[PATCH] docs: kernel-doc: python: strip __counted_by_ptr macro

[PATCH] docs: kernel-doc: python: strip __counted_by_ptr macro

[Tudor Ambarus]

The `__counted_by_ptr` macro was recently introduced [1] to extend
bounds checking semantics to standard dynamically allocated pointers.

However, the new Python implementation of kernel-doc does not currently
recognize it as a compiler attribute. When kernel-doc encounters a
struct member annotated with this macro, it fails to parse the variable
name correctly, resulting in false-positive warnings like:

  Warning: ... struct member '__counted_by_ptr(cmdcnt' not described

Add `__counted_by_ptr` to the `struct_xforms` regex list so it gets
safely stripped out during the parsing phase, mirroring the existing
behavior for `__counted_by`. Update the corresponding unit tests.

Link: https://git.kernel.org/torvalds/c/150a04d817d8 [1]
Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
---
 tools/lib/python/kdoc/xforms_lists.py | 1 +
 tools/unittests/test_cmatch.py        | 1 +
 2 files changed, 2 insertions(+)

diff --git a/tools/lib/python/kdoc/xforms_lists.py b/tools/lib/python/kdoc/xforms_lists.py
index f6ea9efb11ae..118156ea8cd2 100644
--- a/tools/lib/python/kdoc/xforms_lists.py
+++ b/tools/lib/python/kdoc/xforms_lists.py
@@ -29,6 +29,7 @@ class CTransforms:
         (CMatch("__aligned"), ""),
         (CMatch("__counted_by"), ""),
         (CMatch("__counted_by_(le|be)"), ""),
+        (CMatch("__counted_by_ptr"), ""),
         (CMatch("__guarded_by"), ""),
         (CMatch("__pt_guarded_by"), ""),
         (CMatch("__packed"), ""),
diff --git a/tools/unittests/test_cmatch.py b/tools/unittests/test_cmatch.py
index 7b996f83784d..109141cd2ab8 100755
--- a/tools/unittests/test_cmatch.py
+++ b/tools/unittests/test_cmatch.py
@@ -320,6 +320,7 @@ class TestSubWithLocalXforms(TestCaseDiff):
         (CMatch('__aligned'), ' '),
         (CMatch('__counted_by'), ' '),
         (CMatch('__counted_by_(le|be)'), ' '),
+        (CMatch('__counted_by_ptr'), ' '),
         (CMatch('__guarded_by'), ' '),
         (CMatch('__pt_guarded_by'), ' '),
 

---
base-commit: 254f49634ee16a731174d2ae34bc50bd5f45e731
change-id: 20260506-kdoc-__counted_by_ptr-1e206f3f1dc1

Best regards,
-- 
Tudor Ambarus <tudor.ambarus@linaro.org>

Re: [PATCH] docs: kernel-doc: python: strip __counted_by_ptr macro

[Randy Dunlap]

On 5/6/26 4:04 AM, Tudor Ambarus wrote:
> The `__counted_by_ptr` macro was recently introduced [1] to extend
> bounds checking semantics to standard dynamically allocated pointers.
> 
> However, the new Python implementation of kernel-doc does not currently
> recognize it as a compiler attribute. When kernel-doc encounters a
> struct member annotated with this macro, it fails to parse the variable
> name correctly, resulting in false-positive warnings like:
> 
>   Warning: ... struct member '__counted_by_ptr(cmdcnt' not described
> 
> Add `__counted_by_ptr` to the `struct_xforms` regex list so it gets
> safely stripped out during the parsing phase, mirroring the existing
> behavior for `__counted_by`. Update the corresponding unit tests.
> 
> Link: https://git.kernel.org/torvalds/c/150a04d817d8 [1]
> Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>

Acked-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Thanks.

> ---
>  tools/lib/python/kdoc/xforms_lists.py | 1 +
>  tools/unittests/test_cmatch.py        | 1 +
>  2 files changed, 2 insertions(+)
> 
> diff --git a/tools/lib/python/kdoc/xforms_lists.py b/tools/lib/python/kdoc/xforms_lists.py
> index f6ea9efb11ae..118156ea8cd2 100644
> --- a/tools/lib/python/kdoc/xforms_lists.py
> +++ b/tools/lib/python/kdoc/xforms_lists.py
> @@ -29,6 +29,7 @@ class CTransforms:
>          (CMatch("__aligned"), ""),
>          (CMatch("__counted_by"), ""),
>          (CMatch("__counted_by_(le|be)"), ""),
> +        (CMatch("__counted_by_ptr"), ""),
>          (CMatch("__guarded_by"), ""),
>          (CMatch("__pt_guarded_by"), ""),
>          (CMatch("__packed"), ""),
> diff --git a/tools/unittests/test_cmatch.py b/tools/unittests/test_cmatch.py
> index 7b996f83784d..109141cd2ab8 100755
> --- a/tools/unittests/test_cmatch.py
> +++ b/tools/unittests/test_cmatch.py
> @@ -320,6 +320,7 @@ class TestSubWithLocalXforms(TestCaseDiff):
>          (CMatch('__aligned'), ' '),
>          (CMatch('__counted_by'), ' '),
>          (CMatch('__counted_by_(le|be)'), ' '),
> +        (CMatch('__counted_by_ptr'), ' '),
>          (CMatch('__guarded_by'), ' '),
>          (CMatch('__pt_guarded_by'), ' '),
>  
> 
> ---
> base-commit: 254f49634ee16a731174d2ae34bc50bd5f45e731
> change-id: 20260506-kdoc-__counted_by_ptr-1e206f3f1dc1
> 
> Best regards,

-- 
~Randy

Re: [PATCH] docs: kernel-doc: python: strip __counted_by_ptr macro

[Kees Cook]

On Wed, May 06, 2026 at 11:04:12AM +0000, Tudor Ambarus wrote:
> The `__counted_by_ptr` macro was recently introduced [1] to extend
> bounds checking semantics to standard dynamically allocated pointers.
> 
> However, the new Python implementation of kernel-doc does not currently
> recognize it as a compiler attribute. When kernel-doc encounters a
> struct member annotated with this macro, it fails to parse the variable
> name correctly, resulting in false-positive warnings like:
> 
>   Warning: ... struct member '__counted_by_ptr(cmdcnt' not described
> 
> Add `__counted_by_ptr` to the `struct_xforms` regex list so it gets
> safely stripped out during the parsing phase, mirroring the existing
> behavior for `__counted_by`. Update the corresponding unit tests.
> 
> Link: https://git.kernel.org/torvalds/c/150a04d817d8 [1]
> Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>

Reviewed-by: Kees Cook <kees@kernel.org>

-- 
Kees Cook