[PATCH v2 12/13] block: make __register_blkdev() return an error

[Luis Chamberlain]

On Wed, Nov 03, 2021 at 05:09:33PM +0100, Christoph Hellwig wrote:
> On Wed, Nov 03, 2021 at 05:21:56AM -0700, Luis Chamberlain wrote:
> > This makes __register_blkdev() return an error, and also changes the
> > probe() call to return an error as well.
> > 
> > We expand documentation for the probe call to ensure that if the block
> > device already exists we don't return on error on that condition. We do
> > this as otherwise we loose ability to handle concurrent requests if the
> > block device already existed.
> 
> I'm still not really sold on this - if the probe fails no bdev will
> be registered and the lookup will fail.  What is the benefit of
> propagating the exact error here?

Here's the thing, prober call a form of add_disk(), and so do we want
to always ignore the errors on probe? If so we should document why that
is sane then. I think this approach is a bit more sane though.

  Luis