Re: [PATCH V5 05/17] nvdimm/label: Skip region label during ns label DPA reservation

Ira Weiny
2026-01-21T00:38:38Z

Neeraj Kumar wrote:
> CXL 3.2 Spec mentions CXL LSA 2.1 Namespace Labels at section
> 9.13.2.5. If Namespace label is present in LSA during
> nvdimm_probe() then dimm-physical-address(DPA) reservation is
> required. But this reservation is not required by cxl region
> label. Therefore if LSA scanning finds any region label, skip it.
>
> Reviewed-by: Dave Jiang <dave.jiang@intel.com>
> Signed-off-by: Neeraj Kumar <s.neeraj@samsung.com>
> ---
> drivers/nvdimm/label.c | 8 ++++++++
> 1 file changed, 8 insertions(+)
>
> diff --git a/drivers/nvdimm/label.c b/drivers/nvdimm/label.c
> index 9854cb45fb62..169692dfa12c 100644
> --- a/drivers/nvdimm/label.c
> +++ b/drivers/nvdimm/label.c
> @@ -469,6 +469,14 @@ int nd_label_reserve_dpa(struct nvdimm_drvdata *ndd)
> lsa_label = to_lsa_label(ndd, slot);
> nd_label = &lsa_label->ns_label;
>
> + /*
> + * Skip region label. If LSA label is region label
^^^^^^^^^^^^^^^^^^
This is redundant
> + * then it don't require dimm-physical-address(DPA)
^^^^^
doesn't

> + * reservation. Whereas its required for namespace label
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
This is somewhat confusing and redundant
as well.

Simply say.

/*
* If the LSA label is a region label then it doesn't require a
* dimm-physical-address(DPA) reservation.
*/

With that.

Reviewed-by: Ira Weiny <ira.weiny@intel.com>

> + if (is_region_label(ndd, lsa_label))
> + continue;
> +
> if (!slot_valid(ndd, lsa_label, slot))
> continue;
>
> --
> 2.34.1
>
>