Re: [PATCH 7/9] s390/block/dcssblk: add error handling support for add_disk()

[Luis Chamberlain]

On Fri, Sep 03, 2021 at 04:08:48PM +0200, Heiko Carstens wrote:
> On Thu, Sep 02, 2021 at 10:41:03AM -0700, Luis Chamberlain wrote:
> > We never checked for errors on add_disk() as this function
> > returned void. Now that this is fixed, use the shiny new
> > error handling.
> > 
> > Signed-off-by: Luis Chamberlain <mcgrof@xxxxxxxxxx>
> > ---
> >  drivers/s390/block/dcssblk.c | 4 +++-
> >  1 file changed, 3 insertions(+), 1 deletion(-)
> > 
> > diff --git a/drivers/s390/block/dcssblk.c b/drivers/s390/block/dcssblk.c
> > index 5be3d1c39a78..b0fd5009a12e 100644
> > --- a/drivers/s390/block/dcssblk.c
> > +++ b/drivers/s390/block/dcssblk.c
> > @@ -696,7 +696,9 @@ dcssblk_add_store(struct device *dev, struct device_attribute *attr, const char
> >  	}
> >  
> >  	get_device(&dev_info->dev);
> > -	device_add_disk(&dev_info->dev, dev_info->gd, NULL);
> > +	rc = device_add_disk(&dev_info->dev, dev_info->gd, NULL);
> > +	if (rc)
> > +		goto put_dev;
> 
> This looks not correct to me. We seem to have now in case of an error:
> 
> - reference count imbalance (= memory leak)
> - dax cleanup is missing

Care to provide an alternative?

  Luis