[PATCH -next v2] checkpatch: Add check for array allocator family argument order

[PATCH -next v2] checkpatch: Add check for array allocator family argument order

[Liao Chang]

These array allocator family are sometimes misused with the first and
second arguments switchted.

Same issue with calloc, kvcalloc, kvmalloc_array etc.

Bleat if sizeof is the first argument.

Link: https://lore.kernel.org/lkml/5374345c-7973-6a3c-d559-73bf4ac15079@redhat.com/
Signed-off-by: Liao Chang <liaochang1@huawei.com>
Acked-by: Joe Perches <joe@perches.com>
---
v2:
1. Acked-by Joe Perches.
2. Use lore links in Link tag.

---
 scripts/checkpatch.pl | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 1e5e66ae5a52..a9a9dc277cff 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -7128,7 +7128,7 @@ sub process {
 		}
 
 # check for alloc argument mismatch
-		if ($line =~ /\b((?:devm_)?(?:kcalloc|kmalloc_array))\s*\(\s*sizeof\b/) {
+		if ($line =~ /\b((?:devm_)?((?:k|kv)?(calloc|malloc_array)(?:_node)?))\s*\(\s*sizeof\b/) {
 			WARN("ALLOC_ARRAY_ARGS",
 			     "$1 uses number as first arg, sizeof is generally wrong\n" . $herecurr);
 		}
-- 
2.17.1

Re: [PATCH -next v2] checkpatch: Add check for array allocator family argument order

[Lukas Bulwahn]

On Fri, Nov 4, 2022 at 8:08 AM Liao Chang <liaochang1@huawei.com> wrote:
>
> These array allocator family are sometimes misused with the first and
> second arguments switchted.

Just a nit:

s/switchted/switched/

But probably you actually mean "swapped". I think there is a slight
difference between the two words, "switched" and "swapped". And here
the arguments are swapped. Note: I am also not a native speaker.

For the implementation change:

Acked-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>

How many new findings are now identified with this extended check on
linux-next? Could you run checkpatch on all files of linux-next and
share the new findings? Then we can do a quick scan if some instances
should be immediately fixed or some janitor should follow through with
such a task.

Lukas

>
> Same issue with calloc, kvcalloc, kvmalloc_array etc.
>
> Bleat if sizeof is the first argument.
>
> Link: https://lore.kernel.org/lkml/5374345c-7973-6a3c-d559-73bf4ac15079@redhat.com/
> Signed-off-by: Liao Chang <liaochang1@huawei.com>
> Acked-by: Joe Perches <joe@perches.com>
> ---
> v2:
> 1. Acked-by Joe Perches.
> 2. Use lore links in Link tag.
>
> ---
>  scripts/checkpatch.pl | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
> index 1e5e66ae5a52..a9a9dc277cff 100755
> --- a/scripts/checkpatch.pl
> +++ b/scripts/checkpatch.pl
> @@ -7128,7 +7128,7 @@ sub process {
>                 }
>
>  # check for alloc argument mismatch
> -               if ($line =~ /\b((?:devm_)?(?:kcalloc|kmalloc_array))\s*\(\s*sizeof\b/) {
> +               if ($line =~ /\b((?:devm_)?((?:k|kv)?(calloc|malloc_array)(?:_node)?))\s*\(\s*sizeof\b/) {
>                         WARN("ALLOC_ARRAY_ARGS",
>                              "$1 uses number as first arg, sizeof is generally wrong\n" . $herecurr);
>                 }
> --
> 2.17.1
>

Re: [PATCH -next v2] checkpatch: Add check for array allocator family argument order

[Joe Perches]

On Fri, 2022-11-04 at 09:35 +0100, Lukas Bulwahn wrote:
> On Fri, Nov 4, 2022 at 8:08 AM Liao Chang <liaochang1@huawei.com> wrote:
> > 
> > These array allocator family are sometimes misused with the first and
> > second arguments switchted.
> 
> Just a nit:
> 
> s/switchted/switched/
> 
> But probably you actually mean "swapped". I think there is a slight
> difference between the two words, "switched" and "swapped". And here
> the arguments are swapped. Note: I am also not a native speaker.
> 
> For the implementation change:
> 
> Acked-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
> 
> How many new findings are now identified with this extended check on
> linux-next? Could you run checkpatch on all files of linux-next and
> share the new findings? Then we can do a quick scan if some instances
> should be immediately fixed or some janitor should follow through with
> such a task.

There are ~25.
It's fairly trivial Lukas and only cosmetic.

https://lore.kernel.org/lkml/d92ada3062bc1c3a7557bfa0499fc4a8cee3aa10.camel@perches.com/

Re: [PATCH -next v2] checkpatch: Add check for array allocator family argument order

[Christophe JAILLET]

Le 04/11/2022 à 08:05, Liao Chang a écrit :
> These array allocator family are sometimes misused with the first and
> second arguments switchted.
> 
> Same issue with calloc, kvcalloc, kvmalloc_array etc.
> 
> Bleat if sizeof is the first argument.
> 
> Link: https://lore.kernel.org/lkml/5374345c-7973-6a3c-d559-73bf4ac15079@redhat.com/
> Signed-off-by: Liao Chang <liaochang1@huawei.com>
> Acked-by: Joe Perches <joe@perches.com>
> ---
> v2:
> 1. Acked-by Joe Perches.
> 2. Use lore links in Link tag.
> 
> ---
>   scripts/checkpatch.pl | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
> index 1e5e66ae5a52..a9a9dc277cff 100755
> --- a/scripts/checkpatch.pl
> +++ b/scripts/checkpatch.pl
> @@ -7128,7 +7128,7 @@ sub process {
>   		}
>   
>   # check for alloc argument mismatch
> -		if ($line =~ /\b((?:devm_)?(?:kcalloc|kmalloc_array))\s*\(\s*sizeof\b/) {
> +		if ($line =~ /\b((?:devm_)?((?:k|kv)?(calloc|malloc_array)(?:_node)?))\s*\(\s*sizeof\b/) {
>   			WARN("ALLOC_ARRAY_ARGS",
>   			     "$1 uses number as first arg, sizeof is generally wrong\n" . $herecurr);
>   		}

Hi,

Should the devm_ and not devm_ cases be separated?

In the devm_case, sizeof will never be just after the first '('.

CJ

Re: [PATCH -next v2] checkpatch: Add check for array allocator family argument order

[Joe Perches]

On Fri, 2022-11-04 at 18:08 +0100, Christophe JAILLET wrote:
> Le 04/11/2022 à 08:05, Liao Chang a écrit :
> > These array allocator family are sometimes misused with the first and
> > second arguments switchted.
> > 
> > Same issue with calloc, kvcalloc, kvmalloc_array etc.
> > 
> > Bleat if sizeof is the first argument.
> > 
> > Link: https://lore.kernel.org/lkml/5374345c-7973-6a3c-d559-73bf4ac15079@redhat.com/
> > Signed-off-by: Liao Chang <liaochang1@huawei.com>
> > Acked-by: Joe Perches <joe@perches.com>
> > ---
> > v2:
> > 1. Acked-by Joe Perches.
> > 2. Use lore links in Link tag.
> > 
> > ---
> >   scripts/checkpatch.pl | 2 +-
> >   1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
> > index 1e5e66ae5a52..a9a9dc277cff 100755
> > --- a/scripts/checkpatch.pl
> > +++ b/scripts/checkpatch.pl
> > @@ -7128,7 +7128,7 @@ sub process {
> >   		}
> >   
> >   # check for alloc argument mismatch
> > -		if ($line =~ /\b((?:devm_)?(?:kcalloc|kmalloc_array))\s*\(\s*sizeof\b/) {
> > +		if ($line =~ /\b((?:devm_)?((?:k|kv)?(calloc|malloc_array)(?:_node)?))\s*\(\s*sizeof\b/) {
> >   			WARN("ALLOC_ARRAY_ARGS",
> >   			     "$1 uses number as first arg, sizeof is generally wrong\n" . $herecurr);
> >   		}
> 
> Hi,
> 
> Should the devm_ and not devm_ cases be separated?
> 
> In the devm_case, sizeof will never be just after the first '('.

Right.

Likely this works better:
---
 scripts/checkpatch.pl | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 7be93c3df2bcb..7f37976a9f8b5 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -7145,12 +7145,18 @@ sub process {
 			     "Reusing the krealloc arg is almost always a bug\n" . $herecurr);
 		}
 
-# check for alloc argument mismatch
-		if ($line =~ /\b((?:devm_)?(?:kcalloc|kmalloc_array))\s*\(\s*sizeof\b/) {
+# check for alloc argument mismatch in alloc functions
+		if ($line =~ /\b(((?:k|kv)?(calloc|malloc_array)(?:_node)?))\s*\(\s*sizeof\b/) {
 			WARN("ALLOC_ARRAY_ARGS",
 			     "$1 uses number as first arg, sizeof is generally wrong\n" . $herecurr);
 		}
 
+# check for alloc argument mismatch in devm_ alloc functions
+		if ($line =~ /\b(devm_((?:k|kv)?(calloc|malloc_array)(?:_node)?))\s*\(\s*$FuncArg\s*,\s*sizeof\b/) {
+			WARN("ALLOC_ARRAY_ARGS",
+			     "$1 uses number as second arg, sizeof is generally wrong\n" . $herecurr);
+		}
+
 # check for multiple semicolons
 		if ($line =~ /;\s*;\s*$/) {
 			if (WARN("ONE_SEMICOLON",

Re: [PATCH -next v2] checkpatch: Add check for array allocator family argument order

[Christophe JAILLET]

Le 05/11/2022 à 18:24, Joe Perches a écrit :
> On Fri, 2022-11-04 at 18:08 +0100, Christophe JAILLET wrote:
>> Le 04/11/2022 à 08:05, Liao Chang a écrit :
>>> These array allocator family are sometimes misused with the first and
>>> second arguments switchted.
>>>
>>> Same issue with calloc, kvcalloc, kvmalloc_array etc.
>>>
>>> Bleat if sizeof is the first argument.
>>>
>>> Link: https://lore.kernel.org/lkml/5374345c-7973-6a3c-d559-73bf4ac15079@redhat.com/
>>> Signed-off-by: Liao Chang <liaochang1@huawei.com>
>>> Acked-by: Joe Perches <joe@perches.com>
>>> ---
>>> v2:
>>> 1. Acked-by Joe Perches.
>>> 2. Use lore links in Link tag.
>>>
>>> ---
>>>    scripts/checkpatch.pl | 2 +-
>>>    1 file changed, 1 insertion(+), 1 deletion(-)
>>>
>>> diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
>>> index 1e5e66ae5a52..a9a9dc277cff 100755
>>> --- a/scripts/checkpatch.pl
>>> +++ b/scripts/checkpatch.pl
>>> @@ -7128,7 +7128,7 @@ sub process {
>>>    		}
>>>    
>>>    # check for alloc argument mismatch
>>> -		if ($line =~ /\b((?:devm_)?(?:kcalloc|kmalloc_array))\s*\(\s*sizeof\b/) {
>>> +		if ($line =~ /\b((?:devm_)?((?:k|kv)?(calloc|malloc_array)(?:_node)?))\s*\(\s*sizeof\b/) {
>>>    			WARN("ALLOC_ARRAY_ARGS",
>>>    			     "$1 uses number as first arg, sizeof is generally wrong\n" . $herecurr);
>>>    		}
>> Hi,
>>
>> Should the devm_ and not devm_ cases be separated?
>>
>> In the devm_case, sizeof will never be just after the first '('.
> Right.
>
> Likely this works better:
> ---
>   scripts/checkpatch.pl | 10 ++++++++--
>   1 file changed, 8 insertions(+), 2 deletions(-)
>
> diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
> index 7be93c3df2bcb..7f37976a9f8b5 100755
> --- a/scripts/checkpatch.pl
> +++ b/scripts/checkpatch.pl
> @@ -7145,12 +7145,18 @@ sub process {
>   			     "Reusing the krealloc arg is almost always a bug\n" . $herecurr);
>   		}
>   
> -# check for alloc argument mismatch
> -		if ($line =~ /\b((?:devm_)?(?:kcalloc|kmalloc_array))\s*\(\s*sizeof\b/) {
> +# check for alloc argument mismatch in alloc functions
> +		if ($line =~ /\b(((?:k|kv)?(calloc|malloc_array)(?:_node)?))\s*\(\s*sizeof\b/) {
>   			WARN("ALLOC_ARRAY_ARGS",
>   			     "$1 uses number as first arg, sizeof is generally wrong\n" . $herecurr);
>   		}
>   
> +# check for alloc argument mismatch in devm_ alloc functions
> +		if ($line =~ /\b(devm_((?:k|kv)?(calloc|malloc_array)(?:_node)?))\s*\(\s*$FuncArg\s*,\s*sizeof\b/) {
> +			WARN("ALLOC_ARRAY_ARGS",
> +			     "$1 uses number as second arg, sizeof is generally wrong\n" . $herecurr);
> +		}
> +
>   # check for multiple semicolons
>   		if ($line =~ /;\s*;\s*$/) {
>   			if (WARN("ONE_SEMICOLON",
>
+1

Re: [PATCH -next v2] checkpatch: Add check for array allocator family argument order

[liaochang (A)]

在 2022/11/4 16:35, Lukas Bulwahn 写道:
> On Fri, Nov 4, 2022 at 8:08 AM Liao Chang <liaochang1@huawei.com> wrote:
>>
>> These array allocator family are sometimes misused with the first and
>> second arguments switchted.
> 
> Just a nit:
> 
> s/switchted/switched/
> 
> But probably you actually mean "swapped". I think there is a slight
> difference between the two words, "switched" and "swapped". And here
> the arguments are swapped. Note: I am also not a native speaker.
> 
> For the implementation change:
> 
> Acked-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
> 
> How many new findings are now identified with this extended check on
> linux-next? Could you run checkpatch on all files of linux-next and
> share the new findings? Then we can do a quick scan if some instances
> should be immediately fixed or some janitor should follow through with
> such a task.

The scan result for v6.1-rc3:

./kernel/watch_queue.c:276:     pages = kcalloc(sizeof(struct page *), nr_pages, GFP_KERNEL);
./virt/kvm/kvm_main.c:411:              mc->objects = kvmalloc_array(sizeof(void *), capacity, gfp);
./tools/objtool/check.c:288:    struct cfi_state *cfi = calloc(sizeof(struct cfi_state), 1);
./tools/objtool/check.c:517:    file->pv_ops = calloc(sizeof(struct pv_state), nr);
./kernel/bpf/bpf_local_storage.c:623:   smap->buckets = kvcalloc(sizeof(*smap->buckets), nbuckets,
./tools/perf/builtin-record.c:4076:             rec->switch_output.filenames = calloc(sizeof(char *),
./fs/btrfs/send.c:7913: sctx->clone_roots = kvcalloc(sizeof(*sctx->clone_roots),
./drivers/scsi/bfa/bfad_bsg.c:3247:     buf_base = kcalloc(sizeof(struct bfad_buf_info) +
./sound/core/seq/seq_memory.c:379:      cellptr = kvmalloc_array(sizeof(struct snd_seq_event_cell), pool->size,
./tools/lib/bpf/libbpf.c:8220:  gen = calloc(sizeof(*gen), 1);
./tools/perf/util/metricgroup.c:269:    metric_events = calloc(sizeof(void *), ids_size + 1);
./tools/perf/util/hist.c:492:           he->res_samples = calloc(sizeof(struct res_sample),
./tools/perf/util/bpf-loader.c:574:     priv = calloc(sizeof(*priv), 1);
./tools/perf/util/synthetic-events.c:1040:      synthesize_threads = calloc(sizeof(pthread_t), thread_nr);
./tools/perf/util/synthetic-events.c:1044:      args = calloc(sizeof(*args), thread_nr);
./tools/perf/util/stat-shadow.c:390:                    metric_events = calloc(sizeof(struct evsel *),
./drivers/soc/fsl/dpio/dpio-service.c:526:      ed = kcalloc(sizeof(struct qbman_eq_desc), 32, GFP_KERNEL);
./drivers/gpu/drm/nouveau/nouveau_svm.c:1000:   buffer->fault = kvcalloc(sizeof(*buffer->fault), buffer->entries, GFP_KERNEL);
./tools/testing/selftests/memfd/fuse_test.c:257:        zero = calloc(sizeof(*zero), mfd_def_size);
./tools/testing/selftests/bpf/test_progs.c:1324:        dispatcher_threads = calloc(sizeof(pthread_t), env.workers);
./tools/testing/selftests/bpf/test_progs.c:1325:        data = calloc(sizeof(struct dispatch_data), env.workers);
./tools/testing/selftests/bpf/test_progs.c:1327:        env.worker_current_test = calloc(sizeof(int), env.workers);
./tools/testing/selftests/bpf/test_progs.c:1642:                env.worker_pids = calloc(sizeof(__pid_t), env.workers);
./tools/testing/selftests/bpf/test_progs.c:1643:                env.worker_socks = calloc(sizeof(int), env.workers);
./tools/testing/selftests/arm64/fp/fp-stress.c:458:     children = calloc(sizeof(*children), tests);
./tools/testing/selftests/bpf/prog_tests/fexit_bpf2bpf.c:87:    link = calloc(sizeof(struct bpf_link *), prog_cnt);
./tools/testing/selftests/bpf/prog_tests/fexit_bpf2bpf.c:91:    prog = calloc(sizeof(struct bpf_program *), prog_cnt);

> 
> Lukas
> 
>>
>> Same issue with calloc, kvcalloc, kvmalloc_array etc.
>>
>> Bleat if sizeof is the first argument.
>>
>> Link: https://lore.kernel.org/lkml/5374345c-7973-6a3c-d559-73bf4ac15079@redhat.com/
>> Signed-off-by: Liao Chang <liaochang1@huawei.com>
>> Acked-by: Joe Perches <joe@perches.com>
>> ---
>> v2:
>> 1. Acked-by Joe Perches.
>> 2. Use lore links in Link tag.
>>
>> ---
>>  scripts/checkpatch.pl | 2 +-
>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
>> index 1e5e66ae5a52..a9a9dc277cff 100755
>> --- a/scripts/checkpatch.pl
>> +++ b/scripts/checkpatch.pl
>> @@ -7128,7 +7128,7 @@ sub process {
>>                 }
>>
>>  # check for alloc argument mismatch
>> -               if ($line =~ /\b((?:devm_)?(?:kcalloc|kmalloc_array))\s*\(\s*sizeof\b/) {
>> +               if ($line =~ /\b((?:devm_)?((?:k|kv)?(calloc|malloc_array)(?:_node)?))\s*\(\s*sizeof\b/) {
>>                         WARN("ALLOC_ARRAY_ARGS",
>>                              "$1 uses number as first arg, sizeof is generally wrong\n" . $herecurr);
>>                 }
>> --
>> 2.17.1
>>
> .

-- 
BR,
Liao, Chang

Re: [PATCH -next v2] checkpatch: Add check for array allocator family argument order

[liaochang (A)]

在 2022/11/6 5:36, Christophe JAILLET 写道:
> 
> Le 05/11/2022 à 18:24, Joe Perches a écrit :
>> On Fri, 2022-11-04 at 18:08 +0100, Christophe JAILLET wrote:
>>> Le 04/11/2022 à 08:05, Liao Chang a écrit :
>>>> These array allocator family are sometimes misused with the first and
>>>> second arguments switchted.
>>>>
>>>> Same issue with calloc, kvcalloc, kvmalloc_array etc.
>>>>
>>>> Bleat if sizeof is the first argument.
>>>>
>>>> Link: https://lore.kernel.org/lkml/5374345c-7973-6a3c-d559-73bf4ac15079@redhat.com/
>>>> Signed-off-by: Liao Chang <liaochang1@huawei.com>
>>>> Acked-by: Joe Perches <joe@perches.com>
>>>> ---
>>>> v2:
>>>> 1. Acked-by Joe Perches.
>>>> 2. Use lore links in Link tag.
>>>>
>>>> ---
>>>>    scripts/checkpatch.pl | 2 +-
>>>>    1 file changed, 1 insertion(+), 1 deletion(-)
>>>>
>>>> diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
>>>> index 1e5e66ae5a52..a9a9dc277cff 100755
>>>> --- a/scripts/checkpatch.pl
>>>> +++ b/scripts/checkpatch.pl
>>>> @@ -7128,7 +7128,7 @@ sub process {
>>>>            }
>>>>       # check for alloc argument mismatch
>>>> -        if ($line =~ /\b((?:devm_)?(?:kcalloc|kmalloc_array))\s*\(\s*sizeof\b/) {
>>>> +        if ($line =~ /\b((?:devm_)?((?:k|kv)?(calloc|malloc_array)(?:_node)?))\s*\(\s*sizeof\b/) {
>>>>                WARN("ALLOC_ARRAY_ARGS",
>>>>                     "$1 uses number as first arg, sizeof is generally wrong\n" . $herecurr);
>>>>            }
>>> Hi,
>>>
>>> Should the devm_ and not devm_ cases be separated?
>>>
>>> In the devm_case, sizeof will never be just after the first '('.
>> Right.
>>
>> Likely this works better:
>> ---
>>   scripts/checkpatch.pl | 10 ++++++++--
>>   1 file changed, 8 insertions(+), 2 deletions(-)
>>
>> diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
>> index 7be93c3df2bcb..7f37976a9f8b5 100755
>> --- a/scripts/checkpatch.pl
>> +++ b/scripts/checkpatch.pl
>> @@ -7145,12 +7145,18 @@ sub process {
>>                    "Reusing the krealloc arg is almost always a bug\n" . $herecurr);
>>           }
>>   -# check for alloc argument mismatch
>> -        if ($line =~ /\b((?:devm_)?(?:kcalloc|kmalloc_array))\s*\(\s*sizeof\b/) {
>> +# check for alloc argument mismatch in alloc functions
>> +        if ($line =~ /\b(((?:k|kv)?(calloc|malloc_array)(?:_node)?))\s*\(\s*sizeof\b/) {
>>               WARN("ALLOC_ARRAY_ARGS",
>>                    "$1 uses number as first arg, sizeof is generally wrong\n" . $herecurr);
>>           }
>>   +# check for alloc argument mismatch in devm_ alloc functions
>> +        if ($line =~ /\b(devm_((?:k|kv)?(calloc|malloc_array)(?:_node)?))\s*\(\s*$FuncArg\s*,\s*sizeof\b/) {
>> +            WARN("ALLOC_ARRAY_ARGS",
>> +                 "$1 uses number as second arg, sizeof is generally wrong\n" . $herecurr);
>> +        }
>> +
>>   # check for multiple semicolons
>>           if ($line =~ /;\s*;\s*$/) {
>>               if (WARN("ONE_SEMICOLON",
>>
> +1
> 
+1, thanks.

BTW, i find the v2 has been added to the -mm mm-nonmm-unstable branch,
do i need to submit new version includes above change?

> 
> .

-- 
BR,
Liao, Chang