1.. _submitchecklist:
  2
  3=======================================
  4Linux Kernel patch submission checklist
  5=======================================
  6
  7Here are some basic things that developers should do if they want to see their
  8kernel patch submissions accepted more quickly.
  9
 10These are all above and beyond the documentation that is provided in
 11:ref:`Documentation/process/submitting-patches.rst <submittingpatches>`
 12and elsewhere regarding submitting Linux kernel patches.
 13
 14Review your code
 15================
 16
 171) If you use a facility then #include the file that defines/declares
 18   that facility.  Don't depend on other header files pulling in ones
 19   that you use.
 20
 212) Check your patch for general style as detailed in
 22   :ref:`Documentation/process/coding-style.rst <codingstyle>`.
 
 
 23
 243) All memory barriers {e.g., ``barrier()``, ``rmb()``, ``wmb()``} need a
 25   comment in the source code that explains the logic of what they are doing
 26   and why.
 27
 28Review Kconfig changes
 29======================
 30
 311) Any new or modified ``CONFIG`` options do not muck up the config menu and
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 32   default to off unless they meet the exception criteria documented in
 33   ``Documentation/kbuild/kconfig-language.rst`` Menu attributes: default value.
 34
 352) All new ``Kconfig`` options have help text.
 36
 373) Has been carefully reviewed with respect to relevant ``Kconfig``
 38   combinations.  This is very hard to get right with testing---brainpower
 39   pays off here.
 40
 41Provide documentation
 42=====================
 43
 441) Include :ref:`kernel-doc <kernel_doc>` to document global kernel APIs.
 45   (Not required for static functions, but OK there also.)
 46
 472) All new ``/proc`` entries are documented under ``Documentation/``
 48
 493) All new kernel boot parameters are documented in
 50   ``Documentation/admin-guide/kernel-parameters.rst``.
 
 51
 524) All new module parameters are documented with ``MODULE_PARM_DESC()``
 
 
 
 53
 545) All new userspace interfaces are documented in ``Documentation/ABI/``.
 55   See ``Documentation/ABI/README`` for more information.
 56   Patches that change userspace interfaces should be CCed to
 57   linux-api@vger.kernel.org.
 
 58
 596) If any ioctl's are added by the patch, then also update
 60   ``Documentation/userspace-api/ioctl/ioctl-number.rst``.
 61
 62Check your code with tools
 63==========================
 64
 651) Check for trivial violations with the patch style checker prior to
 66   submission (``scripts/checkpatch.pl``).
 67   You should be able to justify all violations that remain in
 68   your patch.
 69
 702) Check cleanly with sparse.
 
 71
 723) Use ``make checkstack`` and fix any problems that it finds.
 73   Note that ``checkstack`` does not point out problems explicitly,
 74   but any one function that uses more than 512 bytes on the stack is a
 75   candidate for change.
 76
 77Build your code
 78===============
 
 
 79
 801) Builds cleanly:
 
 81
 82  a) with applicable or modified ``CONFIG`` options ``=y``, ``=m``, and
 83     ``=n``.  No ``gcc`` warnings/errors, no linker warnings/errors.
 84
 85  b) Passes ``allnoconfig``, ``allmodconfig``
 
 
 86
 87  c) Builds successfully when using ``O=builddir``
 
 
 88
 89  d) Any Documentation/ changes build successfully without new warnings/errors.
 90     Use ``make htmldocs`` or ``make pdfdocs`` to check the build and
 91     fix any issues.
 
 
 
 
 
 
 
 
 
 92
 932) Builds on multiple CPU architectures by using local cross-compile tools
 94   or some other build farm. Note that ppc64 is a good architecture for
 95   cross-compilation checking because it tends to use ``unsigned long`` for
 96   64-bit quantities.
 97
 983) Newly-added code has been compiled with ``gcc -W`` (use
 99   ``make KCFLAGS=-W``).  This will generate lots of noise, but is good
100   for finding bugs like "warning: comparison between signed and unsigned".
101
1024) If your modified source code depends on or uses any of the kernel
103   APIs or features that are related to the following ``Kconfig`` symbols,
104   then test multiple builds with the related ``Kconfig`` symbols disabled
105   and/or ``=m`` (if that option is available) [not all of these at the
106   same time, just various/random combinations of them]:
107
108   ``CONFIG_SMP``, ``CONFIG_SYSFS``, ``CONFIG_PROC_FS``, ``CONFIG_INPUT``,
109   ``CONFIG_PCI``, ``CONFIG_BLOCK``, ``CONFIG_PM``, ``CONFIG_MAGIC_SYSRQ``,
110   ``CONFIG_NET``, ``CONFIG_INET=n`` (but latter with ``CONFIG_NET=y``).
111
112Test your code
113==============
114
1151) Has been tested with ``CONFIG_PREEMPT``, ``CONFIG_DEBUG_PREEMPT``,
116   ``CONFIG_SLUB_DEBUG``, ``CONFIG_DEBUG_PAGEALLOC``, ``CONFIG_DEBUG_MUTEXES``,
117   ``CONFIG_DEBUG_SPINLOCK``, ``CONFIG_DEBUG_ATOMIC_SLEEP``,
118   ``CONFIG_PROVE_RCU`` and ``CONFIG_DEBUG_OBJECTS_RCU_HEAD`` all
119   simultaneously enabled.
120
1212) Has been build- and runtime tested with and without ``CONFIG_SMP`` and
122   ``CONFIG_PREEMPT.``
123
1243) All codepaths have been exercised with all lockdep features enabled.
125
1264) Has been checked with injection of at least slab and page-allocation
127   failures.  See ``Documentation/fault-injection/``.
128   If the new code is substantial, addition of subsystem-specific fault
129   injection might be appropriate.
130
1315) Tested with the most recent tag of linux-next to make sure that it still
132   works with all of the other queued patches and various changes in the VM,
133   VFS, and other subsystems.

  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) Has been checked with injection of at least slab and page-allocation
 93    failures.  See ``Documentation/fault-injection/``.
 94
 95    If the new code is substantial, addition of subsystem-specific fault
 96    injection might be appropriate.
 97
 9820) Newly-added code has been compiled with ``gcc -W`` (use
 99    ``make KCFLAGS=-W``).  This will generate lots of noise, but is good
100    for finding bugs like "warning: comparison between signed and unsigned".
101
10221) Tested after it has been merged into the -mm patchset to make sure
103    that it still works with all of the other queued patches and various
104    changes in the VM, VFS, and other subsystems.
105
10622) All memory barriers {e.g., ``barrier()``, ``rmb()``, ``wmb()``} need a
107    comment in the source code that explains the logic of what they are doing
108    and why.
109
11023) If any ioctl's are added by the patch, then also update
111    ``Documentation/userspace-api/ioctl/ioctl-number.rst``.
112
11324) If your modified source code depends on or uses any of the kernel
114    APIs or features that are related to the following ``Kconfig`` symbols,
115    then test multiple builds with the related ``Kconfig`` symbols disabled
116    and/or ``=m`` (if that option is available) [not all of these at the
117    same time, just various/random combinations of them]:
118
119    ``CONFIG_SMP``, ``CONFIG_SYSFS``, ``CONFIG_PROC_FS``, ``CONFIG_INPUT``, ``CONFIG_PCI``, ``CONFIG_BLOCK``, ``CONFIG_PM``, ``CONFIG_MAGIC_SYSRQ``,
120    ``CONFIG_NET``, ``CONFIG_INET=n`` (but latter with ``CONFIG_NET=y``).