Add the _once and _ratelimited variants to the test for
printk(KERN_<LEVEL> that should prefer pr_<level>.

Miscellanea:

o Add comment description for the conversions

[joe@perches.com: fixlet]
  Link: https://lkml.kernel.org/r/32260871d4718ba7f48a8e9e07452bb76de300db.camel@perches.comLink: https://lkml.kernel.org/r/993b72b2ef91a57c5e725b52971ce3fd31375061.camel@perches.comSigned-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

checkpatch reports a false TYPO_SPELLING warning for some words containing
an apostrophe when run with --codespell option.

A false positive is "doesn't".  Occurrence of the word causes checkpatch
to emit the following warning:

"WARNING: 'doesn'' may be misspelled - perhaps 'doesn't'?"

Modify the regex pattern to be more in line with the codespell default
word matching regex.  This fixes the word capture and avoids the false
warning.

In addition, highlight the misspelled word location by adding a caret
below the word.

[akpm@linux-foundation.org: make matched misspelling more obvious, per Joe]
  Link: https://lkml.kernel.org/r/09c24ef1aa2f1c4fe909d76f5426f08780b9d81c.camel@perches.com

Link: https://lkml.kernel.org/r/20201201190729.169733-1-dwaipayanray1@gmail.comSigned-off-by: NDwaipayan Ray <dwaipayanray1@gmail.com>
Suggested-by: NJoe Perches <joe@perches.com>
Reported-by: NPeilin Ye <yepeilin.cs@gmail.com>
Acked-by: NJoe Perches <joe@perches.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Commit log lines starting with '#' are dropped by git as comments.
Add a check to emit a warning for these lines.

Also add a --fix option to insert a space before the leading '#' in
such lines.

Link: https://lkml.kernel.org/r/20201202205740.127986-1-dwaipayanray1@gmail.comSigned-off-by: NDwaipayan Ray <dwaipayanray1@gmail.com>
Suggested-by: NJoe Perches <joe@perches.com>
Suggested-by: NPeilin Ye <yepeilin.cs@gmail.com>
Tested-by: NPeilin Ye <yepeilin.cs@gmail.com>
Acked-by: NJoe Perches <joe@perches.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Modifiers %h and %hh should never be used.

Commit cbacb5ab ("docs: printk-formats: Stop encouraging use of
unnecessary %h[xudi] and %hh[xudi]") specifies that:

 "Standard integer promotion is already done and %hx and %hhx is useless
  so do not encourage the use of %hh[xudi] or %h[xudi]."

 "The "h" and "hh" things should never be used. The only reason for them
  being used if you have an "int", but you want to print it out as a
  "char" (and honestly, that is a really bad reason, you'd be better off
  just using a proper cast to make the code more obvious)."

Add a new check to emit a warning on finding an unneeded use of %h or
%hh modifier.

Also add a fix option to the check.

Link: https://lore.kernel.org/lkml/4910042649a4f3ab22fac93191b8c1fa0a2e17c3.camel@perches.com/
Link: https://lkml.kernel.org/r/20201128200046.78739-1-dwaipayanray1@gmail.comSigned-off-by: NDwaipayan Ray <dwaipayanray1@gmail.com>
Suggested-by: NJoe Perches <joe@perches.com>
Suggested-by: NLukas Bulwahn <lukas.bulwahn@gmail.com>
Acked-by: NJoe Perches <joe@perches.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Currently checkpatch warns for BAD_SIGN_OFF on non-standard signature
styles.

A large number of these warnings occur because of typo mistakes in
signature tags.  An evaluation over v4.13..v5.8 showed that out of 539
warnings due to non-standard signatures, 87 are due to typo mistakes.

Following are the standard signature tags which are often incorrectly
used, along with their individual counts of incorrect use (over
v4.13..v5.8):

 Reviewed-by: 42
 Signed-off-by: 25
 Reported-by: 6
 Acked-by: 4
 Tested-by: 4
 Suggested-by: 4

Provide a fix by calculating levenshtein distance for the signature tag
with all the standard signatures and suggest a fix with a signature, whose
edit distance is less than or equal to 2 with the misspelled signature.

Out of the 86 mispelled signatures fixed with this approach, 85 were found
to be good corrections and 1 was bad correction.

Following was found to be a bad correction:
 Tweeted-by (count: 1) => Tested-by

Link: https://lkml.kernel.org/r/20201128204333.7054-1-yashsri421@gmail.comSigned-off-by: NAditya Srivastava <yashsri421@gmail.com>
Acked-by: NJoe Perches <joe@perches.com>
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Currently, checkpatch warns if logical continuations are placed at the
start of a line and not at the end of previous line.

E.g., running checkpatch on commit 3485507f ("staging: bcm2835-camera:
Reduce length of enum names") reports:

  CHECK:LOGICAL_CONTINUATIONS: Logical continuations should be on the previous line
  +	if (!ret
  +	    && camera_port ==

Provide a simple fix by inserting logical operator at the last
non-comment, non-whitespace char of the previous line and removing from
current line, if both the lines are additions(ie start with '+')

Link: https://lkml.kernel.org/r/20201123102818.24364-1-yashsri421@gmail.comSigned-off-by: NAditya Srivastava <yashsri421@gmail.com>
Acked-by: NJoe Perches <joe@perches.com>
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Currently, checkpatch warns us if an assignment operator is placed at the
start of a line and not at the end of previous line.

E.g., running checkpatch on commit 8195b139 ("hv_netvsc: fix
deadlock on hotplug") reports:

  CHECK: Assignment operator '=' should be on the previous line
  +	struct netvsc_device *nvdev
  +		= container_of(w, struct netvsc_device, subchan_work);

Provide a simple fix by appending assignment operator to the previous
line and removing from the current line, if both the lines are additions
(ie start with '+')

Link: https://lkml.kernel.org/r/20201121120407.22942-1-yashsri421@gmail.comSigned-off-by: NAditya Srivastava <yashsri421@gmail.com>
Acked-by: NJoe Perches <joe@perches.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

There is an unescaped left brace in a regex in OPEN_BRACE check.  This
throws a runtime error when checkpatch is run with --fix flag and the
OPEN_BRACE check is executed.

Fix it by escaping the left brace.

Link: https://lkml.kernel.org/r/20201115202928.81955-1-dwaipayanray1@gmail.com
Fixes: 8d182478 ("checkpatch: add --fix option for a couple OPEN_BRACE misuses")
Signed-off-by: NDwaipayan Ray <dwaipayanray1@gmail.com>
Acked-by: NJoe Perches <joe@perches.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Currently checkpatch warns us for long lines in commits even for signature
tag lines.

Generally these lines exceed the 75-character limit because of:

 1) long names and long email address

 2) some comments on scoped review and acknowledgement, i.e., for a
    dedicated pointer on what was reported by the identity in
    'Reported-by'

 3) some additional comments on CC: stable@vger.org tags

Exclude signature tag lines from this class of warning.

There were 1896 COMMIT_LOG_LONG_LINE warnings in v5.6..v5.8 before this
patch application and 1879 afterwards.

A quick manual check found all the dropped warnings related to signature
tags.

Link: https://lkml.kernel.org/r/20201116083754.10629-1-yashsri421@gmail.comSigned-off-by: NAditya Srivastava <yashsri421@gmail.com>
Acked-by: NJoe Perches <joe@perches.com>
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Delete repeated word in scripts/checkpatch.pl:
  "are are" -> "are"

Fix typos:
  "commments" -> "comments"
  "falsly" -> "falsely"

Link: https://lkml.kernel.org/r/20201113152316.62975-1-dwaipayanray1@gmail.comSigned-off-by: NDwaipayan Ray <dwaipayanray1@gmail.com>
Acked-by: NJoe Perches <joe@perches.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

checkpatch doesn't report warnings for many common mistakes in emails.
Some of which are trailing commas and incorrect use of email comments.

At the same time several false positives are reported due to incorrect
handling of mail comments.  The most common of which is due to the
pattern:

<stable@vger.kernel.org> # X.X

Improve email parsing in checkpatch.

Some general email rules are defined:

- Multiple name comments should not be allowed.
- Comments inside address should not be allowed.
- In general comments should be enclosed within parentheses.
  Relaxation is given to comments beginning with #.
- Stable addresses should not begin with a name.
- Comments in stable addresses should begin only
  with a #.

Improvements to parsing:

- Detect and report unexpected content after email.
- Quoted names are excluded from comment parsing.
- Trailing dots, commas or quotes in email are removed during
  formatting. Correspondingly a BAD_SIGN_OFF warning
  is emitted.
- Improperly quoted email like '"name <address>"' are now
  warned about.

In addition, added fixes for all the possible rules.

Link: https://lore.kernel.org/linux-kernel-mentees/6c275d95c3033422addfc256a30e6ae3dd37941d.camel@perches.com/
Link: https://lore.kernel.org/linux-kernel-mentees/20201105200857.GC1333458@kroah.com/
Link: https://lkml.kernel.org/r/20201108100632.75340-1-dwaipayanray1@gmail.comSigned-off-by: NDwaipayan Ray <dwaipayanray1@gmail.com>
Suggested-by: NJoe Perches <joe@perches.com>
Acked-by: NJoe Perches <joe@perches.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add __alias and __weak to the suggested __attribute__((<foo>))
conversions.

Link: https://lkml.kernel.org/r/7b74137743c58ce0633ec4d575b94e2210e4dbe7.camel@perches.comSigned-off-by: NJoe Perches <joe@perches.com>
Cc: Dwaipayan Ray <dwaipayanray1@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Currently, whenever a Gerrit Change-Id is present in a commit,
checkpatch.pl warns to remove the Change-Id before submitting the patch.

E.g., running checkpatch on commit adc311a5 ("iwlwifi: bump FW
API to 53 for 22000 series") reports this error:

  ERROR: Remove Gerrit Change-Id's before submitting upstream
  Change-Id: I5725e46394f3f53c3069723fd513cc53c7df383d

Provide a simple fix option by simply deleting the indicated line.

Link: https://lkml.kernel.org/r/20201030114447.24199-1-yashsri421@gmail.comSigned-off-by: NAditya Srivastava <yashsri421@gmail.com>
Acked-by: NJoe Perches <joe@perches.com>
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

commit 33def849 ("treewide: Convert macro and uses of
__section(foo) to __section("foo")") removed the stringification of the
section name and now requires quotes around the named section.

Update checkpatch to not remove any quotes when suggesting conversion
of __attribute__((section("name"))) to __section("name")

Miscellanea:

o Add section to the hash with __section replacement
o Remove separate test for __attribute__((section
o Remove the limitation on converting attributes containing only
  known, possible conversions.  Any unknown attribute types are now
  left as-is and known types are converted and moved before
  __attribute__ and removed from within the __attribute__((list...)).

[joe@perches.com: eliminate the separate test below the possible conversions loop]
  Link: https://lkml.kernel.org/r/58e9d55e933dc8fdc6af489f2ad797fa8eb13e44.camel@perches.com

Link: https://lkml.kernel.org/r/c04dd1c810e8d6a68e6a632e3191ae91651c8edf.camel@perches.comSigned-off-by: NJoe Perches <joe@perches.com>
Cc: Dwaipayan Ray <dwaipayanray1@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Remove the trailing error message from the fixed lines.

Link: https://lkml.kernel.org/r/20201017142546.28988-1-trix@redhat.comSigned-off-by: NTom Rix <trix@redhat.com>
Acked-by: NJoe Perches <joe@perches.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

It is generally preferred that the macros from
include/linux/compiler_attributes.h are used, unless there is a reason not
to.

checkpatch currently checks __attribute__ for each of packed, aligned,
section, printf, scanf, and weak.  Other declarations in
compiler_attributes.h are not handled.

Add a generic test to check the presence of such attributes.  Some
attributes require more specific handling and are kept separate.

Also add fixes to the generic attributes check to substitute the correct
conversions.

New attributes which are now handled are:

__always_inline__
__assume_aligned__(a, ## __VA_ARGS__)
__cold__
__const__
__copy__(symbol)
__designated_init__
__externally_visible__
__gnu_inline__
__malloc__
__mode__(x)
__no_caller_saved_registers__
__noclone__
__noinline__
__nonstring__
__noreturn__
__pure__
__unused__
__used__

Declarations which contain multiple attributes like
__attribute__((__packed__, __cold__)) are also handled except when proper
conversions for one or more attributes of the list cannot be determined.

Link: https://lore.kernel.org/linux-kernel-mentees/3ec15b41754b01666d94b76ce51b9832c2dd577a.camel@perches.com/
Link: https://lkml.kernel.org/r/20201025193103.23223-1-dwaipayanray1@gmail.comSigned-off-by: NDwaipayan Ray <dwaipayanray1@gmail.com>
Suggested-by: NJoe Perches <joe@perches.com>
Acked-by: NJoe Perches <joe@perches.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

switch/case use of break after a return, goto or break is unnecessary.

There is an existing warning for the return and goto uses, so add
break and a --fix option too.

Link: https://lkml.kernel.org/r/d9ea654104d55f590fb97d252d64a66b23c1a096.camel@perches.comSigned-off-by: NJoe Perches <joe@perches.com>
Cc: Julia Lawall <julia.lawall@inria.fr>
Cc: Tom Rix <trix@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

There are about 100,000 uses of 'static const <type>' but about 400 uses
of 'static <type> const' in the kernel where type is not a pointer.

The kernel almost always uses "static const" over "const static" as there
is a compiler warning for that declaration style.

But there is no compiler warning for "static <type> const".

So add a checkpatch warning for the atypical declaration uses of.

	const static <type> <foo>
and
	static <type> const <foo>

For example:

  $ ./scripts/checkpatch.pl -f --emacs --quiet --nosummary -types=static_const arch/arm/crypto/aes-ce-glue.c
  arch/arm/crypto/aes-ce-glue.c:75: WARNING: Move const after static - use 'static const u8'
  #75: FILE: arch/arm/crypto/aes-ce-glue.c:75:
  +	static u8 const rcon[] = {

Link: https://lkml.kernel.org/r/4b863be68e679546b40d50b97a4a806c03056a1c.camel@perches.comSigned-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Ignore autogenerated CamelCase-like defines and enum values like
DRM_MODE_CONNECTOR_Unknown or ETHTOOL_LINK_MODE_Asym_Pause_BIT.

Link: https://lkml.kernel.org/r/20201022184916.7904-1-l.stelmach@samsung.comSigned-off-by: NŁukasz Stelmach <l.stelmach@samsung.com>
Suggested-by: NJoe Perches <joe@perches.com>
Acked-by: NJoe Perches <joe@perches.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Presence of hexadecimal address or symbol results in false warning
message by checkpatch.pl.

For example, running checkpatch on commit b8ad540d ("mptcp: fix
memory leak in mptcp_subflow_create_socket()") results in warning:

  WARNING:REPEATED_WORD: Possible repeated word: 'ff'
      00 00 00 00 00 00 00 00 00 2f 30 0a 81 88 ff ff  ........./0.....

Similarly, the presence of list command output in commit results in
an unnecessary warning.

For example, running checkpatch on commit 899e5ffb ("perf record:
Introduce --switch-output-event") gives:

  WARNING:REPEATED_WORD: Possible repeated word: 'root'
    dr-xr-x---. 12 root root    4096 Apr 27 17:46 ..

Here, it reports 'ff' and 'root' to be repeated, but it is in fact part
of some address or code, where it has to be repeated.

In these cases, the intent of the warning to find stylistic issues in
commit messages is not met and the warning is just completely wrong in
this case.

To avoid these warnings, add an additional regex check for the directory
permission pattern and avoid checking the line for this class of
warning.  Similarly, to avoid hex pattern, check if the word consists of
hex symbols and skip this warning if it is not among the common english
words formed using hex letters.

A quick evaluation on v5.6..v5.8 showed that this fix reduces
REPEATED_WORD warnings by the frequency of 1890.

A quick manual check found all cases are related to hex output or list
command outputs in commit messages.

Link: https://lkml.kernel.org/r/20201024102253.13614-1-yashsri421@gmail.comSigned-off-by: NAditya Srivastava <yashsri421@gmail.com>
Acked-by: NJoe Perches <joe@perches.com>
Cc: Dwaipayan Ray <dwaipayanray1@gmail.com>
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Recently, commit 4f6ad8aa1eac ("checkpatch: move repeated word test")
moved the repeated word test to check for more file types. But after
this, if checkpatch.pl is run on MAINTAINERS, it generates several
new warnings of the type:

  WARNING: Possible repeated word: 'git'

For example:

  WARNING: Possible repeated word: 'git'
  +T:	git git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml.git

So, the pattern "git git://..." is a false positive in this case.

There are several other combinations which may produce a wrong warning
message, such as "@size size", ":Begin begin", etc.

Extend repeated word check to compare the characters before and after
the word matches.

If there is a non whitespace character before the first word or a non
whitespace character excluding punctuation characters after the second
word, then the check is skipped and the warning is avoided.

Also add case insensitive word matching to the repeated word check.

Link: https://lore.kernel.org/linux-kernel-mentees/81b6a0bb2c7b9256361573f7a13201ebcd4876f1.camel@perches.com/
Link: https://lkml.kernel.org/r/20201017162732.152351-1-dwaipayanray1@gmail.comSigned-off-by: NDwaipayan Ray <dwaipayanray1@gmail.com>
Suggested-by: NJoe Perches <joe@perches.com>
Suggested-by: NLukas Bulwahn <lukas.bulwahn@gmail.com>
Acked-by: NJoe Perches <joe@perches.com>
Cc: Aditya Srivastava <yashsri421@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

If set, use the environment variable GIT_DIR to change the default .git
location of the kernel git tree.

If GIT_DIR is unset, keep using the current ".git" default.

Link: https://lkml.kernel.org/r/c5e23b45562373d632fccb8bc04e563abba4dd1d.camel@perches.comSigned-off-by: NJoe Perches <joe@perches.com>
Tested-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The author signed-off-by checks are currently very vague.  Cases like same
name or same address are not handled separately.

For example, running checkpatch on commit be6577af ("parisc: Add
atomic64_set_release() define to avoid CPU soft lockups"), gives:

WARNING: Missing Signed-off-by: line by nominal patch author
'John David Anglin <dave.anglin@bell.net>'

The signoff line was:
"Signed-off-by: Dave Anglin <dave.anglin@bell.net>"

Clearly the author has signed off but with a slightly different version
of his name. A more appropriate warning would have been to point out
at the name mismatch instead.

Previously, the values assumed by $authorsignoff were either 0 or 1
to indicate whether a proper sign off by author is present.
Extended the checks to handle four new cases.

$authorsignoff values now denote the following:

0: Missing sign off by patch author.

1: Sign off present and identical.

2: Addresses and names match, but comments differ.
   "James Watson(JW) <james@gmail.com>", "James Watson <james@gmail.com>"

3: Addresses match, but names are different.
   "James Watson <james@gmail.com>", "James <james@gmail.com>"

4: Names match, but addresses are different.
   "James Watson <james@watson.com>", "James Watson <james@gmail.com>"

5: Names match, addresses excluding subaddress details (RFC 5233) match.
   "James Watson <james@gmail.com>", "James Watson <james+a@gmail.com>"

Also introduced a new message type FROM_SIGN_OFF_MISMATCH
for cases 2, 3, 4 and 5.
Suggested-by: NJoe Perches <joe@perches.com>
Signed-off-by: NDwaipayan Ray <dwaipayanray1@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Acked-by: NJoe Perches <joe@perches.com>
Link: https://lore.kernel.org/linux-kernel-mentees/c1ca28e77e8e3bfa7aadf3efa8ed70f97a9d369c.camel@perches.com/
Link: https://lkml.kernel.org/r/20201007192029.551744-1-dwaipayanray1@gmail.comSigned-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

To avoid false positives in presence of SPDX-License-Identifier in
networking files it is required to increase the leeway for empty block
comment lines by one line.

For example, checking drivers/net/loopback.c which starts with

    // SPDX-License-Identifier: GPL-2.0-or-later
    /*
     * INET          An implementation of the TCP/IP protocol suite for the LINUX

rsults in an unnecessary warning

    WARNING: networking block comments don't use an empty /* line, use /* Comment...
    +/*
    + * INET                An implementation of the TCP/IP protocol suite for the LINUX
Signed-off-by: NŁukasz Stelmach <l.stelmach@samsung.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Acked-by: NJoe Perches <joe@perches.com>
Cc: Bartłomiej Żolnierkiewicz  <b.zolnierkie@samsung.co>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Link: https://lkml.kernel.org/r/20201006083509.19934-1-l.stelmach@samsung.comSigned-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Checkpatch.pl doesn't have a check for excluding while (...) {...} blocks
from MULTISTATEMENT_MACRO_USE_DO_WHILE error.

For example, running checkpatch.pl on the file mm/maccess.c in the kernel
generates the following error:

ERROR: Macros with complex values should be enclosed in parentheses
+#define copy_from_kernel_nofault_loop(dst, src, len, type, err_label)  \
+       while (len >= sizeof(type)) {                                   \
+               __get_kernel_nofault(dst, src, type, err_label);        \
+               dst += sizeof(type);                                    \
+               src += sizeof(type);                                    \
+               len -= sizeof(type);                                    \
+       }

The error is misleading for this case.  Enclosing it in parentheses
doesn't make any sense.

Checkpatch already has an exception list for such common macro types.
Added a new exception for while (...) {...} style blocks to the same.

In addition, the brace flatten logic was modified by changing the
substitution characters from "1" to "1u".  This was done to ensure that
macros in the form "#define foo(bar) while(bar){bar--;}" were also
correctly procecssed.

Link: https://lore.kernel.org/linux-kernel-mentees/dc985938aa3986702815a0bd68dfca8a03c85447.camel@perches.com/Suggested-by: NJoe Perches <joe@perches.com>
Signed-off-by: NDwaipayan Ray <dwaipayanray1@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Link: https://lkml.kernel.org/r/20201001171903.312021-1-dwaipayanray1@gmail.comSigned-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Embedding the complete filename path inside the file isn't particularly
useful as often the path is moved around and becomes incorrect.

Emit a warning when the source contains the filename.

[akpm@linux-foundation.org: remove stray " di"]
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Link: https://lkml.kernel.org/r/1fd5f9188a14acdca703ca00301ee323de672a8d.camel@perches.comSigned-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Checkpatch did not handle cases where the author From: header was split
into multiple lines.  The author identity could not be resolved and
checkpatch generated a false NO_AUTHOR_SIGN_OFF warning.

A typical example is commit e33bcbab ("tee: add support for session's
client UUID generation").  When checkpatch was run on this commit, it
displayed:

"WARNING:NO_AUTHOR_SIGN_OFF: Missing Signed-off-by: line by nominal
patch author ''"

This was due to split header lines not being handled properly and the
author himself wrote in commit cd261496 ("checkpatch: warn if missing
author Signed-off-by"):

"Split From: headers are not fully handled: only the first part
is compared."

Support split From: headers by correctly parsing the header extension
lines.  RFC 5322, Section-2.2.3 stated that each extended line must start
with a WSP character (a space or htab).  The solution was therefore to
concatenate the lines which start with a WSP to get the correct long
header.
Suggested-by: NJoe Perches <joe@perches.com>
Signed-off-by: NDwaipayan Ray <dwaipayanray1@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Tested-by: NLukas Bulwahn <lukas.bulwahn@gmail.com>
Reviewed-by: NLukas Bulwahn <lukas.bulwahn@gmail.com>
Acked-by: NJoe Perches <joe@perches.com>
Link: https://lore.kernel.org/linux-kernel-mentees/f5d8124e54a50480b0a9fa638787bc29b6e09854.camel@perches.com/
Link: https://lkml.kernel.org/r/20200921085436.63003-1-dwaipayanray1@gmail.comSigned-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

If a file exists in git and checkpatch is used without the -f flag for
scanning a file, then checkpatch will scan the file assuming it's a patch
and emit:

ERROR: Does not appear to be a unified-diff format patch

Change the behavior to assume the -f flag if the file exists in git.

[joe@perches.com: fix git "fatal" warning if file argument outside kernel tree]
  Link: https://lkml.kernel.org/r/b6afa04112d450c2fc120a308d706acd60cee294.camel@perches.comSigned-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Reviewed-by: NJulia Lawall <julia.lawall@inria.fr>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Link: https://lkml.kernel.org/r/45b81a48e1568bd0126a96f5046eb7aaae9b83c9.camel@perches.comSigned-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The uninitialized_var() macro was removed recently via commit 63a0895d
("compiler: Remove uninitialized_var() macro") as it's not a particularly
useful warning and its use can "paper over real bugs".

Add a checkpatch test to warn on self-assignments as a means to avoid
compiler warnings and as a back-door mechanism to reproduce the old
uninitialized_var macro behavior.

[akpm@linux-foundation.org: coding style fixes]
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Gustavo A. R. Silva <gustavoars@kernel.org>
Cc: Denis Efremov <efremov@linux.com>
Cc: Julia Lawall <julia.lawall@inria.fr>
Link: https://lkml.kernel.org/r/afc2cffdd315d3e4394af149278df9e8af7f49f4.camel@perches.comSigned-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

trace_printk is meant as a debugging tool, and should not be compiled into
production code without specific debug Kconfig options enabled, or source
code changes, as indicated by the warning that shows up on boot if any
trace_printk is called:

 **   NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE   **
 **                                                      **
 ** trace_printk() being used. Allocating extra memory.  **
 **                                                      **
 ** This means that this is a DEBUG kernel and it is     **
 ** unsafe for production use.                           **

Let's warn developers when they try to submit such a change.
Signed-off-by: NNicolas Boichat <drinkcat@chromium.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Joe Perches <joe@perches.com>
Link: https://lkml.kernel.org/r/20200825193600.v2.1.I723c43c155f02f726c97501be77984f1e6bb740a@changeidSigned-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

There are commas used as statement terminations that should typically have
used semicolons instead.  Only direct assignments or use of a single
function or value on a single line are detected by this test.

e.g.:
	foo = bar(),		/* typical use is semicolon not comma */
	bar = baz();

Add an imperfect test to detect these comma uses.

No false positives were found in testing, but many types of false
negatives are possible.

e.g.:
	foo = bar() + 1,	/* comma use, but not direct assignment */
	bar = baz();
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Link: https://lkml.kernel.org/r/3bf27caf462007dfa75647b040ab3191374a59de.camel@perches.comSigned-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Currently this test only works on .[ch] files.

Move the test to check more file types and the commit log.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/180b3b5677771c902b2e2f7a2b7090ede65fe004.camel@perches.comSigned-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Kconfig allows to customize the CONFIG_ prefix via the $CONFIG_
environment variable.  Out-of-tree projects may therefore use Kconfig with
a different prefix, or they may use a custom configuration tool which does
not use the CONFIG_ prefix at all.  Such projects may still want to adhere
to the Linux kernel coding style and run checkpatch.pl.

One example is OP-TEE [1] which does not use Kconfig but does have
configuration options prefixed with CFG_.  It also mostly follows the
kernel coding style and therefore being able to use checkpatch is quite
valuable.

To make this possible, add the --kconfig-prefix command line option.

[1] https://github.com/OP-TEE/optee_osSigned-off-by: NJerome Forissier <jerome@forissier.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Acked-by: NJoe Perches <joe@perches.com>
Link: http://lkml.kernel.org/r/20200818081732.800449-1-jerome@forissier.orgSigned-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The usage of "capture group (...)" in the immediate condition after `&&`
results in `$1` being uninitialized.  This issues a warning "Use of
uninitialized value $1 in regexp compilation at ./scripts/checkpatch.pl
line 2638".

I noticed this bug while running checkpatch on the set of commits from
v5.7 to v5.8-rc1 of the kernel on the commits with a diff content in
their commit message.

This bug was introduced in the script by commit e518e9a5
("checkpatch: emit an error when there's a diff in a changelog").  It
has been in the script since then.

The author intended to store the match made by capture group in variable
`$1`.  This should have contained the name of the file as `[\w/]+`
matched.  However, this couldn't be accomplished due to usage of capture
group and `$1` in the same regular expression.

Fix this by placing the capture group in the condition before `&&`.
Thus, `$1` can be initialized to the text that capture group matches
thereby setting it to the desired and required value.

Fixes: e518e9a5 ("checkpatch: emit an error when there's a diff in a changelog")
Signed-off-by: NMrinal Pandey <mrinalmni@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Tested-by: NLukas Bulwahn <lukas.bulwahn@gmail.com>
Reviewed-by: NLukas Bulwahn <lukas.bulwahn@gmail.com>
Cc: Joe Perches <joe@perches.com>
Link: https://lkml.kernel.org/r/20200714032352.f476hanaj2dlmiot@mrinalpandeySigned-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This reverts commit 84af7a61.

The conversion is done.

Cc: Ulf Magnusson <ulfalizer@gmail.com>
Signed-off-by: NMasahiro Yamada <masahiroy@kernel.org>

This test doesn't work well and newer compilers are much better
at emitting this warning.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Cc: Cambda Zhu <cambda@linux.alibaba.com>
Link: http://lkml.kernel.org/r/7e25090c79f6a69d502ab8219863300790192fe2.camel@perches.comSigned-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Try to avoid adding repeated words either on the same line or consecutive
comment lines in a block

e.g.:

duplicated word in comment block

	/*
	 * this is a comment block where the last word of the previous
	 * previous line is also the first word of the next line
	 */

and simple duplication

	/* test this this again */
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/cda9b566ad67976e1acd62b053de50ee44a57250.camel@perches.comInspired-by: NRandy Dunlap <rdunlap@infradead.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Checkpatch reports warnings when some specific structs are not declared as
const in the code.  The list of structs to consider was initially defined
in the checkpatch.pl script itself, but it was later moved to an external
file (scripts/const_structs.checkpatch), in commit bf1fa1da
("checkpatch: externalize the structs that should be const").  This
introduced two minor issues:

- When file scripts/const_structs.checkpatch is not present (for
  example, if checkpatch is run outside of the kernel directory with the
  "--no-tree" option), a warning is printed to stderr to tell the user
  that "No structs that should be const will be found". This is fair,
  but the warning is printed unconditionally, even if the option
  "--ignore CONST_STRUCT" is passed. In the latter case, we explicitly
  ask checkpatch to skip this check, so no warning should be printed.

- When scripts/const_structs.checkpatch is missing, or even when trying
  to silence the warning by adding an empty file, $const_structs is set
  to "", and the regex used for finding structs that should be const,
  "$line =~ /struct\s+($const_structs)(?!\s*\{)/)", matches all
  structs found in the code, thus reporting a number of false positives.

Let's fix the first item by skipping scripts/const_structs.checkpatch
processing if "CONST_STRUCT" checks are ignored, and the second one by
skipping the test if $const_structs is not defined. Since we modify the
read_words() function a little bit, update the checks for
$typedefsfile/$typeOtherTypedefs as well.
Signed-off-by: NQuentin Monnet <quentin@isovalent.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Acked-by: NJoe Perches <joe@perches.com>
Link: http://lkml.kernel.org/r/20200623221822.3727-1-quentin@isovalent.comSigned-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add a --fix option for 2 types of single-line assignment in if statements

	if ((foo = bar(...)) < BAZ) {
expands to:
	foo = bar(..);
	if (foo < BAZ) {
and
	if ((foo = bar(...)) {
expands to:
	foo = bar(...);
	if (foo) {

if statements with assignments spanning multiple lines are
not converted with the --fix option.

if statements with additional logic are also not converted.

e.g.:	if ((foo = bar(...)) & BAZ == BAZ) {
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Cc: Julia Lawall <julia.lawall@lip6.fr>
Link: http://lkml.kernel.org/r/9bc7c782516f37948f202deba511bc95ed279bbd.camel@perches.comSigned-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

IS_ENABLED is almost always used with CONFIG_<FOO> defines.

Add a test to verify that the #define being tested starts with CONFIG_.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Reviewed-by: NKees Cook <keescook@chromium.org>
Link: http://lkml.kernel.org/r/e7fda760b91b769ba82844ba282d432c0d26d709.camel@perches.comSigned-off-by: NLinus Torvalds <torvalds@linux-foundation.org>