Re: [PATCH 2/10] sysdev: add error check in sysdev_register()

Akinobu Mita
2007-07-16T16:18:32Z

2007/7/17, Cornelia Huck <cornelia.huck@de.ibm.com>:
> On Mon, 16 Jul 2007 22:51:38 +0900,
> Akinobu Mita <akinobu.mita@gmail.com> wrote:
>
> > This patch enables to catch the errors returned by add() procedure of
> > sysdev driver in sysdev_register.
>
> > @@ -253,23 +254,50 @@ int sysdev_register(struct sys_device *
> >
> > /* Notify global drivers */
> > list_for_each_entry(drv, &sysdev_drivers, entry) {
> > - if (drv->add)
> > - drv->add(sysdev);
> > + if (drv->add) {
> > + error = drv->add(sysdev);
> > + if (error)
> > + goto error_sysdev;
> > + }
> > + added_sysdev++;
> > }
>
> This looks asymmetric to me. Imagine we have a device/driver
> combination for which drv->add will return -ESOMEERROR. Now, it depends
> on the order:
>
> 1. The device is registered when the driver is already registered:
> registration of the device will fail.
>
> 2. The driver is registered when the device is already registered:
> driver registration will succeed, and the device will stay registered.
>
> I'm not sure if that is what we really want.

Thanks, I didn't realize the asymmetry.
I think we need to add same check to sysdev_driver_register().
But I need to check every sysdev driver's add() functions before
making this change. So this patch dropped from this series of patches
for now.