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-rw-r--r--Documentation/dev-tools/checkpatch.rst80
1 files changed, 51 insertions, 29 deletions
diff --git a/Documentation/dev-tools/checkpatch.rst b/Documentation/dev-tools/checkpatch.rst
index abb3ff682076..dccede68698c 100644
--- a/Documentation/dev-tools/checkpatch.rst
+++ b/Documentation/dev-tools/checkpatch.rst
@@ -342,24 +342,6 @@ API usage
See: https://www.kernel.org/doc/html/latest/RCU/whatisRCU.html#full-list-of-rcu-apis
- **DEPRECATED_VARIABLE**
- EXTRA_{A,C,CPP,LD}FLAGS are deprecated and should be replaced by the new
- flags added via commit f77bf01425b1 ("kbuild: introduce ccflags-y,
- asflags-y and ldflags-y").
-
- The following conversion scheme maybe used::
-
- EXTRA_AFLAGS -> asflags-y
- EXTRA_CFLAGS -> ccflags-y
- EXTRA_CPPFLAGS -> cppflags-y
- EXTRA_LDFLAGS -> ldflags-y
-
- See:
-
- 1. https://lore.kernel.org/lkml/20070930191054.GA15876@uranus.ravnborg.org/
- 2. https://lore.kernel.org/lkml/1313384834-24433-12-git-send-email-lacombar@gmail.com/
- 3. https://www.kernel.org/doc/html/latest/kbuild/makefiles.html#compilation-flags
-
**DEVICE_ATTR_FUNCTIONS**
The function names used in DEVICE_ATTR is unusual.
Typically, the store and show functions are used with <attr>_store and
@@ -479,16 +461,9 @@ Comments
line comments is::
/*
- * This is the preferred style
- * for multi line comments.
- */
-
- The networking comment style is a bit different, with the first line
- not empty like the former::
-
- /* This is the preferred comment style
- * for files in net/ and drivers/net/
- */
+ * This is the preferred style
+ * for multi line comments.
+ */
See: https://www.kernel.org/doc/html/latest/process/coding-style.html#commenting
@@ -513,6 +488,15 @@ Comments
See: https://lore.kernel.org/lkml/20131006222342.GT19510@leaf/
+ **UNCOMMENTED_RGMII_MODE**
+ Historically, the RGMII PHY modes specified in Device Trees have been
+ used inconsistently, often referring to the usage of delays on the PHY
+ side rather than describing the board.
+
+ PHY modes "rgmii", "rgmii-rxid" and "rgmii-txid" modes require the clock
+ signal to be delayed on the PCB; this unusual configuration should be
+ described in a comment. If they are not (meaning that the delay is realized
+ internally in the MAC or PHY), "rgmii-id" is the correct PHY mode.
Commit message
--------------
@@ -617,6 +601,11 @@ Commit message
See: https://www.kernel.org/doc/html/latest/process/submitting-patches.html#describe-your-changes
+ **BAD_COMMIT_SEPARATOR**
+ The commit separator is a single line with 3 dashes.
+ The regex match is '^---$'
+ Lines that start with 3 dashes and have more content on the same line
+ may confuse tools that apply patches.
Comparison style
----------------
@@ -769,7 +758,7 @@ Macros, Attributes and Symbols
sizeof(foo)/sizeof(foo[0]) for finding number of elements in an
array.
- The macro is defined in include/linux/kernel.h::
+ The macro is defined in include/linux/array_size.h::
#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
@@ -1018,6 +1007,29 @@ Functions and Variables
return bar;
+ **UNINITIALIZED_PTR_WITH_FREE**
+ Pointers with __free attribute should be declared at the place of use
+ and initialized (see include/linux/cleanup.h). In this case
+ declarations at the top of the function rule can be relaxed. Not doing
+ so may lead to undefined behavior as the memory assigned (garbage,
+ in case not initialized) to the pointer is freed automatically when
+ the pointer goes out of scope.
+
+ Also see: https://lore.kernel.org/lkml/58fd478f408a34b578ee8d949c5c4b4da4d4f41d.camel@HansenPartnership.com/
+
+ Example::
+
+ type var __free(free_func);
+ ... // var not used, but, in future someone might add a return here
+ var = malloc(var_size);
+ ...
+
+ should be initialized as::
+
+ ...
+ type var __free(free_func) = malloc(var_size);
+ ...
+
Permissions
-----------
@@ -1254,6 +1266,16 @@ Others
The patch file does not appear to be in unified-diff format. Please
regenerate the patch file before sending it to the maintainer.
+ **PLACEHOLDER_USE**
+ Detects unhandled placeholder text left in cover letters or commit headers/logs.
+ Common placeholders include lines like::
+
+ *** SUBJECT HERE ***
+ *** BLURB HERE ***
+
+ These typically come from autogenerated templates. Replace them with a proper
+ subject and description before sending.
+
**PRINTF_0XDECIMAL**
Prefixing 0x with decimal output is defective and should be corrected.