1 .. _submitchecklist: 1 .. _submitchecklist:
2 2
3 ======================================= 3 =======================================
4 Linux Kernel patch submission checklist 4 Linux Kernel patch submission checklist
5 ======================================= 5 =======================================
6 6
7 Here are some basic things that developers sho 7 Here are some basic things that developers should do if they want to see their
8 kernel patch submissions accepted more quickly 8 kernel patch submissions accepted more quickly.
9 9
10 These are all above and beyond the documentati 10 These are all above and beyond the documentation that is provided in
11 :ref:`Documentation/process/submitting-patches 11 :ref:`Documentation/process/submitting-patches.rst <submittingpatches>`
12 and elsewhere regarding submitting Linux kerne 12 and elsewhere regarding submitting Linux kernel patches.
13 13
14 Review your code 14 Review your code
15 ================ 15 ================
16 16
17 1) If you use a facility then #include the fil 17 1) If you use a facility then #include the file that defines/declares
18 that facility. Don't depend on other heade 18 that facility. Don't depend on other header files pulling in ones
19 that you use. 19 that you use.
20 20
21 2) Check your patch for general style as detai 21 2) Check your patch for general style as detailed in
22 :ref:`Documentation/process/coding-style.rs 22 :ref:`Documentation/process/coding-style.rst <codingstyle>`.
23 23
24 3) All memory barriers {e.g., ``barrier()``, ` 24 3) All memory barriers {e.g., ``barrier()``, ``rmb()``, ``wmb()``} need a
25 comment in the source code that explains th 25 comment in the source code that explains the logic of what they are doing
26 and why. 26 and why.
27 27
28 Review Kconfig changes 28 Review Kconfig changes
29 ====================== 29 ======================
30 30
31 1) Any new or modified ``CONFIG`` options do n 31 1) Any new or modified ``CONFIG`` options do not muck up the config menu and
32 default to off unless they meet the excepti 32 default to off unless they meet the exception criteria documented in
33 ``Documentation/kbuild/kconfig-language.rst 33 ``Documentation/kbuild/kconfig-language.rst`` Menu attributes: default value.
34 34
35 2) All new ``Kconfig`` options have help text. 35 2) All new ``Kconfig`` options have help text.
36 36
37 3) Has been carefully reviewed with respect to 37 3) Has been carefully reviewed with respect to relevant ``Kconfig``
38 combinations. This is very hard to get rig 38 combinations. This is very hard to get right with testing---brainpower
39 pays off here. 39 pays off here.
40 40
41 Provide documentation 41 Provide documentation
42 ===================== 42 =====================
43 43
44 1) Include :ref:`kernel-doc <kernel_doc>` to d 44 1) Include :ref:`kernel-doc <kernel_doc>` to document global kernel APIs.
45 (Not required for static functions, but OK 45 (Not required for static functions, but OK there also.)
46 46
47 2) All new ``/proc`` entries are documented un 47 2) All new ``/proc`` entries are documented under ``Documentation/``
48 48
49 3) All new kernel boot parameters are document 49 3) All new kernel boot parameters are documented in
50 ``Documentation/admin-guide/kernel-paramete 50 ``Documentation/admin-guide/kernel-parameters.rst``.
51 51
52 4) All new module parameters are documented wi 52 4) All new module parameters are documented with ``MODULE_PARM_DESC()``
53 53
54 5) All new userspace interfaces are documented 54 5) All new userspace interfaces are documented in ``Documentation/ABI/``.
55 See ``Documentation/ABI/README`` for more i 55 See ``Documentation/ABI/README`` for more information.
56 Patches that change userspace interfaces sh 56 Patches that change userspace interfaces should be CCed to
57 linux-api@vger.kernel.org. 57 linux-api@vger.kernel.org.
58 58
59 6) If any ioctl's are added by the patch, then 59 6) If any ioctl's are added by the patch, then also update
60 ``Documentation/userspace-api/ioctl/ioctl-n 60 ``Documentation/userspace-api/ioctl/ioctl-number.rst``.
61 61
62 Check your code with tools 62 Check your code with tools
63 ========================== 63 ==========================
64 64
65 1) Check for trivial violations with the patch 65 1) Check for trivial violations with the patch style checker prior to
66 submission (``scripts/checkpatch.pl``). 66 submission (``scripts/checkpatch.pl``).
67 You should be able to justify all violation 67 You should be able to justify all violations that remain in
68 your patch. 68 your patch.
69 69
70 2) Check cleanly with sparse. 70 2) Check cleanly with sparse.
71 71
72 3) Use ``make checkstack`` and fix any problem 72 3) Use ``make checkstack`` and fix any problems that it finds.
73 Note that ``checkstack`` does not point out 73 Note that ``checkstack`` does not point out problems explicitly,
74 but any one function that uses more than 51 74 but any one function that uses more than 512 bytes on the stack is a
75 candidate for change. 75 candidate for change.
76 76
77 Build your code 77 Build your code
78 =============== 78 ===============
79 79
80 1) Builds cleanly: 80 1) Builds cleanly:
81 81
82 a) with applicable or modified ``CONFIG`` op 82 a) with applicable or modified ``CONFIG`` options ``=y``, ``=m``, and
83 ``=n``. No ``gcc`` warnings/errors, no l 83 ``=n``. No ``gcc`` warnings/errors, no linker warnings/errors.
84 84
85 b) Passes ``allnoconfig``, ``allmodconfig`` 85 b) Passes ``allnoconfig``, ``allmodconfig``
86 86
87 c) Builds successfully when using ``O=buildd 87 c) Builds successfully when using ``O=builddir``
88 88
89 d) Any Documentation/ changes build successf 89 d) Any Documentation/ changes build successfully without new warnings/errors.
90 Use ``make htmldocs`` or ``make pdfdocs`` 90 Use ``make htmldocs`` or ``make pdfdocs`` to check the build and
91 fix any issues. 91 fix any issues.
92 92
93 2) Builds on multiple CPU architectures by usi 93 2) Builds on multiple CPU architectures by using local cross-compile tools
94 or some other build farm. Note that ppc64 i 94 or some other build farm. Note that ppc64 is a good architecture for
95 cross-compilation checking because it tends 95 cross-compilation checking because it tends to use ``unsigned long`` for
96 64-bit quantities. 96 64-bit quantities.
97 97
98 3) Newly-added code has been compiled with ``g 98 3) Newly-added code has been compiled with ``gcc -W`` (use
99 ``make KCFLAGS=-W``). This will generate l 99 ``make KCFLAGS=-W``). This will generate lots of noise, but is good
100 for finding bugs like "warning: comparison 100 for finding bugs like "warning: comparison between signed and unsigned".
101 101
102 4) If your modified source code depends on or 102 4) If your modified source code depends on or uses any of the kernel
103 APIs or features that are related to the fo 103 APIs or features that are related to the following ``Kconfig`` symbols,
104 then test multiple builds with the related 104 then test multiple builds with the related ``Kconfig`` symbols disabled
105 and/or ``=m`` (if that option is available) 105 and/or ``=m`` (if that option is available) [not all of these at the
106 same time, just various/random combinations 106 same time, just various/random combinations of them]:
107 107
108 ``CONFIG_SMP``, ``CONFIG_SYSFS``, ``CONFIG_ 108 ``CONFIG_SMP``, ``CONFIG_SYSFS``, ``CONFIG_PROC_FS``, ``CONFIG_INPUT``,
109 ``CONFIG_PCI``, ``CONFIG_BLOCK``, ``CONFIG_ 109 ``CONFIG_PCI``, ``CONFIG_BLOCK``, ``CONFIG_PM``, ``CONFIG_MAGIC_SYSRQ``,
110 ``CONFIG_NET``, ``CONFIG_INET=n`` (but latt 110 ``CONFIG_NET``, ``CONFIG_INET=n`` (but latter with ``CONFIG_NET=y``).
111 111
112 Test your code 112 Test your code
113 ============== 113 ==============
114 114
115 1) Has been tested with ``CONFIG_PREEMPT``, `` 115 1) Has been tested with ``CONFIG_PREEMPT``, ``CONFIG_DEBUG_PREEMPT``,
116 ``CONFIG_SLUB_DEBUG``, ``CONFIG_DEBUG_PAGEA 116 ``CONFIG_SLUB_DEBUG``, ``CONFIG_DEBUG_PAGEALLOC``, ``CONFIG_DEBUG_MUTEXES``,
117 ``CONFIG_DEBUG_SPINLOCK``, ``CONFIG_DEBUG_A 117 ``CONFIG_DEBUG_SPINLOCK``, ``CONFIG_DEBUG_ATOMIC_SLEEP``,
118 ``CONFIG_PROVE_RCU`` and ``CONFIG_DEBUG_OBJ 118 ``CONFIG_PROVE_RCU`` and ``CONFIG_DEBUG_OBJECTS_RCU_HEAD`` all
119 simultaneously enabled. 119 simultaneously enabled.
120 120
121 2) Has been build- and runtime tested with and 121 2) Has been build- and runtime tested with and without ``CONFIG_SMP`` and
122 ``CONFIG_PREEMPT.`` 122 ``CONFIG_PREEMPT.``
123 123
124 3) All codepaths have been exercised with all 124 3) All codepaths have been exercised with all lockdep features enabled.
125 125
126 4) Has been checked with injection of at least 126 4) Has been checked with injection of at least slab and page-allocation
127 failures. See ``Documentation/fault-inject 127 failures. See ``Documentation/fault-injection/``.
128 If the new code is substantial, addition of 128 If the new code is substantial, addition of subsystem-specific fault
129 injection might be appropriate. 129 injection might be appropriate.
130 130
131 5) Tested with the most recent tag of linux-ne 131 5) Tested with the most recent tag of linux-next to make sure that it still
132 works with all of the other queued patches 132 works with all of the other queued patches and various changes in the VM,
133 VFS, and other subsystems. 133 VFS, and other subsystems.
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.