2021-01-05 23:03:31

by Dan Williams

[permalink] [raw]
Subject: [PATCH] ACPI: NFIT: Fix flexible_array.cocci warnings

Julia and 0day report:

Zero-length and one-element arrays are deprecated, see
Documentation/process/deprecated.rst
Flexible-array members should be used instead.

However, a straight conversion to flexible arrays yields:

drivers/acpi/nfit/core.c:2276:4: error: flexible array member in a struct with no named members
drivers/acpi/nfit/core.c:2287:4: error: flexible array member in a struct with no named members

Instead, just use plain arrays not embedded a flexible arrays.

Cc: Denis Efremov <[email protected]>
Reported-by: kernel test robot <[email protected]>
Reported-by: Julia Lawall <[email protected]>
Signed-off-by: Dan Williams <[email protected]>
---
drivers/acpi/nfit/core.c | 75 +++++++++++++++++-----------------------------
1 file changed, 28 insertions(+), 47 deletions(-)

diff --git a/drivers/acpi/nfit/core.c b/drivers/acpi/nfit/core.c
index b11b08a60684..8c5dde628405 100644
--- a/drivers/acpi/nfit/core.c
+++ b/drivers/acpi/nfit/core.c
@@ -2269,40 +2269,24 @@ static const struct attribute_group *acpi_nfit_region_attribute_groups[] = {

/* enough info to uniquely specify an interleave set */
struct nfit_set_info {
- struct nfit_set_info_map {
- u64 region_offset;
- u32 serial_number;
- u32 pad;
- } mapping[0];
+ u64 region_offset;
+ u32 serial_number;
+ u32 pad;
};

struct nfit_set_info2 {
- struct nfit_set_info_map2 {
- u64 region_offset;
- u32 serial_number;
- u16 vendor_id;
- u16 manufacturing_date;
- u8 manufacturing_location;
- u8 reserved[31];
- } mapping[0];
+ u64 region_offset;
+ u32 serial_number;
+ u16 vendor_id;
+ u16 manufacturing_date;
+ u8 manufacturing_location;
+ u8 reserved[31];
};

-static size_t sizeof_nfit_set_info(int num_mappings)
-{
- return sizeof(struct nfit_set_info)
- + num_mappings * sizeof(struct nfit_set_info_map);
-}
-
-static size_t sizeof_nfit_set_info2(int num_mappings)
-{
- return sizeof(struct nfit_set_info2)
- + num_mappings * sizeof(struct nfit_set_info_map2);
-}
-
static int cmp_map_compat(const void *m0, const void *m1)
{
- const struct nfit_set_info_map *map0 = m0;
- const struct nfit_set_info_map *map1 = m1;
+ const struct nfit_set_info *map0 = m0;
+ const struct nfit_set_info *map1 = m1;

return memcmp(&map0->region_offset, &map1->region_offset,
sizeof(u64));
@@ -2310,8 +2294,8 @@ static int cmp_map_compat(const void *m0, const void *m1)

static int cmp_map(const void *m0, const void *m1)
{
- const struct nfit_set_info_map *map0 = m0;
- const struct nfit_set_info_map *map1 = m1;
+ const struct nfit_set_info *map0 = m0;
+ const struct nfit_set_info *map1 = m1;

if (map0->region_offset < map1->region_offset)
return -1;
@@ -2322,8 +2306,8 @@ static int cmp_map(const void *m0, const void *m1)

static int cmp_map2(const void *m0, const void *m1)
{
- const struct nfit_set_info_map2 *map0 = m0;
- const struct nfit_set_info_map2 *map1 = m1;
+ const struct nfit_set_info2 *map0 = m0;
+ const struct nfit_set_info2 *map1 = m1;

if (map0->region_offset < map1->region_offset)
return -1;
@@ -2361,22 +2345,22 @@ static int acpi_nfit_init_interleave_set(struct acpi_nfit_desc *acpi_desc,
return -ENOMEM;
import_guid(&nd_set->type_guid, spa->range_guid);

- info = devm_kzalloc(dev, sizeof_nfit_set_info(nr), GFP_KERNEL);
+ info = devm_kcalloc(dev, nr, sizeof(*info), GFP_KERNEL);
if (!info)
return -ENOMEM;

- info2 = devm_kzalloc(dev, sizeof_nfit_set_info2(nr), GFP_KERNEL);
+ info2 = devm_kcalloc(dev, nr, sizeof(*info2), GFP_KERNEL);
if (!info2)
return -ENOMEM;

for (i = 0; i < nr; i++) {
struct nd_mapping_desc *mapping = &ndr_desc->mapping[i];
- struct nfit_set_info_map *map = &info->mapping[i];
- struct nfit_set_info_map2 *map2 = &info2->mapping[i];
struct nvdimm *nvdimm = mapping->nvdimm;
struct nfit_mem *nfit_mem = nvdimm_provider_data(nvdimm);
- struct acpi_nfit_memory_map *memdev = memdev_from_spa(acpi_desc,
- spa->range_index, i);
+ struct nfit_set_info *map = &info[i];
+ struct nfit_set_info2 *map2 = &info2[i];
+ struct acpi_nfit_memory_map *memdev =
+ memdev_from_spa(acpi_desc, spa->range_index, i);
struct acpi_nfit_control_region *dcr = nfit_mem->dcr;

if (!memdev || !nfit_mem->dcr) {
@@ -2395,23 +2379,20 @@ static int acpi_nfit_init_interleave_set(struct acpi_nfit_desc *acpi_desc,
}

/* v1.1 namespaces */
- sort(&info->mapping[0], nr, sizeof(struct nfit_set_info_map),
- cmp_map, NULL);
- nd_set->cookie1 = nd_fletcher64(info, sizeof_nfit_set_info(nr), 0);
+ sort(info, nr, sizeof(*info), cmp_map, NULL);
+ nd_set->cookie1 = nd_fletcher64(info, sizeof(*info) * nr, 0);

/* v1.2 namespaces */
- sort(&info2->mapping[0], nr, sizeof(struct nfit_set_info_map2),
- cmp_map2, NULL);
- nd_set->cookie2 = nd_fletcher64(info2, sizeof_nfit_set_info2(nr), 0);
+ sort(info2, nr, sizeof(*info2), cmp_map2, NULL);
+ nd_set->cookie2 = nd_fletcher64(info2, sizeof(*info2) * nr, 0);

/* support v1.1 namespaces created with the wrong sort order */
- sort(&info->mapping[0], nr, sizeof(struct nfit_set_info_map),
- cmp_map_compat, NULL);
- nd_set->altcookie = nd_fletcher64(info, sizeof_nfit_set_info(nr), 0);
+ sort(info, nr, sizeof(*info), cmp_map_compat, NULL);
+ nd_set->altcookie = nd_fletcher64(info, sizeof(*info) * nr, 0);

/* record the result of the sort for the mapping position */
for (i = 0; i < nr; i++) {
- struct nfit_set_info_map2 *map2 = &info2->mapping[i];
+ struct nfit_set_info2 *map2 = &info2[i];
int j;

for (j = 0; j < nr; j++) {


2021-01-05 23:05:25

by Verma, Vishal L

[permalink] [raw]
Subject: Re: [PATCH] ACPI: NFIT: Fix flexible_array.cocci warnings

On Tue, 2021-01-05 at 13:03 -0800, Dan Williams wrote:
> Julia and 0day report:
>
>     Zero-length and one-element arrays are deprecated, see
>     Documentation/process/deprecated.rst
>     Flexible-array members should be used instead.
>
> However, a straight conversion to flexible arrays yields:
>
>     drivers/acpi/nfit/core.c:2276:4: error: flexible array member in a struct with no named members
>     drivers/acpi/nfit/core.c:2287:4: error: flexible array member in a struct with no named members
>
> Instead, just use plain arrays not embedded a flexible arrays.

This reads a bit awkwardly, maybe:

"Just use plain arrays instead of embedded flexible arrays."

Other than that, the patch looks looks good:
Reviewed-by: Vishal Verma <[email protected]>

>
> Cc: Denis Efremov <[email protected]>
> Reported-by: kernel test robot <[email protected]>
> Reported-by: Julia Lawall <[email protected]>
> Signed-off-by: Dan Williams <[email protected]>
> ---
>  drivers/acpi/nfit/core.c | 75 +++++++++++++++++-----------------------------
>  1 file changed, 28 insertions(+), 47 deletions(-)
>
> diff --git a/drivers/acpi/nfit/core.c b/drivers/acpi/nfit/core.c
> index b11b08a60684..8c5dde628405 100644
> --- a/drivers/acpi/nfit/core.c
> +++ b/drivers/acpi/nfit/core.c
> @@ -2269,40 +2269,24 @@ static const struct attribute_group *acpi_nfit_region_attribute_groups[] = {
>  
>
>
>
>  /* enough info to uniquely specify an interleave set */
>  struct nfit_set_info {
> - struct nfit_set_info_map {
> - u64 region_offset;
> - u32 serial_number;
> - u32 pad;
> - } mapping[0];
> + u64 region_offset;
> + u32 serial_number;
> + u32 pad;
>  };
>  
>
>
>
>  struct nfit_set_info2 {
> - struct nfit_set_info_map2 {
> - u64 region_offset;
> - u32 serial_number;
> - u16 vendor_id;
> - u16 manufacturing_date;
> - u8 manufacturing_location;
> - u8 reserved[31];
> - } mapping[0];
> + u64 region_offset;
> + u32 serial_number;
> + u16 vendor_id;
> + u16 manufacturing_date;
> + u8 manufacturing_location;
> + u8 reserved[31];
>  };
>  
>
>
>
> -static size_t sizeof_nfit_set_info(int num_mappings)
> -{
> - return sizeof(struct nfit_set_info)
> - + num_mappings * sizeof(struct nfit_set_info_map);
> -}
> -
> -static size_t sizeof_nfit_set_info2(int num_mappings)
> -{
> - return sizeof(struct nfit_set_info2)
> - + num_mappings * sizeof(struct nfit_set_info_map2);
> -}
> -
>  static int cmp_map_compat(const void *m0, const void *m1)
>  {
> - const struct nfit_set_info_map *map0 = m0;
> - const struct nfit_set_info_map *map1 = m1;
> + const struct nfit_set_info *map0 = m0;
> + const struct nfit_set_info *map1 = m1;
>  
>
>
>
>   return memcmp(&map0->region_offset, &map1->region_offset,
>   sizeof(u64));
> @@ -2310,8 +2294,8 @@ static int cmp_map_compat(const void *m0, const void *m1)
>  
>
>
>
>  static int cmp_map(const void *m0, const void *m1)
>  {
> - const struct nfit_set_info_map *map0 = m0;
> - const struct nfit_set_info_map *map1 = m1;
> + const struct nfit_set_info *map0 = m0;
> + const struct nfit_set_info *map1 = m1;
>  
>
>
>
>   if (map0->region_offset < map1->region_offset)
>   return -1;
> @@ -2322,8 +2306,8 @@ static int cmp_map(const void *m0, const void *m1)
>  
>
>
>
>  static int cmp_map2(const void *m0, const void *m1)
>  {
> - const struct nfit_set_info_map2 *map0 = m0;
> - const struct nfit_set_info_map2 *map1 = m1;
> + const struct nfit_set_info2 *map0 = m0;
> + const struct nfit_set_info2 *map1 = m1;
>  
>
>
>
>   if (map0->region_offset < map1->region_offset)
>   return -1;
> @@ -2361,22 +2345,22 @@ static int acpi_nfit_init_interleave_set(struct acpi_nfit_desc *acpi_desc,
>   return -ENOMEM;
>   import_guid(&nd_set->type_guid, spa->range_guid);
>  
>
>
>
> - info = devm_kzalloc(dev, sizeof_nfit_set_info(nr), GFP_KERNEL);
> + info = devm_kcalloc(dev, nr, sizeof(*info), GFP_KERNEL);
>   if (!info)
>   return -ENOMEM;
>  
>
>
>
> - info2 = devm_kzalloc(dev, sizeof_nfit_set_info2(nr), GFP_KERNEL);
> + info2 = devm_kcalloc(dev, nr, sizeof(*info2), GFP_KERNEL);
>   if (!info2)
>   return -ENOMEM;
>  
>
>
>
>   for (i = 0; i < nr; i++) {
>   struct nd_mapping_desc *mapping = &ndr_desc->mapping[i];
> - struct nfit_set_info_map *map = &info->mapping[i];
> - struct nfit_set_info_map2 *map2 = &info2->mapping[i];
>   struct nvdimm *nvdimm = mapping->nvdimm;
>   struct nfit_mem *nfit_mem = nvdimm_provider_data(nvdimm);
> - struct acpi_nfit_memory_map *memdev = memdev_from_spa(acpi_desc,
> - spa->range_index, i);
> + struct nfit_set_info *map = &info[i];
> + struct nfit_set_info2 *map2 = &info2[i];
> + struct acpi_nfit_memory_map *memdev =
> + memdev_from_spa(acpi_desc, spa->range_index, i);
>   struct acpi_nfit_control_region *dcr = nfit_mem->dcr;
>  
>
>
>
>   if (!memdev || !nfit_mem->dcr) {
> @@ -2395,23 +2379,20 @@ static int acpi_nfit_init_interleave_set(struct acpi_nfit_desc *acpi_desc,
>   }
>  
>
>
>
>   /* v1.1 namespaces */
> - sort(&info->mapping[0], nr, sizeof(struct nfit_set_info_map),
> - cmp_map, NULL);
> - nd_set->cookie1 = nd_fletcher64(info, sizeof_nfit_set_info(nr), 0);
> + sort(info, nr, sizeof(*info), cmp_map, NULL);
> + nd_set->cookie1 = nd_fletcher64(info, sizeof(*info) * nr, 0);
>  
>
>
>
>   /* v1.2 namespaces */
> - sort(&info2->mapping[0], nr, sizeof(struct nfit_set_info_map2),
> - cmp_map2, NULL);
> - nd_set->cookie2 = nd_fletcher64(info2, sizeof_nfit_set_info2(nr), 0);
> + sort(info2, nr, sizeof(*info2), cmp_map2, NULL);
> + nd_set->cookie2 = nd_fletcher64(info2, sizeof(*info2) * nr, 0);
>  
>
>
>
>   /* support v1.1 namespaces created with the wrong sort order */
> - sort(&info->mapping[0], nr, sizeof(struct nfit_set_info_map),
> - cmp_map_compat, NULL);
> - nd_set->altcookie = nd_fletcher64(info, sizeof_nfit_set_info(nr), 0);
> + sort(info, nr, sizeof(*info), cmp_map_compat, NULL);
> + nd_set->altcookie = nd_fletcher64(info, sizeof(*info) * nr, 0);
>  
>
>
>
>   /* record the result of the sort for the mapping position */
>   for (i = 0; i < nr; i++) {
> - struct nfit_set_info_map2 *map2 = &info2->mapping[i];
> + struct nfit_set_info2 *map2 = &info2[i];
>   int j;
>  
>
>
>
>   for (j = 0; j < nr; j++) {
> _______________________________________________
> Linux-nvdimm mailing list -- [email protected]
> To unsubscribe send an email to [email protected]

2021-01-05 23:06:59

by Dan Williams

[permalink] [raw]
Subject: Re: [PATCH] ACPI: NFIT: Fix flexible_array.cocci warnings

On Tue, Jan 5, 2021 at 1:28 PM Verma, Vishal L <[email protected]> wrote:
>
> On Tue, 2021-01-05 at 13:03 -0800, Dan Williams wrote:
> > Julia and 0day report:
> >
> > Zero-length and one-element arrays are deprecated, see
> > Documentation/process/deprecated.rst
> > Flexible-array members should be used instead.
> >
> > However, a straight conversion to flexible arrays yields:
> >
> > drivers/acpi/nfit/core.c:2276:4: error: flexible array member in a struct with no named members
> > drivers/acpi/nfit/core.c:2287:4: error: flexible array member in a struct with no named members
> >
> > Instead, just use plain arrays not embedded a flexible arrays.
>
> This reads a bit awkwardly, maybe:
>
> "Just use plain arrays instead of embedded flexible arrays."

yeah, umm, I left that extra "a" in there as a test... you passed! :)

>
> Other than that, the patch looks looks good:
> Reviewed-by: Vishal Verma <[email protected]>

Thanks.