1 Linux Kernel patch submission checklist
2 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
4 Here are some basic things that developers should do if they want to see their
5 kernel patch submissions accepted more quickly.
7 These are all above and beyond the documentation that is provided in
8 Documentation/SubmittingPatches
9 and elsewhere regarding submitting Linux kernel patches.
12 1) If you use a facility then #include the file that defines/declares
13 that facility. Don't depend on other header files pulling in ones
18 a) with applicable or modified ``CONFIG`` options ``=y``, ``=m``, and
19 ``=n``. No ``gcc`` warnings/errors, no linker warnings/errors.
21 b) Passes ``allnoconfig``, ``allmodconfig``
23 c) Builds successfully when using ``O=builddir``
25 3) Builds on multiple CPU architectures by using local cross-compile tools
26 or some other build farm.
28 4) ppc64 is a good architecture for cross-compilation checking because it
29 tends to use ``unsigned long`` for 64-bit quantities.
31 5: Check your patch for general style as detailed in
32 Documentation/CodingStyle.
33 Check for trivial violations with the patch style checker prior to
34 submission (``scripts/checkpatch.pl``).
35 You should be able to justify all violations that remain in
38 6) Any new or modified ``CONFIG`` options don't muck up the config menu.
40 7) All new ``Kconfig`` options have help text.
42 8) Has been carefully reviewed with respect to relevant ``Kconfig``
43 combinations. This is very hard to get right with testing -- brainpower
46 9) Check cleanly with sparse.
48 10) Use ``make checkstack`` and ``make namespacecheck`` and fix any problems
53 ``checkstack`` does not point out problems explicitly,
54 but any one function that uses more than 512 bytes on the stack is a
57 11: Include :ref:`kernel-doc <kernel_doc>` to document global kernel APIs.
58 (Not required for static functions, but OK there also.) Use
59 ``make htmldocs`` or ``make pdfdocs`` to check the
60 :ref:`kernel-doc <kernel_doc>` and fix any issues.
62 12) Has been tested with ``CONFIG_PREEMPT``, ``CONFIG_DEBUG_PREEMPT``,
63 ``CONFIG_DEBUG_SLAB``, ``CONFIG_DEBUG_PAGEALLOC``, ``CONFIG_DEBUG_MUTEXES``,
64 ``CONFIG_DEBUG_SPINLOCK``, ``CONFIG_DEBUG_ATOMIC_SLEEP``,
65 ``CONFIG_PROVE_RCU`` and ``CONFIG_DEBUG_OBJECTS_RCU_HEAD`` all
66 simultaneously enabled.
68 13) Has been build- and runtime tested with and without ``CONFIG_SMP`` and
71 14) If the patch affects IO/Disk, etc: has been tested with and without
74 15) All codepaths have been exercised with all lockdep features enabled.
76 16) All new ``/proc`` entries are documented under ``Documentation/``
78 17) All new kernel boot parameters are documented in
79 ``Documentation/kernel-parameters.txt``.
81 18) All new module parameters are documented with ``MODULE_PARM_DESC()``
83 19) All new userspace interfaces are documented in ``Documentation/ABI/``.
84 See ``Documentation/ABI/README`` for more information.
85 Patches that change userspace interfaces should be CCed to
86 linux-api@vger.kernel.org.
88 20) Check that it all passes ``make headers_check``.
90 21) Has been checked with injection of at least slab and page-allocation
91 failures. See ``Documentation/fault-injection/``.
93 If the new code is substantial, addition of subsystem-specific fault
94 injection might be appropriate.
96 22) Newly-added code has been compiled with ``gcc -W`` (use
97 ``make EXTRA_CFLAGS=-W``). This will generate lots of noise, but is good
98 for finding bugs like "warning: comparison between signed and unsigned".
100 23) Tested after it has been merged into the -mm patchset to make sure
101 that it still works with all of the other queued patches and various
102 changes in the VM, VFS, and other subsystems.
104 24) All memory barriers {e.g., ``barrier()``, ``rmb()``, ``wmb()``} need a
105 comment in the source code that explains the logic of what they are doing
108 25) If any ioctl's are added by the patch, then also update
109 ``Documentation/ioctl/ioctl-number.txt``.
111 26) If your modified source code depends on or uses any of the kernel
112 APIs or features that are related to the following ``Kconfig`` symbols,
113 then test multiple builds with the related ``Kconfig`` symbols disabled
114 and/or ``=m`` (if that option is available) [not all of these at the
115 same time, just various/random combinations of them]:
117 ``CONFIG_SMP``, ``CONFIG_SYSFS``, ``CONFIG_PROC_FS``, ``CONFIG_INPUT``, ``CONFIG_PCI``, ``CONFIG_BLOCK``, ``CONFIG_PM``, ``CONFIG_MAGIC_SYSRQ``,
118 ``CONFIG_NET``, ``CONFIG_INET=n`` (but latter with ``CONFIG_NET=y``).