On Wed, Mar 24, 2021 at 10:01:42AM -0700, Dan Williams wrote:
> On Wed, Mar 24, 2021 at 9:52 AM Jason Gunthorpe <jgg@xxxxxxxxxx> wrote:
> >
> > On Wed, Mar 24, 2021 at 09:13:35AM -0700, Dan Williams wrote:
> >
> > > Which is just:
> > >
> > > device_initialize()
> > > dev_set_name()
> > >
> > > ...then the name is set as early as the device is ready to filled in
> > > with other details. Just checking for dev_set_name() failures does not
> > > move the api forward in my opinion.
> >
> > This doesn't work either as the release function must be set after
> > initialize but before dev_set_name(), otherwise we both can't and must
> > call put_device() after something like this fails.
>
> Ugh, true.
>
> >
> > I can't see an option other than bite the bullet and fix things.
> >
> > A static tool to look for these special lifetime rules around the
> > driver core would be nice.
>
> It would... it would also trip over the fact the core itself fails to
> check for dev_set_name() failures and also relies on !dev_name() as a
> check after-the-fact.
>
> That check is broken if the device was not zeroed on allocate.
If it's not zeroed on alloc then you'd probably run into problems much
earlier. For example, the dev->init_name chunk would probably crash.
if (dev->init_name) {
dev_set_name(dev, "%s", dev->init_name);
dev->init_name = NULL;
}
regards,
dan carpenter
