2022-03-25 18:47:27

by baihaowen

Subject: [PATCH] selftests/bpf: Fix warning comparing pointer to 0

Avoid pointer type value compared with 0 to make code clear.

Signed-off-by: Haowen Bai <[email protected]>
---
tools/testing/selftests/bpf/progs/map_ptr_kern.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/bpf/progs/map_ptr_kern.c b/tools/testing/selftests/bpf/progs/map_ptr_kern.c
index b64df94..db388f5 100644
--- a/tools/testing/selftests/bpf/progs/map_ptr_kern.c
+++ b/tools/testing/selftests/bpf/progs/map_ptr_kern.c
@@ -367,7 +367,7 @@ static inline int check_array_of_maps(void)

VERIFY(check_default(&array_of_maps->map, map));
inner_map = bpf_map_lookup_elem(array_of_maps, &key);
- VERIFY(inner_map != 0);
+ VERIFY(inner_map != NULL);
VERIFY(inner_map->map.max_entries == INNER_MAX_ENTRIES);

return 1;
@@ -394,7 +394,7 @@ static inline int check_hash_of_maps(void)

VERIFY(check_default(&hash_of_maps->map, map));
inner_map = bpf_map_lookup_elem(hash_of_maps, &key);
- VERIFY(inner_map != 0);
+ VERIFY(inner_map != NULL);
VERIFY(inner_map->map.max_entries == INNER_MAX_ENTRIES);

return 1;
--
2.7.4

2022-03-25 20:39:25

by Shuah Khan

Subject: Re: [PATCH] selftests/bpf: Fix warning comparing pointer to 0

On 3/23/22 8:08 PM, Haowen Bai wrote:
> Avoid pointer type value compared with 0 to make code clear.
>

Patch looks good to me. Please include the error/warn message
in the commit log. This gives reviewers information on how
this problem is found.

> Signed-off-by: Haowen Bai <[email protected]>
> ---
> tools/testing/selftests/bpf/progs/map_ptr_kern.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/tools/testing/selftests/bpf/progs/map_ptr_kern.c b/tools/testing/selftests/bpf/progs/map_ptr_kern.c
> index b64df94..db388f5 100644
> --- a/tools/testing/selftests/bpf/progs/map_ptr_kern.c
> +++ b/tools/testing/selftests/bpf/progs/map_ptr_kern.c
> @@ -367,7 +367,7 @@ static inline int check_array_of_maps(void)
>
> VERIFY(check_default(&array_of_maps->map, map));
> inner_map = bpf_map_lookup_elem(array_of_maps, &key);
> - VERIFY(inner_map != 0);
> + VERIFY(inner_map != NULL);
> VERIFY(inner_map->map.max_entries == INNER_MAX_ENTRIES);
>
> return 1;
> @@ -394,7 +394,7 @@ static inline int check_hash_of_maps(void)
>
> VERIFY(check_default(&hash_of_maps->map, map));
> inner_map = bpf_map_lookup_elem(hash_of_maps, &key);
> - VERIFY(inner_map != 0);
> + VERIFY(inner_map != NULL);
> VERIFY(inner_map->map.max_entries == INNER_MAX_ENTRIES);
>
> return 1;
>

With the change to commit log including the error/warn message and
details on how the problems is found:

Reviewed-by: Shuah Khan <[email protected]>

thanks,
-- Shuah

2022-03-31 04:26:28

by baihaowen

Subject: [PATCH V2] selftests/bpf: Fix warning comparing pointer to 0

Avoid pointer type value compared with 0 to make code clear.

reported by coccicheck:
tools/testing/selftests/bpf/progs/map_ptr_kern.c:370:21-22:
WARNING comparing pointer to 0
tools/testing/selftests/bpf/progs/map_ptr_kern.c:397:21-22:
WARNING comparing pointer to 0

Signed-off-by: Haowen Bai <[email protected]>
---
V1->V2: include the error/warn message.

tools/testing/selftests/bpf/progs/map_ptr_kern.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/bpf/progs/map_ptr_kern.c b/tools/testing/selftests/bpf/progs/map_ptr_kern.c
index b64df94..db388f5 100644
--- a/tools/testing/selftests/bpf/progs/map_ptr_kern.c
+++ b/tools/testing/selftests/bpf/progs/map_ptr_kern.c
@@ -367,7 +367,7 @@ static inline int check_array_of_maps(void)

VERIFY(check_default(&array_of_maps->map, map));
inner_map = bpf_map_lookup_elem(array_of_maps, &key);
- VERIFY(inner_map != 0);
+ VERIFY(inner_map != NULL);
VERIFY(inner_map->map.max_entries == INNER_MAX_ENTRIES);

return 1;
@@ -394,7 +394,7 @@ static inline int check_hash_of_maps(void)

VERIFY(check_default(&hash_of_maps->map, map));
inner_map = bpf_map_lookup_elem(hash_of_maps, &key);
- VERIFY(inner_map != 0);
+ VERIFY(inner_map != NULL);
VERIFY(inner_map->map.max_entries == INNER_MAX_ENTRIES);

return 1;
--
2.7.4