On Mon, Sep 20, 2021 at 12:30 AM Christoph Hellwig <hch@xxxxxx> wrote: > > The proper API is to pass the groups to device_add_disk, but the code > used to also allow groups being set before calling *add_disk. Warn > about that but keep the group pointer intact for now so that it can > be removed again after a grace period. > > Signed-off-by: Christoph Hellwig <hch@xxxxxx> > Fixes: 52b85909f85d ("block: fold register_disk into device_add_disk") > --- > block/genhd.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/block/genhd.c b/block/genhd.c > index 7b6e5e1cf9564..409cf608cc5bd 100644 > --- a/block/genhd.c > +++ b/block/genhd.c > @@ -439,7 +439,8 @@ int device_add_disk(struct device *parent, struct gendisk *disk, > dev_set_uevent_suppress(ddev, 1); > > ddev->parent = parent; > - ddev->groups = groups; > + if (!WARN_ON_ONCE(ddev->groups)) > + ddev->groups = groups; That feels too compact to me, and dev_WARN_ONCE() might save someone a git blame to look up the reason for the warning: dev_WARN_ONCE(parent, ddev->groups, "unexpected pre-populated attribute group\n"); if (!ddev->groups) ddev->groups = groups; ...but not a deal breaker. Either way you can add: Reviewed-by: Dan Williams <dan.j.williams@xxxxxxxxx> Jens, I'm ok for the final spin of this series to go through block.git since the referenced commits in Fixes: went that route, just let me know if you want me to take them.