First Patch to Linux Kernel

May 30, 2025

Updated on Oct 14, 2026
See changes

The Linux Kernel is one of the largest open source projects on Earth, and it accepts contributions through an email-based workflow.

Recommended reading: Outreachyfirstpatch, a guide to creating your first Linux Kernel patch. The official documentation is Submitting patches.

Kernel Tree

The Linux Kernel project spans many repositories, known as trees. Different subsystems and features are developed in separate subtrees, and eventually Linus Torvalds merges patches from each subtree into the mainline repository.

Coding Style

The Linux Kernel enforces a strict coding style — details in Linux kernel coding style. Patches that violate the coding style get rejected by maintainers.

Run the scripts/checkpatch.pl script before submitting to check your patch against the style rules. If the style-violating code genuinely looks better, it’s usually best to leave it as is; common noise is covered in CheckpatchTips.

Email Workflow

The Linux Kernel uses an email workflow: patches are sent to maintainers by email, and once a maintainer approves them they are merged into the subtree. The scripts/get_maintainer.pl script looks up maintainer addresses and relevant mailing lists from a commit or file.

git send-email is the recommended way to send patches; sourcehut built an email workflow tutorial around it at git-send-email.

Patch Philosophy

Patches are held to strict formatting requirements — details in PatchPhilosophy.

Here is an example patch generated with git format-patch:

From d446483f4cbfc8f89973fc2aea1f2e7351d73c43 Mon Sep 17 00:00:00 2001
From: Xingquan Liu <b1n@b1n.io>
Date: Fri, 30 May 2025 13:08:53 -0400
Subject: [PATCH] ...

[1]

Signed-off-by: Xingquan Liu <b1n@b1n.io>
---
[2]

 test | 0
 1 file changed, 0 insertions(+), 0 deletions(-)
 create mode 100644 test

diff --git a/test b/test
new file mode 100644
index 000000000000..e69de29bb2d1

Subject: [PATCH] ... is the email subject auto-generated from the patch title — don’t edit it directly; instead amend the commit with git commit --amend and regenerate the patch. Patch subjects follow strict formatting rules too; see Patch subject formatting. Signed-off-by: ... is a patch tag certifying that the code complies with the Developer Certificate of Origin; a detailed explanation is in PatchTipsAndTricks. You can enable automatic sign-off with git config format.signOff yes. Below the subject, the area marked [1] is the patch description. Below the --- separator, the area marked [2] takes comments, which are ignored when the patch is applied.

After reviewing your patch, a maintainer may request changes. Regenerate the patch with git format-patch -v2 — the -v2 flag adds a version to the subject: Subject: [PATCH v2] .... You should also add version notes at [2]:

Signed-off-by: Xingquan Liu <b1n@b1n.io>
---
v2:
- Made commit message more clear
- Corrected grammer in code comment
- Used new API instead of depreciated API

 test | 0

A series of related patches is submitted together as a patch set; use git format-patch --cover-letter and write the notes in the separate cover letter file.

Reply Email

Once your patch is submitted, some back-and-forth discussion is often needed to settle on the final approach, and that happens by replying to email. The Linux Kernel requires mail in inline plain text: disable format=flowed, auto-wrapping, and GPG signatures, and use UTF-8 encoding. NeoMutt is the recommended email client; other clients considered good at plain text are listed at Use plain text email. When quoting the original message, use inline replies.