Mathieu Desnoyers wrote: > Now that alloc_dax() returns ERR_PTR(-EOPNOTSUPP) rather than NULL, > the callers do not have to handle NULL return values anymore. > > Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxxxx> > Cc: Alasdair Kergon <agk@xxxxxxxxxx> > Cc: Mike Snitzer <snitzer@xxxxxxxxxx> > Cc: Mikulas Patocka <mpatocka@xxxxxxxxxx> > Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> > Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> > Cc: Dan Williams <dan.j.williams@xxxxxxxxx> > Cc: Vishal Verma <vishal.l.verma@xxxxxxxxx> > Cc: Dave Jiang <dave.jiang@xxxxxxxxx> > Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx> > Cc: Arnd Bergmann <arnd@xxxxxxxx> > Cc: Russell King <linux@xxxxxxxxxxxxxxx> > Cc: linux-arch@xxxxxxxxxxxxxxx > Cc: linux-cxl@xxxxxxxxxxxxxxx > Cc: linux-fsdevel@xxxxxxxxxxxxxxx > Cc: linux-mm@xxxxxxxxx > Cc: linux-xfs@xxxxxxxxxxxxxxx > Cc: dm-devel@xxxxxxxxxxxxxxx > Cc: nvdimm@xxxxxxxxxxxxxxx > --- > drivers/nvdimm/pmem.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c > index f1d9f5c6dbac..e9898457a7bd 100644 > --- a/drivers/nvdimm/pmem.c > +++ b/drivers/nvdimm/pmem.c > @@ -558,8 +558,8 @@ static int pmem_attach_disk(struct device *dev, > disk->bb = &pmem->bb; > > dax_dev = alloc_dax(pmem, &pmem_dax_ops); > - if (IS_ERR_OR_NULL(dax_dev)) { > - rc = IS_ERR(dax_dev) ? PTR_ERR(dax_dev) : -EOPNOTSUPP; > + if (IS_ERR(dax_dev)) { > + rc = PTR_ERR(dax_dev); Oh... I see you cleanup what I was talking about later in the series. For my taste I don't like to see tech-debt added and then removed later in the series. The whole series would appear to get smaller by removing the alloc_dax() returning NULL case from the beginning, and then doing the EOPNOTSUPP fixups. ...repeat this comment for patch 10, 11, 12.