Messages in this thread | | | Date | Tue, 6 Jul 2021 14:14:45 +0200 | From | Uwe Kleine-König <> | Subject | Re: [PATCH] bus: Make remove callback return void |
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On Tue, Jul 06, 2021 at 01:17:37PM +0200, Cornelia Huck wrote: > On Tue, Jul 06 2021, Cornelia Huck <cohuck@redhat.com> wrote: > > > On Tue, Jul 06 2021, Uwe Kleine-König <u.kleine-koenig@pengutronix.de> wrote: > > > >> The driver core ignores the return value of this callback because there > >> is only little it can do when a device disappears. > >> > >> This is the final bit of a long lasting cleanup quest where several > >> buses were converted to also return void from their remove callback. > >> Additionally some resource leaks were fixed that were caused by drivers > >> returning an error code in the expectation that the driver won't go > >> away. > >> > >> With struct bus_type::remove returning void it's prevented that newly > >> implemented buses return an ignored error code and so don't anticipate > >> wrong expectations for driver authors. > > > > Yay! > > > >> > >> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> > >> --- > >> Hello, > >> > >> this patch depends on "PCI: endpoint: Make struct pci_epf_driver::remove > >> return void" that is not yet applied, see > >> https://lore.kernel.org/r/20210223090757.57604-1-u.kleine-koenig@pengutronix.de. > >> > >> I tested it using allmodconfig on amd64 and arm, but I wouldn't be > >> surprised if I still missed to convert a driver. So it would be great to > >> get this into next early after the merge window closes. > > > > I'm afraid you missed the s390-specific busses in drivers/s390/cio/ > > (css/ccw/ccwgroup).
:-\
> The change for vfio/mdev looks good. > > The following should do the trick for s390; not sure if other > architectures have easy-to-miss busses as well. > > diff --git a/drivers/s390/cio/ccwgroup.c b/drivers/s390/cio/ccwgroup.c > index 9748165e08e9..a66f416138ab 100644 > --- a/drivers/s390/cio/ccwgroup.c > +++ b/drivers/s390/cio/ccwgroup.c > @@ -439,17 +439,15 @@ module_exit(cleanup_ccwgroup); > > /************************** driver stuff ******************************/ > > -static int ccwgroup_remove(struct device *dev) > +static void ccwgroup_remove(struct device *dev) > { > struct ccwgroup_device *gdev = to_ccwgroupdev(dev); > struct ccwgroup_driver *gdrv = to_ccwgroupdrv(dev->driver); > > if (!dev->driver) > - return 0; > + return;
This is fine to be squashed into my patch. In the long run: in a remove callback dev->driver cannot be NULL, so this if could go away.
> if (gdrv->remove) > gdrv->remove(gdev); > - > - return 0; > } > > static void ccwgroup_shutdown(struct device *dev) > diff --git a/drivers/s390/cio/css.c b/drivers/s390/cio/css.c > index a974943c27da..ebc321edba51 100644 > --- a/drivers/s390/cio/css.c > +++ b/drivers/s390/cio/css.c > @@ -1371,15 +1371,14 @@ static int css_probe(struct device *dev) > return ret; > } > > -static int css_remove(struct device *dev) > +static void css_remove(struct device *dev) > { > struct subchannel *sch; > - int ret; > > sch = to_subchannel(dev); > - ret = sch->driver->remove ? sch->driver->remove(sch) : 0; > + if (sch->driver->remove) > + sch->driver->remove(sch);
Maybe the return type for this function pointer can be changed to void, too.
I will add these changes to a v2 that I plan to send out after the dust settles some more.
Thanks Uwe
-- Pengutronix e.K. | Uwe Kleine-König | Industrial Linux Solutions | https://www.pengutronix.de/ | [unhandled content-type:application/pgp-signature] | |