If function-like macros do not utilize a parameter, it might result in a
build warning.  In our coding style guidelines, we advocate for utilizing
static inline functions to replace such macros.  This patch verifies
compliance with the new rule.

For a macro such as the one below,

 #define test(a) do { } while (0)

The test result is as follows.

 WARNING: Argument 'a' is not used in function-like macro
 #21: FILE: mm/init-mm.c:20:
 +#define test(a) do { } while (0)

 total: 0 errors, 1 warnings, 8 lines checked

Link: https://lkml.kernel.org/r/20240507032757.146386-3-21cnbao@gmail.com


Signed-off-by: Xining Xu <mac.xxn@outlook.com>
Tested-by: Barry Song <v-songbaohua@oppo.com>
Signed-off-by: Barry Song <v-songbaohua@oppo.com>
Acked-by: Joe Perches <joe@perches.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: Huacai Chen <chenhuacai@loongson.cn>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Mark Brown <broonie@kernel.org>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Dwaipayan Ray <dwaipayanray1@gmail.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Jeff Johnson <quic_jjohnson@quicinc.com>
Cc: Charlemagne Lasse <charlemagnelasse@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Checkpatch presumes attributes marked with __aligned(alignment) are part
of a function declaration and throws a warning stating that those
compiler attributes should have an identifier name which is not correct.
Add __aligned compiler attributes to the list of attribute notes
so they don't cause warnings anymore.

Signed-off-by: Marcelo Schmitt <marcelo.schmitt@analog.com>
Acked-by: Joe Perches <joe@perches.com>
Link: https://lore.kernel.org/r/1c5c93ecbd8c46a338b22a4ef52e51648e333c01.1702746240.git.marcelo.schmitt1@gmail.com


Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

ALLOW_ERROR_INJECTION macro (just like EXPORT_SYMBOL) can immediately
follow a function it annotates.

Link: https://lkml.kernel.org/r/20231109075147.2779461-1-senozhatsky@chromium.org


Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Acked-by: Joe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@canonical.com> (maintainer:CHECKPATCH)
Cc: Dwaipayan Ray <dwaipayanray1@gmail.com> (reviewer:CHECKPATCH)
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Add some warnings for using ethtool_sprintf() where a simple
ethtool_puts() would suffice.

The two cases are:

1) Use ethtool_sprintf() with just two arguments:
|       ethtool_sprintf(&data, driver[i].name);
or
2) Use ethtool_sprintf() with a standalone "%s" fmt string:
|       ethtool_sprintf(&data, "%s", driver[i].name);

The former may cause -Wformat-security warnings while the latter is just
not preferred. Both are safely in the category of warnings, not errors.

Signed-off-by: Justin Stitt <justinstitt@google.com>
Reviewed-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The definition for single-argument kfree_rcu() has been removed,
so that any further attempt to use it will result in a build error.
Because of this build error, there is no longer any need for a special
check in checkpatch.pl.

Therefore, revert commit 1eacac32.

Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>

Reword the warning to complain about line length 1st, since thats
whats actually tested.

Link: https://lkml.kernel.org/r/20230808033019.21911-3-jim.cromie@gmail.com


Cc: apw@canonical.com
Cc: joe@perches.com
Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

"externs should be avoided in .c files" needs an exception for linker
symbols, like those that mark the start, stop of many kernel sections.

Since checkpatch already checks REALNAME to avoid looking at fragments
changing vmlinux.lds.h, add a new else-if block to look at them
instead.  As a simple heuristic, treat all words (in the patch-line)
as possible symbols, to screen later warnings.

For my test case, the possible-symbols included BOUNDED_BY (a macro),
which is extra, but not troublesome - these are just to screen
WARNINGS that might be issued on later fragments (changing .c files)

Where the WARN is issued, precede it with an else-if block to catch
one common extern-in-c use case: "extern struct foo bar[]".  Here we
can at least issue a softer warning, after checking for a match with a
maybe-linker-symbol parsed earlier from the patch.

Though heuristic, it worked for my test-case, allowing both start__,
stop__ $symbol's (wo the prefixes specifically named).  I've coded it
narrowly, it can be expanded later to cover any other expressions.

It does require that the externs in .c's have the additions to
vmlinux.lds.h in the same patch.  And requires vmlinux.lds.h before .c
fragments.

Link: https://lkml.kernel.org/r/20230808033019.21911-2-jim.cromie@gmail.com


Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

RCU Tasks Trace is quite specialized, having been created specifically
for sleepable BPF programs.  Because it allows general blocking within
readers, any new use of RCU Tasks Trace must take current use cases into
account.  Therefore, update checkpatch.pl to complain about use of any of
the RCU Tasks Trace API members outside of BPF and outside of RCU itself.

[ paulmck: Apply Joe Perches feedback. ]

Cc: Andy Whitcroft <apw@canonical.com> (maintainer:CHECKPATCH)
Cc: Joe Perches <joe@perches.com> (maintainer:CHECKPATCH)
Cc: Dwaipayan Ray <dwaipayanray1@gmail.com> (reviewer:CHECKPATCH)
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: <bpf@vger.kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

Use __attribute__((__cleanup__(func))) to build:

 - simple auto-release pointers using __free()

 - 'classes' with constructor and destructor semantics for
   scope-based resource management.

 - lock guards based on the above classes.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20230612093537.614161713%40infradead.org

Fake flexible arrays have been deprecated since last millennium.  Proper
C99 flexible arrays must be used throughout the kernel so
CONFIG_FORTIFY_SOURCE and CONFIG_UBSAN_BOUNDS can provide proper array
bounds checking.

[joe@perches.com: various suggestions]
Link: https://lkml.kernel.org/r/20230601160746.up.948-kees@kernel.org
Link: https://lore.kernel.org/r/20230517204530.never.151-kees@kernel.org


Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Acked-by: Joe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Dwaipayan Ray <dwaipayanray1@gmail.com>
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Fake flexible arrays have been deprecated since last millennium. Proper
C99 flexible arrays must be used throughout the kernel so
CONFIG_FORTIFY_SOURCE and CONFIG_UBSAN_BOUNDS can provide proper array
bounds checking.

Cc: Andy Whitcroft <apw@canonical.com>
Cc: Dwaipayan Ray <dwaipayanray1@gmail.com>
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Fixed-by: Joe Perches <joe@perches.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Acked-by: Joe Perches <joe@perches.com>
Link: https://lore.kernel.org/r/20230517204530.never.151-kees@kernel.org

Warn about strcpy(), strncpy(), and strlcpy(). Suggest strscpy() and
include pointers to the open KSPP issues for each, which has further
details and replacement procedures.

Cc: Andy Whitcroft <apw@canonical.com>
Cc: Joe Perches <joe@perches.com>
Cc: Dwaipayan Ray <dwaipayanray1@gmail.com>
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20230517201349.never.582-kees@kernel.org

All headers from 'include/dt-bindings/' must be verified by checkpatch
together with Documentation bindings, because all of them are part of the
whole DT bindings system.

The requirement is dual licensed and matching patterns:
* Schemas:
    /GPL-2\.0(?:-only)? OR BSD-2-Clause/
* Headers:
    /GPL-2\.0(?:-only)? OR \S+/

Above patterns suggested by Rob at:
https://lore.kernel.org/all/CAL_Jsq+-YJsBO+LuPJ=ZQ=eb-monrwzuCppvReH+af7hYZzNaQ@mail.gmail.com

The issue was found during patch review:
https://lore.kernel.org/all/20230313201259.19998-4-ddrokosov@sberdevices.ru/

Link: https://lkml.kernel.org/r/20230404191715.7319-1-ddrokosov@sberdevices.ru


Signed-off-by: Dmitry Rokosov <ddrokosov@sberdevices.ru>
Reviewed-by: Rob Herring <robh@kernel.org>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Dwaipayan Ray <dwaipayanray1@gmail.com>
Cc: Joe Perches <joe@perches.com>
Cc: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

"Link:" and "Closes:" tags have to be used with public URLs.

It is difficult to make sure the link is public but at least we can verify
the tag is followed by 'http(s)://'.

With that, we avoid such a tag that is not allowed [1]:

  Closes: <number>

Now that we check the "link" tags are followed by a URL, we can relax the
check linked to "Reported-by being followed by a link tag" to only verify
if a "link" tag is present after the "Reported-by" one.

Link: https://lore.kernel.org/linux-doc/CAHk-=wh0v1EeDV3v8TzK81nDC40=XuTdY2MCr0xy3m3FiBV3+Q@mail.gmail.com/ [1]
Link: https://lkml.kernel.org/r/20230314-doc-checkpatch-closes-tag-v4-5-d26d1fa66f9f@tessares.net


Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Acked-by: Joe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Bagas Sanjaya <bagasdotme@gmail.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: David Airlie <airlied@gmail.com>
Cc: Dwaipayan Ray <dwaipayanray1@gmail.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kai Wasserbäch <kai@dev.carbon-project.org>
Cc: Konstantin Ryabitsev <konstantin@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Cc: Thorsten Leemhuis <linux@leemhuis.info>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

As a follow-up of a previous patch modifying the documentation to allow
using the "Closes:" tag, checkpatch.pl is updated accordingly.

checkpatch.pl now no longer complain when the "Closes:" tag is used by
itself:

  commit 76f381bb ("checkpatch: warn when unknown tags are used for links")

... or after the "Reported-by:" tag:

  commit d7f1d71e ("checkpatch: warn when Reported-by: is not followed by Link:")

Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/373
Link: https://lkml.kernel.org/r/20230314-doc-checkpatch-closes-tag-v4-4-d26d1fa66f9f@tessares.net


Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Acked-by: Joe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Bagas Sanjaya <bagasdotme@gmail.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: David Airlie <airlied@gmail.com>
Cc: Dwaipayan Ray <dwaipayanray1@gmail.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kai Wasserbäch <kai@dev.carbon-project.org>
Cc: Konstantin Ryabitsev <konstantin@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Cc: Thorsten Leemhuis <linux@leemhuis.info>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

The following commit will allow the use of a similar "link" tag.

Because there is a possibility that other similar tags will be added in
the future and to reduce the number of places where the code will be
modified to allow this new tag, a list with all these "link" tags is now
used.

Two variables are created from it: one to search for such tags and one to
print all tags in a warning message.

Link: https://lkml.kernel.org/r/20230314-doc-checkpatch-closes-tag-v4-3-d26d1fa66f9f@tessares.net


Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Suggested-by: Joe Perches <joe@perches.com>
Acked-by: Joe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Bagas Sanjaya <bagasdotme@gmail.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: David Airlie <airlied@gmail.com>
Cc: Dwaipayan Ray <dwaipayanray1@gmail.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kai Wasserbäch <kai@dev.carbon-project.org>
Cc: Konstantin Ryabitsev <konstantin@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Cc: Thorsten Leemhuis <linux@leemhuis.info>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

When checking if "Reported-by" tag is followed by "Link:", there is no
need to print the next line if there is no next line.

While at it, also mention in this case that the "Link:" tag should be
followed by a URL, similar to the next warning.

By doing that, the code is now similar to what is done above when checking
if the Co-developed-by tag is properly used.

Link: https://lkml.kernel.org/r/20230314-doc-checkpatch-closes-tag-v4-2-d26d1fa66f9f@tessares.net


Fixes: d7f1d71e ("checkpatch: warn when Reported-by: is not followed by Link:")
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Acked-by: Joe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Bagas Sanjaya <bagasdotme@gmail.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: David Airlie <airlied@gmail.com>
Cc: Dwaipayan Ray <dwaipayanray1@gmail.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kai Wasserbäch <kai@dev.carbon-project.org>
Cc: Konstantin Ryabitsev <konstantin@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Cc: Thorsten Leemhuis <linux@leemhuis.info>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Since commit 4104a206 ("checkpatch: ignore generated CamelCase defines
and enum values") enum values like ETHTOOL_LINK_MODE_Asym_Pause_BIT are
ignored.  But there are other enums like
ETHTOOL_LINK_MODE_1000baseT_Full_BIT, which are not ignored because of the
not matching '1000baseT' substring.

Add regex to match all ETHTOOL_LINK_MODE enums.

Link: https://lkml.kernel.org/r/20230104201524.28078-1-gerhard@engleder-embedded.com


Signed-off-by: Gerhard Engleder <gerhard@engleder-embedded.com>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Dwaipayan Ray <dwaipayanray1@gmail.com>
Cc: Gerhard Engleder <gerhard@engleder-embedded.com>
Cc: Joe Perches <joe@perches.com>
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Single-argument kvfree_rcu() usage is being deprecated [1] [2]. However,
till all users are converted, we would like to introduce checkpatch
errors for new patches submitted.

This patch adds support for the same. Tested with a trial patch.

For now, we are only considering usages that don't have compound
nesting, for example ignore: kvfree_rcu( (rcu_head_obj), rcu_head_name).
This is sufficient as such usages are unlikely.

Once all users are converted and we remove the old API, we can also revert this
checkpatch patch then.

[1] https://lore.kernel.org/rcu/CAEXW_YRhHaVuq+5f+VgCZM=SF+9xO+QXaxe0yE7oA9iCXK-XPg@mail.gmail.com/
[2] https://lore.kernel.org/rcu/CAEXW_YSY=q2_uaE2qo4XSGjzs4+C102YMVJ7kWwuT5LGmJGGew@mail.gmail.com/



Acked-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>

Privately, Heinz Mauelshagen showed that the embedded filename test is not
specific enough.

> WARNING: It's generally not useful to have the filename in the file
> #113: FILE: errors.c:113:
> +            block < registered_errors.blocks + registered_errors.count;

Extend the test to use the appropriate word boundary tests.

Link: https://lkml.kernel.org/r/36069dac5d07509dab1c7f1238f8cbb08db80ac6.camel@perches.com


Signed-off-by: Joe Perches <joe@perches.com>
Reported-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Instead of using an unnecessarily complicated approach to print a line
that is warned about, use `$herecurr` instead, just like everywhere else
in checkpatch.

While at it, remove a superfluous space in one of the changed lines, too. 
In a unmodified line also remove a superfluous check for a space before a
signed-off-by tag, to me consistent with the check at the start of the
section.

All three problems were found by Joe Perches during review of new code
inspired by the code modified here.

Link: https://lkml.kernel.org/r/a6d455c5196219b2095c2ac3645498052845f32e.1674217480.git.linux@leemhuis.info


Signed-off-by: Thorsten Leemhuis <linux@leemhuis.info>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Dwaipayan Ray <dwaipayanray1@gmail.com>
Cc: Joe Perches <joe@perches.com>
Cc: Kai Wasserbäch <kai@dev.carbon-project.org>
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Encourage patch authors to link to reports by issuing a warning, if a
Reported-by: is not accompanied by a link to the report.  Those links are
often extremely useful for any code archaeologist that wants to know more
about the backstory of a change than the commit message provides.  That
includes maintainers higher up in the patch-flow hierarchy, which is why
Linus asks developers to add such links [1, 2, 3].  To quote [1]:

> Again, the commit has a link to the patch *submission*, which is
> almost entirely useless. There's no link to the actual problem the
> patch fixes.
>
> [...]
>
> Put another way: I can see that
>
> Reported-by: Zhangfei Gao <zhangfei.gao@foxmail.com>
>
> in the commit, but I don't have a clue what the actual report was, and
> there really isn't enough information in the commit itself, except for
> a fairly handwavy "Device drivers might, for instance, still need to
> flush operations.."
>
> I don't want to know what device drivers _might_ do. I would want to
> have an actual pointer to what they do and where.

Another reason why these links are wanted: the ongoing regression tracking
efforts can only scale with them, as they allow the regression tracking
bot 'regzbot' to automatically connect tracked reports with patches that
are posted or committed to fix tracked regressions.

Link: https://lore.kernel.org/all/CAHk-=wjMmSZzMJ3Xnskdg4+GGz=5p5p+GSYyFBTh0f-DgvdBWg@mail.gmail.com/ [1]
Link: https://lore.kernel.org/all/CAHk-=wgs38ZrfPvy=nOwVkVzjpM3VFU1zobP37Fwd_h9iAD5JQ@mail.gmail.com/ [2]
Link: https://lore.kernel.org/all/CAHk-=wjxzafG-=J8oT30s7upn4RhBs6TX-uVFZ5rME+L5_DoJA@mail.gmail.com/ [3]
Link: https://lkml.kernel.org/r/bb5dfd55ea2026303ab2296f4a6df3da7dd64006.1674217480.git.linux@leemhuis.info


Signed-off-by: Kai Wasserbäch <kai@dev.carbon-project.org>
Co-developed-by: Thorsten Leemhuis <linux@leemhuis.info>
Signed-off-by: Thorsten Leemhuis <linux@leemhuis.info>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Dwaipayan Ray <dwaipayanray1@gmail.com>
Cc: Joe Perches <joe@perches.com>
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Patch series "checkpatch.pl: warn about discouraged tags and missing Link:
tags", v4.

The first two changes make checkpatch.pl check for a few mistakes wrt to
links to bug reports Linus recently complained about a few times. 
Avoiding those is also important for my regression tracking efforts a lot,
as the automated tracking performed by regzbot relies on the proper usage
of the Link: tag.

The third patch fixes a few small oddities noticed in existing code during
review of the two changes.


This patch (of 3):

Issue a warning when encountering URLs behind unknown tags, as Linus
recently stated ```please stop making up random tags that make no sense. 
Just use "Link:"```[1].  That statement was triggered by an use of
'BugLink', but that's not the only tag people invented:

$ git log -100000 --no-merges --format=email -P \
   --grep='^\w+:[ 	]*http' | grep -Poh '^\w+:[ 	]*http' | \
  sort | uniq -c | sort -rn | head -n 20
 103958 Link: http
    418 BugLink: http
    372 Patchwork: http
    280 Closes: http
    224 Bug: http
    123 References: http
     84 Bugzilla: http
     61 URL: http
     42 v1: http
     38 Datasheet: http
     20 v2: http
      9 Ref: http
      9 Fixes: http
      9 Buglink: http
      8 v3: http
      8 Reference: http
      7 See: http
      6 1: http
      5 link: http
      3 Link:http

Some of these non-standard tags make it harder for external tools that
rely on use of proper tags.  One of those tools is the regression tracking
bot 'regzbot', which looks out for "Link:" tags pointing to reports of
tracked regressions.

The initial idea was to use a disallow list to raise an error when
encountering known unwanted tags like BugLink:; during review it was
requested to use a list of allowed tags instead[2].

Link: https://lkml.kernel.org/r/cover.1674217480.git.linux@leemhuis.info
Link: https://lore.kernel.org/all/CAHk-=wgs38ZrfPvy=nOwVkVzjpM3VFU1zobP37Fwd_h9iAD5JQ@mail.gmail.com/ [1]
Link: https://lore.kernel.org/all/15f7df96d49082fb7799dda6e187b33c84f38831.camel@perches.com/ [2]
Link: https://lkml.kernel.org/r/3b036087d80b8c0e07a46a1dbaaf4ad0d018f8d5.1674217480.git.linux@leemhuis.info


Signed-off-by: Kai Wasserbäch <kai@dev.carbon-project.org>
Co-developed-by: Thorsten Leemhuis <linux@leemhuis.info>
Signed-off-by: Thorsten Leemhuis <linux@leemhuis.info>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Dwaipayan Ray <dwaipayanray1@gmail.com>
Cc: Joe Perches <joe@perches.com>
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

It was suggested by Fabio that kunmap() be marked deprecated in
checkpatch.[1] This did not seem necessary until an invalid conversion of
kmap_local_page() appeared in mainline.[2][3] The introduction of this bug
would have been flagged with kunmap() being marked deprecated.

Add kunmap() and kunmap_atomic() to checkpatch to help prevent further
confusion.

[1] https://lore.kernel.org/all/1884934.6tgchFWduM@suse/
[2] d406d267 ("cifs: skip alloc when request has no pages")
[3] https://lore.kernel.org/r/20221229-cifs-kmap-v1-1-c70d0e9a53eb@intel.com

Link: https://lkml.kernel.org/r/20221229-kmap-checkpatch-v2-1-919fc4d4e3c2@intel.com


Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Suggested-by: "Fabio M. De Francesco" <fmdefrancesco@gmail.com>
Acked-by: Joe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

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

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/
Link: https://lkml.kernel.org/r/20221104070523.60296-1-liaochang1@huawei.com


Signed-off-by: Liao Chang <liaochang1@huawei.com>
Acked-by: Joe Perches <joe@perches.com>
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Cc: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Bagas Sanjaya <bagasdotme@gmail.com>
Cc: Dwaipayan Ray <dwaipayanray1@gmail.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Do not report errors like below:

./scripts/checkpatch.pl -f drivers/net/wireless/ath/ath10k/wmi.h

ERROR: Macros with complex values should be enclosed in parentheses
+#define C2S(x) case x: return #x

since many "case ..." macros are already used by some in-kernel drivers.

Link: https://lkml.kernel.org/r/20221027134334.164301-1-stf_xl@wp.pl


Signed-off-by: Stanislaw Gruszka <stf_xl@wp.pl>
Acked-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

The lkml.org, marc.info, spinics.net, etc archives are not quite as useful
as lore.kernel.org because they use different styles, add advertising, and
may disappear in the future.  The lore archives are more consistent and
more likely to stick around, so prefer https://lore.kernel.org URLs when
they exist.

[bhelgaas@google.com: only warn if we see "http" before the archive hostname]
  Link: https://lkml.kernel.org/r/20221114224315.GA939630@bhelgaas
Link: https://lkml.kernel.org/r/20221019202843.40810-1-helgaas@kernel.org


Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Peter Collingbourne <pcc@google.com>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Dwaipayan Ray <dwaipayanray1@gmail.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Cc: Randy Dunlap <rdunlap@infradead.org> # build-tested
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Add a warning for fixes tags that does not follow community conventions.

Link: https://lkml.kernel.org/r/20220914100255.1048460-1-niklas.soderlund@corigine.com


Signed-off-by: Niklas Söderlund <niklas.soderlund@corigine.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: Louis Peens <louis.peens@corigine.com>
Reviewed-by: Philippe Schenker <philippe.schenker@toradex.com>
Acked-by: Dwaipayan Ray <dwaipayanray1@gmail.com>
Reviewed-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Acked-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Acked-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

checkpatch does not point out that VM_BUG_ON() and friends should be
avoided, however, Linus notes:

    VM_BUG_ON() has the exact same semantics as BUG_ON. It is literally
    no different, the only difference is "we can make the code smaller
    because these are less important". [1]

So let's warn on VM_BUG_ON() and other BUG variants as well. While at it,
make it clearer that the kernel really shouldn't be crashed.

As there are some subsystem BUG macros that actually don't end up crashing
the kernel -- for example, KVM_BUG_ON() -- exclude these manually.

[1] https://lore.kernel.org/r/CAHk-=wg40EAZofO16Eviaj7mfqDhZ2gVEbvfsMf6gYzspRjYvw@mail.gmail.com



Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20220923113426.52871-3-david@redhat.com


Signed-off-by: Jonathan Corbet <corbet@lwn.net>

This one file should not really be in the top-level documentation
directory.  core-api/ may not be a perfect fit but seems to be best, so
move it there.  Adjust a couple of internal document references to make
them location-independent, and point checkpatch.pl at the new location.

Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: Joe Perches <joe@perches.com>
Reviewed-by: David Vernet <void@manifault.com>
Acked-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Link: https://lore.kernel.org/r/20220927160559.97154-6-corbet@lwn.net


Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Include Rust in the "source code files" category, so that
the language-independent tests are checked for Rust too,
and teach `checkpatch` about the comment style for Rust files.

This enables the malformed SPDX check, the misplaced SPDX license
tag check, the long line checks, the lines without a newline check
and the embedded filename check.

Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Co-developed-by: Alex Gaynor <alex.gaynor@gmail.com>
Signed-off-by: Alex Gaynor <alex.gaynor@gmail.com>
Co-developed-by: Wedson Almeida Filho <wedsonaf@google.com>
Signed-off-by: Wedson Almeida Filho <wedsonaf@google.com>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

The `%pA` format specifier is only intended to be used from Rust.

`checkpatch.pl` already gives a warning for invalid specificers:

    WARNING: Invalid vsprintf pointer extension '%pA'

This makes it an error and introduces an explanatory message:

    ERROR: Invalid vsprintf pointer extension '%pA' - '%pA' is only intended to be used from Rust code

Suggested-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Co-developed-by: Alex Gaynor <alex.gaynor@gmail.com>
Signed-off-by: Alex Gaynor <alex.gaynor@gmail.com>
Co-developed-by: Wedson Almeida Filho <wedsonaf@google.com>
Signed-off-by: Wedson Almeida Filho <wedsonaf@google.com>
Co-developed-by: Joe Perches <joe@perches.com>
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

When using a "FILE *" type, checkpatch considers this an error:
  ERROR: need consistent spacing around '*' (ctx:WxV)
  #32: FILE: f.c:8:
  +static void a(FILE *const b)
                      ^

Fix this by explicitly defining "FILE" as a common type.  This is useful for
user space patches.

With this patch, we now get:
   <E> <E> <_>WS( )
   <E> <E> <_>IDENT(static)
   <E> <V> <_>WS( )
   <E> <V> <_>DECLARE(void )
   <E> <T> <_>FUNC(a)
   <E> <V> <V>PAREN('(')
   <EV> <N> <_>DECLARE(FILE *const )
   <EV> <T> <_>IDENT(b)
   <EV> <V> <_>PAREN(')') -> V
   <E> <V> <_>WS(
  )
  32 > . static void a(FILE *const b)
  32 > EEVVVVVVVTTTTTVNTTTTTTTTTTTTVVV
  32 >  ______________________________

Link: https://lkml.kernel.org/r/20220902111923.1488671-1-mic@digikod.net
Link: https://lore.kernel.org/r/20220902111923.1488671-1-mic@digikod.net


Signed-off-by: Mickaël Salaün <mic@digikod.net>
Acked-by: Joe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Dwaipayan Ray <dwaipayanray1@gmail.com>
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

kmap() and kmap_atomic() are being deprecated in favor of
kmap_local_page().

There are two main problems with kmap(): (1) It comes with an overhead as
mapping space is restricted and protected by a global lock for
synchronization and (2) it also requires global TLB invalidation when the
kmap's pool wraps and it might block when the mapping space is fully
utilized until a slot becomes available.

kmap_local_page() is safe from any context and is therefore redundant with
kmap_atomic() with the exception of any pagefault or preemption disable
requirements.  However, using kmap_atomic() for these side effects makes
the code less clear.  So any requirement for pagefault or preemption
disable should be made explicitly.

With kmap_local_page() the mappings are per thread, CPU local, can take
page faults, and can be called from any context (including interrupts). 
It is faster than kmap() in kernels with HIGHMEM enabled.  Furthermore,
the tasks can be preempted and, when they are scheduled to run again, the
kernel virtual addresses are restored.

Link: https://lkml.kernel.org/r/20220813220034.806698-1-ira.weiny@intel.com


Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Suggested-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

The code fragment below

	int foo(int *array, int index)
	{
		return array[index & 0xFF];
	}

triggers an incorrect camelcase detection by checking a substring of the
hex constant:

	CHECK: Avoid CamelCase: <xFF>
	#3: FILE: test.c:3:
	+	return array[index & 0xFF];

This is caused by passing the whole string "array[index & 0xFF]" to the
inner loop that iterates over a "$Ident" match.  The numeric constant is
not a $Ident as it doesn't start with [A-Za-z_] and should be excluded
from the match.

Similar issue can be detected with other constants like "1uL", "0xffffU".

Force the match to start at word boundary so the $Ident will be properly
checked starting from its first char and the constants will be
filtered-out.

Link: https://lkml.kernel.org/r/20220613100055.77821-1-borneo.antonio@gmail.com


Signed-off-by: Antonio Borneo <borneo.antonio@gmail.com>
Cc: Joe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Dwaipayan Ray <dwaipayanray1@gmail.com>
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

XA_STATE() and XA_STATE_ORDER macro uses are declarations.

Add them to the declaration macro list to avoid suggesting a blank line
after declarations when used.

Link: https://lkml.kernel.org/r/144314f4bf2c58cf2336028a75a5127e848abd81.camel@perches.com


Signed-off-by: Joe Perches <joe@perches.com>
Reported-by: David Howells <dhowells@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

kvmalloc() and kvzalloc() functions have now 2-factor multiplication
argument forms kvmalloc_array() and kvcalloc(), correspondingly.

Add alloc-with-multiplies checks for these new functions.

Link: https://github.com/KSPP/linux/issues/187


Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>

Commit 0ee3e7b8 ("checkpatch: get default codespell dictionary path
from package location") introduced the ability to search for the
codespell dictionary rather than hardcoding its path.

codespell requires Python 3.6 or above, but on some systems, the python
executable is a Python 2.7 interpreter.  In this case, searching for the
dictionary fails, subsequently making codespell fail:

  No codespell typos will be found - file '/usr/share/codespell/dictionary.txt': No such file or directory

So, use python3 to remove ambiguity.

In addition, when searching for dictionary.txt, do not check if the
codespell executable exists since,

 - checkpatch.pl only uses dictionary.txt, not the codespell
   executable.

 - codespell can be installed via a Python package manager, in which
   case the codespell executable may not be present in a typical $PATH,
   but a dictionary does exist.

Link: https://lkml.kernel.org/r/20220309180048.147672-1-sagarmp@cs.unc.edu


Signed-off-by: Sagar Patel <sagarmp@cs.unc.edu>
Reviewed-by: Peter Ujfalusi <peter.ujfalusi@linux.intel.com>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Add early_param as another exception to the blank line preferred after
function/struct/union declaration or definition test.

Link: https://lkml.kernel.org/r/3bd6ada59f411a7685d7e64eeb670540d4bfdcde.camel@perches.com


Signed-off-by: Joe Perches <joe@perches.com>
Cc: Dwaipayan Ray <dwaipayanray1@gmail.com>
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Single line code like:

	if (foo) bar;

should generally be written:

	if (foo)
		bar;

Add a --fix test to do so.

This fix is not done when an ASSIGN_IN_IF in the same line exists.

Link: https://lkml.kernel.org/r/20220128185924.80137-2-joe@perches.com


Signed-off-by: Joe Perches <joe@perches.com>
Cc: Dwaipayan Ray <dwaipayanray1@gmail.com>
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>