EPROBE_DEFER is an internal kernel error code and it should not be leaked to userspace via the bind_store() sysfs. Userspace doesn't have this constant and cannot understand it. Further, it doesn't really make sense to have userspace trigger a deferred probe via bind_store(), which could eventually succeed, while simultaneously returning an error back. Resolve this by splitting driver_probe_device so that the version used by the sysfs binding that turns EPROBE_DEFER into -EAGAIN, while the one used for internally binding keeps the error code, and calls driver_deferred_probe_add where needed. This also allows to nicely split out the defer_all_probes / probe_count checks so that they actually allow for full device_{block,unblock}_probing protection while not bothering the sysfs bind case. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Link: https://lore.kernel.org/r/20210617142218.1877096-5-hch@lst.de Signed-off-by: Alex Williamson <alex.williamson@redhat.com>