[PATCH v4 0/3] checkpatch: userspace improvements

[PATCH v4 0/3] checkpatch: userspace improvements

[Petr Vorel]

Changes v3->v4:
* Change test for directory to be more more generic (Joe)
* Allow to use --no-userspace (sashiko)

Link to v3:
https://lore.kernel.org/lkml/20260520100829.93791-1-pvorel@suse.cz/
https://sashiko.dev/#/patchset/20260520100829.93791-1-pvorel%40suse.cz

Petr Vorel (3):
  checkpatch: Add more userspace directories to is_userspace()
  checkpatch: Ignore <inttypes.h> format macros for userspace tools
  checkpatch: Add new option to force userspace

 scripts/checkpatch.pl | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

-- 
2.55.0

[PATCH v4 1/3] checkpatch: Add more userspace directories to is_userspace()

[Petr Vorel]

arch/ directory contains subdirectories with userspace tools (at least
arch/*/tools/ and arch/*/boot/tools/). Add check to consider any
arch/.*/tools/ subdirectory as userspace tools directory.

This helps not only to strscpy() checks but also to CamelCase checks in
the next commit to be more precise.

Follow-up: 99b70ece33d8 ("checkpatch: suppress strscpy warnings for userspace tools")
Signed-off-by: Petr Vorel <pvorel@suse.cz>
---
Changes v3->v4:
* Change test for directory to be more more generic (Joe)

 scripts/checkpatch.pl | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 4f7325fd5825..1c6ef46bae1e 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -2665,7 +2665,9 @@ sub exclude_global_initialisers {
 
 sub is_userspace {
     my ($realfile) = @_;
-    return ($realfile =~ m@^tools/@ || $realfile =~ m@^scripts/@);
+    return ($realfile =~ m@^tools/@ ||
+		$realfile =~ m@^scripts/@ ||
+		$realfile =~ m@^arch/.*\btools\b@);
 }
 
 sub process {
-- 
2.55.0

[PATCH v4 2/3] checkpatch: Ignore <inttypes.h> format macros for userspace tools

[Petr Vorel]

Constants from <inttypes.h> are used only in userspace tools, they are
from ISO C99, let's don't report it:

    arch/mips/boot/tools/relocs.c:572: CHECK: Avoid CamelCase: <PRIx32>
    arch/s390/tools/relocs.c:52: CHECK: Avoid CamelCase: <PRIu64>
    tools/testing/selftests/mm/vm_util.c:244: CHECK: Avoid CamelCase: <SCNu64>

Signed-off-by: Petr Vorel <pvorel@suse.cz>
---
The same as in v3.

 scripts/checkpatch.pl | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 1c6ef46bae1e..ff99265056f8 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -5947,6 +5947,8 @@ sub process {
 #Ignore SI style variants like nS, mV and dB
 #(ie: max_uV, regulator_min_uA_show, RANGE_mA_VALUE)
 			    $var !~ /^(?:[a-z0-9_]*|[A-Z0-9_]*)?_?[a-z][A-Z](?:_[a-z0-9_]+|_[A-Z0-9_]+)?$/ &&
+#Ignore <inttypes.h> format macros (e.g. PRIu64, SCNu64)
+			    (is_userspace($realfile) ? $var !~ /^(?:PRI|SCN)[dioux][A-Z0-9]+$/ : 1) &&
 #Ignore some three character SI units explicitly, like MiB and KHz
 			    $var !~ /^(?:[a-z_]*?)_?(?:[KMGT]iB|[KMGT]?Hz)(?:_[a-z_]+)?$/) {
 				while ($var =~ m{\b($Ident)}g) {
-- 
2.55.0

[PATCH v4 3/3] checkpatch: Add new option to force userspace

[Petr Vorel]

Also allow to use --no-userspace for userspace projects which vendored
checkpatch.pl and use --userspace globally to be able switch it off for
some files.

Signed-off-by: Petr Vorel <pvorel@suse.cz>
---
Changes v3->v4:
* Allow to use --no-userspace (sashiko)

 scripts/checkpatch.pl | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index ff99265056f8..4b6250f6a614 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -63,6 +63,7 @@ my $env_config_dir = 'CHECKPATCH_CONFIG_DIR';
 my $max_line_length = 100;
 my $ignore_perl_version = 0;
 my $spdx_cxx_comments = 0;
+my $userspace = 0;
 my $minimum_perl_version = 5.10.0;
 my $min_conf_desc_length = 4;
 my $spelling_file = "$D/spelling.txt";
@@ -143,6 +144,7 @@ Options:
                              (required by old toolchains), allow also C++
                              comments (//).
                              NOTE: it should *not* be used for Linux mainline.
+  --userspace                Force rules specific for userspace.
   --codespell                Use the codespell dictionary for spelling/typos
                              (default:$codespellfile)
   --codespellfile            Use this codespell dictionary
@@ -358,6 +360,7 @@ GetOptions(
 	'codespell!'	=> \$codespell,
 	'codespellfile=s'	=> \$user_codespellfile,
 	'typedefsfile=s'	=> \$typedefsfile,
+	'userspace!'	=> \$userspace,
 	'color=s'	=> \$color,
 	'no-color'	=> \$color,	#keep old behaviors of -nocolor
 	'nocolor'	=> \$color,	#keep old behaviors of -nocolor
@@ -2665,7 +2668,8 @@ sub exclude_global_initialisers {
 
 sub is_userspace {
     my ($realfile) = @_;
-    return ($realfile =~ m@^tools/@ ||
+    return ($userspace ||
+		$realfile =~ m@^tools/@ ||
 		$realfile =~ m@^scripts/@ ||
 		$realfile =~ m@^arch/.*\btools\b@);
 }
-- 
2.55.0

Re: [PATCH v4 0/3] checkpatch: userspace improvements

[Andrew Morton]

On Mon, 10 Aug 2026 18:45:49 +0200 Petr Vorel <pvorel@suse.cz> wrote:

> Changes v3->v4:
> * Change test for directory to be more more generic (Joe)
> * Allow to use --no-userspace (sashiko)

Sashiko had a few more questions?
	https://sashiko.dev/#/patchset/20260810164552.1049483-1-pvorel@suse.cz

Re: [PATCH v4 0/3] checkpatch: userspace improvements

[Petr Vorel]

Hi Andrew,

> On Mon, 10 Aug 2026 18:45:49 +0200 Petr Vorel <pvorel@suse.cz> wrote:

> > Changes v3->v4:
> > * Change test for directory to be more more generic (Joe)
> > * Allow to use --no-userspace (sashiko)

> Sashiko had a few more questions?
> 	https://sashiko.dev/#/patchset/20260810164552.1049483-1-pvorel@suse.cz

Thanks for a reminder. All are about kernel code being wrongly considered as user space.
At the beginning I was not sure if we need --no-userspace at all, but we
probably do for non-kernel projects which pass --userspace permanently via
configuration file.

1) The original regex was suggested by Joe and should mostly work, but using /
is indeed safer.
-m@^arch/.*\btools\b@
+m@^arch/.*/tools/@

2) my $userspace = 0 will indeed prevent --no-userspace from working as an
override. I did not considered this as important, but let's fix that.

3) return ($userspace || path based detection: dtto

=> v5

Kind regards,
Petr