I said, it's not directly related to debugfs. Here is the resource > > >leak possible or bad things happen if you probe the driver, that fails > > >to add this call for removal, remove it, and try to insert again, in > > >such case the debugfs will be stale. > > > > Hum, I would say this shouldn't ever happen: AFAICS devm_add_action_or_reset() is a wrapper around devm_add_action() and it's purpose is exactly to add a check for failure; devm_add_action_or_reset() immediately invokes the action handler in case devm_add_action() fails. IOW in case of failure to add the devm stuff, the debugfs file is removed immediately and it shouldn't cause any mess with next times probe()s; just the driver will go on without the debugfs file being here. > > > > I think this is the point of using devm_add_action_or_reset() instead of dev_add_action() indeed, or am I missing something? > > Reading that code again and I think you are right, so dev_warn() will > be sufficient to show that we fail. OTOH, what is the point of adding > a resource for the failed debugfs call? Ah, you are right here: I'll make the call to devm_add_action_or_reset() conditional to success of debugfs_create_file(). In case any of the two fails we can also warn the user. > -- > With Best Regards, > Andy Shevchenko
