On Tue, Jun 08, 2021 at 07:19:33AM +0100, Christoph Hellwig wrote: > On Mon, Jun 07, 2021 at 09:55:47PM -0300, Jason Gunthorpe wrote: > > This is intended as a replacement API for device_bind_driver(). It has at > > least the following benefits: > > > > - Internal locking. Few of the users of device_bind_driver() follow the > > locking rules > > > > - Calls device driver probe() internally. Notably this means that devm > > support for probe works correctly as probe() error will call > > devres_release_all() > > > > - struct device_driver -> dev_groups is supported > > > > - Simplified calling convention, no need to manually call probe(). > > Btw, it would be nice to convert at least one existing user of > device_bind_driver to show this. Also maybe Cc all maintainers of > subsystems using device_bind_driver so that they get a headsup and > maybe quickly move over? Sure. I would do the MDIO phy, though I cann't test that code, I'm at least familiar with it.. > > @@ -1077,6 +1079,7 @@ int device_driver_attach(struct device_driver *drv, struct device *dev) > > return -EAGAIN; > > return ret; > > } > > +EXPORT_SYMBOL_GPL(device_driver_attach); > > Ok, this means my earlier suggestions of a locked driver_probe_device > helper needs a different name as we really don't want to expose flags > and always return -EAGAIN here. So maybe rename driver_probe_device > to __driver_probe_device, have a driver_probe_device around it that > does the locking and keep device_driver_attach for the newly exported > API. I put the squashing to -EAGAIN here specifically because of this export. EPROBE_DEFER should not be returned to userspace and if I leak it out to drivers at this point then one of them will eventually do it wrong, as we saw already in sysfs bind_store Jason
