| 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
| ||
|
Message-ID: <20260109115128.sgu2x2537jno7tug@test-PowerEdge-R740xd>
Date: Fri, 9 Jan 2026 17:21:28 +0530
From: Neeraj Kumar <s.neeraj@...sung.com>
To: Jonathan Cameron <jonathan.cameron@...wei.com>
Cc: linux-cxl@...r.kernel.org, nvdimm@...ts.linux.dev,
linux-kernel@...r.kernel.org, gost.dev@...sung.com,
a.manzanares@...sung.com, vishak.g@...sung.com, neeraj.kernel@...il.com,
cpgs@...sung.com
Subject: Re: [PATCH V4 03/17] nvdimm/label: Add namespace/region label
support as per LSA 2.1
On 17/12/25 02:31PM, Jonathan Cameron wrote:
>On Wed, 19 Nov 2025 13:22:41 +0530
>Neeraj Kumar <s.neeraj@...sung.com> wrote:
>
>> Modify __pmem_label_update() to update region labels into LSA
>>
>> CXL 3.2 Spec mentions CXL LSA 2.1 Namespace Labels at section 9.13.2.5
>> Modified __pmem_label_update() using setter functions to update
>> namespace label as per CXL LSA 2.1
>>
>> Create export routine nd_region_label_update() used for creating
>> region label into LSA. It will be used later from CXL subsystem
>>
>> Signed-off-by: Neeraj Kumar <s.neeraj@...sung.com>
>Hi Neeraj,
>
>A few things inline from a fresh read.
>
>Thanks,
>
>Jonathan
>
>> ---
>> drivers/nvdimm/label.c | 360 ++++++++++++++++++++++++++------
>> drivers/nvdimm/label.h | 17 +-
>> drivers/nvdimm/namespace_devs.c | 25 ++-
>> drivers/nvdimm/nd.h | 66 ++++++
>> include/linux/libnvdimm.h | 8 +
>> 5 files changed, 406 insertions(+), 70 deletions(-)
>>
>> diff --git a/drivers/nvdimm/label.c b/drivers/nvdimm/label.c
>> index 0a9b6c5cb2c3..0d587a5b9f7e 100644
>> --- a/drivers/nvdimm/label.c
>> +++ b/drivers/nvdimm/label.c
>
>
>
>
>> @@ -978,7 +1132,8 @@ static int __pmem_label_update(struct nd_region *nd_region,
>> return rc;
>> }
>
>> int nd_pmem_namespace_label_update(struct nd_region *nd_region,
>> struct nd_namespace_pmem *nspm, resource_size_t size)
>> {
>> @@ -1075,6 +1253,7 @@ int nd_pmem_namespace_label_update(struct nd_region *nd_region,
>> for (i = 0; i < nd_region->ndr_mappings; i++) {
>> struct nd_mapping *nd_mapping = &nd_region->mapping[i];
>> struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
>> + int region_label_cnt = 0;
>
>Always initialized anyway before use I think. So no need to do it here.
Fixed it in V5
>
>> struct resource *res;
>> int count = 0;
>>
>> @@ -1090,12 +1269,20 @@ int nd_pmem_namespace_label_update(struct nd_region *nd_region,
>> count++;
>> WARN_ON_ONCE(!count);
>>
>> - rc = init_labels(nd_mapping, count);
>> + region_label_cnt = find_region_label_count(nd_mapping);
>> + /*
>> + * init_labels() scan labels and allocate new label based
>> + * on its second parameter (num_labels). Therefore to
>> + * allocate new namespace label also include previously
>> + * added region label
>> + */
>> + rc = init_labels(nd_mapping, count + region_label_cnt,
>> + NS_LABEL_TYPE);
>> if (rc < 0)
>> return rc;
>>
>> rc = __pmem_label_update(nd_region, nd_mapping, nspm, i,
>> - NSLABEL_FLAG_UPDATING);
>> + NSLABEL_FLAG_UPDATING, NS_LABEL_TYPE);
>> if (rc)
>> return rc;
>> }
>
>> +int nd_pmem_region_label_update(struct nd_region *nd_region)
>> +{
>> + int i, rc;
>> +
>> + for (i = 0; i < nd_region->ndr_mappings; i++) {
>> + struct nd_mapping *nd_mapping = &nd_region->mapping[i];
>> + struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
>> + int region_label_cnt = 0;
>
>Seems to always be initialized before use anyway so no need to do it here.
Fixed it in V5
>
>> +
>> + /* No need to update region label for non cxl format */
>> + if (!ndd->cxl)
>> + return 0;
>> +
>> + region_label_cnt = find_region_label_count(nd_mapping);
>> + rc = init_labels(nd_mapping, region_label_cnt + 1,
>> + RG_LABEL_TYPE);
>> + if (rc < 0)
>> + return rc;
>> +
>> + rc = __pmem_label_update(nd_region, nd_mapping, NULL, i,
>> + NSLABEL_FLAG_UPDATING, RG_LABEL_TYPE);
>> + if (rc)
>> + return rc;
>> + }
>> +
>> + /* Clear the UPDATING flag per UEFI 2.7 expectations */
>> + for (i = 0; i < nd_region->ndr_mappings; i++) {
>> + struct nd_mapping *nd_mapping = &nd_region->mapping[i];
>> + struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
>> +
>> + WARN_ON_ONCE(!ndd->cxl);
>> + rc = __pmem_label_update(nd_region, nd_mapping, NULL, i, 0,
>> + RG_LABEL_TYPE);
>> if (rc)
>> return rc;
>> }
>
>> diff --git a/drivers/nvdimm/namespace_devs.c b/drivers/nvdimm/namespace_devs.c
>> index 43fdb806532e..b1abbe602a5e 100644
>> --- a/drivers/nvdimm/namespace_devs.c
>> +++ b/drivers/nvdimm/namespace_devs.c
>> @@ -232,6 +232,18 @@ static ssize_t __alt_name_store(struct device *dev, const char *buf,
>> return rc;
>> }
>>
>> +int nd_region_label_update(struct nd_region *nd_region)
>> +{
>> + int rc;
>> +
>> + nvdimm_bus_lock(&nd_region->dev);
>> + rc = nd_pmem_region_label_update(nd_region);
>> + nvdimm_bus_unlock(&nd_region->dev);
>
>In line with much of the nvdimm stuff I'd use guard and save a couple of lines.
>
> guard(nvdimm_bus)(&nd_region->dev);
> return nd_pmem_region_label_update(nd_region);
>
Fixed it in V5
>> +
>> + return rc;
>> +}
>> +EXPORT_SYMBOL_GPL(nd_region_label_update);
>
>> diff --git a/drivers/nvdimm/nd.h b/drivers/nvdimm/nd.h
>> index f631bd84d6f0..5fd69c28ffe7 100644
>> --- a/drivers/nvdimm/nd.h
>> +++ b/drivers/nvdimm/nd.h
>> @@ -14,6 +14,9 @@
>> #include <linux/nd.h>
>> #include "label.h"
>>
>> +extern uuid_t cxl_namespace_uuid;
>> +extern uuid_t cxl_region_uuid;
>> +
>> enum {
>> /*
>> * Limits the maximum number of block apertures a dimm can
>> @@ -295,6 +298,67 @@ static inline const u8 *nsl_uuid_raw(struct nvdimm_drvdata *ndd,
>> return nd_label->efi.uuid;
>> }
>>
>> +static inline void nsl_set_type(struct nvdimm_drvdata *ndd,
>> + struct nd_namespace_label *ns_label)
>> +{
>> + if (!(ndd->cxl && ns_label))
>> + return;
>> +
>> + uuid_copy((uuid_t *)ns_label->cxl.type, &cxl_namespace_uuid);
>
>uuid_import() perhaps more appropriate given it is coming(I think)
>from a __u8 &.
>
Yes we can avoid extra typecasting in uuid_copy using uuid_export().
Actually cxl_namespace_uuid is of type uuid_t and ns_label->cxl.type is of type __u8
So export_uuid() is appropriate here than uuid_inport()
I have fixed it in V5
>> +}
>> +
>
>
>> +
>> +static inline bool is_region_label(struct nvdimm_drvdata *ndd,
>> + union nd_lsa_label *lsa_label)
>> +{
>> + uuid_t *region_type;
>> +
>> + if (!ndd->cxl)
>> + return false;
>> +
>> + region_type = (uuid_t *) lsa_label->region_label.type;
>> + return uuid_equal(&cxl_region_uuid, region_type)
>
>I'd match style of next function and not have the local variable.
>
> return uuid_equal(&cxl_region_uuid,
> (uuid_t *)lsa_label->region_label.type);
Fixed it in V5
>> +}
>> +
>> +static inline bool
>> +region_label_uuid_equal(struct cxl_region_label *region_label,
>> + const uuid_t *uuid)
>> +{
>> + return uuid_equal((uuid_t *) region_label->uuid, uuid);
>
>Dave pointed out that there shouldn't be a space after the cast.
>Make sure you catch all of these.
>
Fixed it in V5
>> +}
>> +
>> +static inline u64
>> +region_label_get_checksum(struct cxl_region_label *region_label)
>> +{
>> + return __le64_to_cpu(region_label->checksum);
>> +}
>> +
>> +static inline void
>> +region_label_set_checksum(struct cxl_region_label *region_label,
>> + u64 checksum)
>> +{
>> + region_label->checksum = __cpu_to_le64(checksum);
>> +}
>
>Perhaps add a little justification to the patch description on why these
>get/set are helpful? Seems like just setting them directly would perhaps
>be fine as all call sites can see the structure definition anyway?
>
Thanks Jonathan, I have used them directly instead of extra setter function in V5
Regards,
Neeraj
Powered by blists - more mailing lists