From: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> Add hints about how to write PCI patches and changelogs. Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> --- Documentation/PCI/00-INDEX | 2 Documentation/PCI/submitting-patches.txt | 153 ++++++++++++++++++++++++++++++ 2 files changed, 155 insertions(+) create mode 100644 Documentation/PCI/submitting-patches.txt diff --git a/Documentation/PCI/00-INDEX b/Documentation/PCI/00-INDEX index 00c9a90b6f38..0f1d1de087f1 100644 --- a/Documentation/PCI/00-INDEX +++ b/Documentation/PCI/00-INDEX @@ -12,6 +12,8 @@ pci.txt - info on the PCI subsystem for device driver authors pcieaer-howto.txt - the PCI Express Advanced Error Reporting Driver Guide HOWTO +submitting-patches.txt + - hints about how to submit PCI patches endpoint/pci-endpoint.txt - guide to add endpoint controller driver and endpoint function driver. endpoint/pci-endpoint-cfs.txt diff --git a/Documentation/PCI/submitting-patches.txt b/Documentation/PCI/submitting-patches.txt new file mode 100644 index 000000000000..d6a694182446 --- /dev/null +++ b/Documentation/PCI/submitting-patches.txt @@ -0,0 +1,153 @@ +Start with Documentation/process/submitting-patches.rst for general +guidance. + +These are things I look at when reviewing patches. Most of the technical +things are obvious or covered elsewhere. Some things here are cosmetic +personal preferences, but consistency makes maintenance easier. I silently +fix up most of the trivial things, so don't get too hung up on the details. + +Write the patch: + + - Make each patch small but complete by itself. Don't worry about making + patches *too* small; it's trivial for me to squash patches together if + necessary. + + - Make sure the kernel builds after every patch. You can't introduce a + problem in one patch and fix it in a subsequent patch. If one of the + autobuilders finds a build issue, I'll revert the patch unless you send + a fix. + + - Please do send whitespace and coding style fixes, but don't mix them + with other substantive changes. It's easier for people to backport + fixes if whitespace changes are at the end of a series. + + - Wrap code and comments to fit in 80 columns. Exception: I prefer + printk strings to be in one piece for searchability, so don't split + quoted strings to make them fit in 80 columns. + + - Follow the existing style for code, names, and indentation. When + you're finished, the file should look like it was all written by one + person. + +Write the changelog title (first line of the changelog): + + - Follow the existing convention Run "git log --oneline <file>" and make + your subject line match previous changes in format, capitalization, and + sentence structure. For example, native host bridge driver patch + titles look like this: + + PCI: vmd: Remove IRQ affinity so we can allocate more IRQs + PCI: mediatek: Add MSI support for MT2712 and MT7622 + PCI: rockchip: Remove IRQ domain if probe fails + + - Write a complete sentence, starting with a capitalized verb. + + - Include specific details, e.g., write "Add XYZ controller support" + instead of "add support for new generation controller". + + - Do not include a trailing period in the title. + +Write the changelog: + + - Make the changelog readable without the title. The changelog is not a + continuation of the title, so it should make sense by itself. Always + include a changelog, even if it is the same as the title. + + - Explain the change (not just "Fix a problem"), but do it as concisely + as possible. Include function names, references to sections of the + spec, URLs for bug reports, etc. This makes reviewing and future + maintenance easier. + + - Capitalize initialisms ("PCI", "IRQ", "ID", "MSI", etc) in all English + text, including title, changelog, and comments. These are usually + written in lower-case in the C code, but please follow normal English + conventions in text. + + - Include "()" after function names and "[]" after array names as a + visual clue that these refer to something in the code. + + - Include dmesg output and stack trace when relevant. Prune details that + aren't relevant, e.g., you can usually remove timestamps and function + addresses. The objective is to concisely illustrate the issue and make + it discoverable by search engines. + + - Use spaces (not tabs) in the changelog because "git log" indents the + changelog and things aligned with tabs won't stay aligned. + + - Wrap changelogs to fit in 80 columns when shown by "git show", which + adds 4 spaces. I use "textwidth=75" in vim. + + - Order tags as suggested by Ingo [1] (extended): + + Fixes: + Link: + Reported-by: + Tested-by: + Signed-off-by: (author) + Signed-off-by: (chain) + Reviewed-by: + Acked-by: + Cc: stable@xxxxxxxxxxxxxxx # 3.4+ + Cc: (other) + + - Include a "Fixes:" reference when you're fixing a previous commit and + copy the author of the previous commit. This helps people figure out + where a change needs to be backported. + + - Include specific commit references when possible, e.g., 'e77f847df54c + ("PCI: rockchip: Add Rockchip PCIe controller support")'. I use this + alias to generate them: + + alias gsr='git --no-pager show -s --abbrev-commit --abbrev=12 --pretty=format:"%h (\"%s\")%n"' + + - Include bugzilla URLs if available (kernel.org bugzilla preferred), + e.g., + + Link: https://bugzilla.redhat.com/show_bug.cgi?id=1409201 + + - Include problem report URLs. Use kernel.org URLs, e.g., + http://lkml.kernel.org/r/<Message-ID>, because they don't depend on + other mirror sites: + + Link: http://lkml.kernel.org/r/4bcbcbc1-7c79-09f0-5071-bc2f53bf6574@xxxxxxxxx + + - Include specific references to the spec when possible, e.g., "PCIe + r3.1, sec 7.8.2". If you're talking about something mentioned in the + spec, use the same name and capitalization as the spec. + + - Include a "Cc: stable@xxxxxxxxxxxxxxx" tag if you want one, and + indicate which kernels need it. + +Post the patch: + + - Use scripts/get_maintainer.pl to find the maintainers of files you're + changing, and copy the maintainers and authors of recent or related + changes. + + - Always copy linux-pci@xxxxxxxxxxxxxxx and linux-kernel@xxxxxxxxxxxxxxx. + I don't apply patches that haven't appeared on the linux-pci mailing + list, even if you send them to me directly. This is partly to make + sure everyone has a chance to review it and partly because I use the + Patchwork tracker [2], which only tracks things on the linux-pci list. + + - If you send more than one patch and they're related, always include a + "[0/n]" cover letter. This makes it easy for me to reply to the cover + letter saying "I applied this series." I use "stg -e -v v1 --to=... + patch1..patchN". + + - If you post a new version, please make sure it includes "[v2]" or + similar in the subject line. If it's a series, I want a new version + of the entire series. I don't want updates of individual patches + within the series -- that's too hard for me to keep track of. It's + perfectly fine if some patches in a v2 series are the same as in the + initial posting. + + - If you want the patch in the current release, include a cover letter + and tell me that. Otherwise, I assume all patches are intended for the + next merge window. + + - If you're really gung-ho, you can go to Patchwork [2] and mark your + superseded patches as "Superseded" so I don't have to do that myself. + +[1] http://lkml.kernel.org/r/20120711080446.GA17713@xxxxxxxxx +[2] https://patchwork.ozlabs.org/project/linux-pci/list/