Re: [PATCH for-4.16 2/3] drivers: change struct device_driver::coredump() return type to void

[Greg Kroah-Hartman]

On Fri, Apr 06, 2018 at 09:35:35PM +0200, Arend van Spriel wrote:
> Op vr 6 apr. 2018 4:46 PM schreef Greg Kroah-Hartman
> <gregkh@xxxxxxxxxxxxxxxxxxx>:
> >
> > On Fri, Apr 06, 2018 at 12:13:38PM +0200, Arend van Spriel wrote:
> > > On Sat, Mar 24, 2018 at 10:04 AM, Greg Kroah-Hartman
> > > <gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
> > > > On Sat, Mar 24, 2018 at 09:50:05AM +0100, Arend van Spriel wrote:
> > > >> On Fri, Mar 23, 2018 at 5:55 PM, Greg Kroah-Hartman
> > > >> <gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
> > > >> > On Thu, Mar 15, 2018 at 10:55:24AM +0100, Arend van Spriel wrote:
> > > >> >> Upon submitting a patch for mwifiex [1] it was discussed whether this
> > > >> >> callback function could fail. To keep things simple there is no need
> > > >> >> for the error code so the driver can do the task synchronous or not
> > > >> >> without worries. Currently the device driver core already ignores the
> > > >> >> return value so changing it to void.
> > > >> >>
> > > >> >> [1] https://patchwork.kernel.org/patch/10231933/
> > > >> >>
> > > >> >> Signed-off-by: Arend van Spriel <aspriel@xxxxxxxxx>
> > > >> >> ---
> > > >> >>  include/linux/device.h | 5 ++++-
> > > >> >>  1 file changed, 4 insertions(+), 1 deletion(-)
> > > >> >>
> > > >> >> diff --git a/include/linux/device.h b/include/linux/device.h
> > > >> >> index b093405..f08c25b 100644
> > > >> >> --- a/include/linux/device.h
> > > >> >> +++ b/include/linux/device.h
> > > >> >> @@ -256,6 +256,9 @@ enum probe_type {
> > > >> >>   *           automatically.
> > > >> >>   * @pm:              Power management operations of the device which matched
> > > >> >>   *           this driver.
> > > >> >> + * @coredump:        Called when sysfs entry is written to. The device driver
> > > >> >> + *           is expected to call the dev_coredump API resulting in a
> > > >> >> + *           uevent.
> > > >> >>   * @p:               Driver core's private data, no one other than the driver
> > > >> >>   *           core can touch this.
> > > >> >>   *
> > > >> >> @@ -287,7 +290,7 @@ struct device_driver {
> > > >> >>       const struct attribute_group **groups;
> > > >> >>
> > > >> >>       const struct dev_pm_ops *pm;
> > > >> >> -     int (*coredump) (struct device *dev);
> > > >> >> +     void (*coredump) (struct device *dev);
> > > >> >
> > > >> > Isn't this going to cause build warnings now?  Are there no users of
> > > >> > this callback function yet?
> > > >>
> > > >> Hi Greg,
> > > >>
> > > >> I submitted driver patches for the 4.17 kernel and from that
> > > >> discussion we concluded it would be good to change to void return
> > > >> type. So those driver patches were dropped. The caller of the callback
> > > >> in drivers/base/dd.c does not use the return value so from that side
> > > >> there is no issue. So my motivation for asking to consider this for
> > > >> 4.16 is so I can resubmit the driver patches for 4.17 if there is
> > > >> still time before the merge window.
> > > >
> > > > It's too late for 4.16 for this, and I would queue it up in my tree now
> > > > but I don't want to cause any build warnings in linux-next from it.  So
> > > > how about I submit something like this right after 4.17-rc1 is out,
> > > > where the function signature is changed _and_ all definitions of that
> > > > function are changed at the same time to keep everything sane at once?
> > > >
> > > > Can you send me such a patch right before -rc1 is out base on Linus's
> > > > tree?  That should give everyone enough time to get the things merged,
> > > > right?
> > > >
> > > > Or is there no in-flight patches to use this yet, and I can queue it up
> > > > now for -rc1 as no build warnings will happen?
> > >
> > > Hi Greg,
> > >
> > > Are we good regarding this patch. I have assured there are not
> > > in-flight patches.
> >
> > All of my stuff is now in Linus's tree, so check there :)
> 
> Hi Greg,
> 
> That should have been obvious to me with merge window. Anyway, I
> checked and it seems this particular patch got lost somehow. The other
> two patches in the series are in Linus's tree. There was only one
> in-flight patch in bt-next and had it removed with you on Cc:.
> Probably got lost in your daily email storm :-p

Ah, sorry, now I remember.  Yeah, this is long-gone from my tree, care
to resend this and I'll get it merged after 4.17-rc1 is out?

thanks,

greg k-h