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

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <697020c95d699_1a50d4100e9@iweiny-mobl.notmuch>
Date: Tue, 20 Jan 2026 18:41:45 -0600
From: Ira Weiny <ira.weiny@...el.com>
To: Neeraj Kumar <s.neeraj@...sung.com>, <linux-cxl@...r.kernel.org>,
	<nvdimm@...ts.linux.dev>, <linux-kernel@...r.kernel.org>,
	<gost.dev@...sung.com>
CC: <a.manzanares@...sung.com>, <vishak.g@...sung.com>,
	<neeraj.kernel@...il.com>, Neeraj Kumar <s.neeraj@...sung.com>
Subject: Re: [PATCH V5 05/17] nvdimm/label: Skip region label during ns label
 DPA reservation

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@...el.com>
> Signed-off-by: Neeraj Kumar <s.neeraj@...sung.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@...el.com>

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