1.. _submitchecklist: 2 3Linux Kernel patch submission checklist 4~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 5 6Here are some basic things that developers should do if they want to see their 7kernel patch submissions accepted more quickly. 8 9These are all above and beyond the documentation that is provided in 10:ref:`Documentation/process/submitting-patches.rst <submittingpatches>` 11and elsewhere regarding submitting Linux kernel patches. 12 13 141) If you use a facility then #include the file that defines/declares 15 that facility. Don't depend on other header files pulling in ones 16 that you use. 17 182) Builds cleanly: 19 20 a) with applicable or modified ``CONFIG`` options ``=y``, ``=m``, and 21 ``=n``. No ``gcc`` warnings/errors, no linker warnings/errors. 22 23 b) Passes ``allnoconfig``, ``allmodconfig`` 24 25 c) Builds successfully when using ``O=builddir`` 26 27 d) Any Documentation/ changes build successfully without new warnings/errors. 28 Use ``make htmldocs`` or ``make pdfdocs`` to check the build and 29 fix any issues. 30 313) Builds on multiple CPU architectures by using local cross-compile tools 32 or some other build farm. 33 344) ppc64 is a good architecture for cross-compilation checking because it 35 tends to use ``unsigned long`` for 64-bit quantities. 36 375) Check your patch for general style as detailed in 38 :ref:`Documentation/process/coding-style.rst <codingstyle>`. 39 Check for trivial violations with the patch style checker prior to 40 submission (``scripts/checkpatch.pl``). 41 You should be able to justify all violations that remain in 42 your patch. 43 446) Any new or modified ``CONFIG`` options do not muck up the config menu and 45 default to off unless they meet the exception criteria documented in 46 ``Documentation/kbuild/kconfig-language.rst`` Menu attributes: default value. 47 487) All new ``Kconfig`` options have help text. 49 508) Has been carefully reviewed with respect to relevant ``Kconfig`` 51 combinations. This is very hard to get right with testing -- brainpower 52 pays off here. 53 549) Check cleanly with sparse. 55 5610) Use ``make checkstack`` and fix any problems that it finds. 57 58 .. note:: 59 60 ``checkstack`` does not point out problems explicitly, 61 but any one function that uses more than 512 bytes on the stack is a 62 candidate for change. 63 6411) Include :ref:`kernel-doc <kernel_doc>` to document global kernel APIs. 65 (Not required for static functions, but OK there also.) Use 66 ``make htmldocs`` or ``make pdfdocs`` to check the 67 :ref:`kernel-doc <kernel_doc>` and fix any issues. 68 6912) Has been tested with ``CONFIG_PREEMPT``, ``CONFIG_DEBUG_PREEMPT``, 70 ``CONFIG_DEBUG_SLAB``, ``CONFIG_DEBUG_PAGEALLOC``, ``CONFIG_DEBUG_MUTEXES``, 71 ``CONFIG_DEBUG_SPINLOCK``, ``CONFIG_DEBUG_ATOMIC_SLEEP``, 72 ``CONFIG_PROVE_RCU`` and ``CONFIG_DEBUG_OBJECTS_RCU_HEAD`` all 73 simultaneously enabled. 74 7513) Has been build- and runtime tested with and without ``CONFIG_SMP`` and 76 ``CONFIG_PREEMPT.`` 77 7814) All codepaths have been exercised with all lockdep features enabled. 79 8015) All new ``/proc`` entries are documented under ``Documentation/`` 81 8216) All new kernel boot parameters are documented in 83 ``Documentation/admin-guide/kernel-parameters.rst``. 84 8517) All new module parameters are documented with ``MODULE_PARM_DESC()`` 86 8718) All new userspace interfaces are documented in ``Documentation/ABI/``. 88 See ``Documentation/ABI/README`` for more information. 89 Patches that change userspace interfaces should be CCed to 90 linux-api@vger.kernel.org. 91 9219) Check that it all passes ``make headers_check``. 93 9420) Has been checked with injection of at least slab and page-allocation 95 failures. See ``Documentation/fault-injection/``. 96 97 If the new code is substantial, addition of subsystem-specific fault 98 injection might be appropriate. 99 10021) Newly-added code has been compiled with ``gcc -W`` (use 101 ``make EXTRA_CFLAGS=-W``). This will generate lots of noise, but is good 102 for finding bugs like "warning: comparison between signed and unsigned". 103 10422) Tested after it has been merged into the -mm patchset to make sure 105 that it still works with all of the other queued patches and various 106 changes in the VM, VFS, and other subsystems. 107 10823) All memory barriers {e.g., ``barrier()``, ``rmb()``, ``wmb()``} need a 109 comment in the source code that explains the logic of what they are doing 110 and why. 111 11224) If any ioctl's are added by the patch, then also update 113 ``Documentation/userspace-api/ioctl/ioctl-number.rst``. 114 11525) If your modified source code depends on or uses any of the kernel 116 APIs or features that are related to the following ``Kconfig`` symbols, 117 then test multiple builds with the related ``Kconfig`` symbols disabled 118 and/or ``=m`` (if that option is available) [not all of these at the 119 same time, just various/random combinations of them]: 120 121 ``CONFIG_SMP``, ``CONFIG_SYSFS``, ``CONFIG_PROC_FS``, ``CONFIG_INPUT``, ``CONFIG_PCI``, ``CONFIG_BLOCK``, ``CONFIG_PM``, ``CONFIG_MAGIC_SYSRQ``, 122 ``CONFIG_NET``, ``CONFIG_INET=n`` (but latter with ``CONFIG_NET=y``). 123