Description
Kernel Live Patching allows fixing kernel bugs without rebooting
or stopping the workload. It is an essential tool to keep modern
data centers health with fast evolving kernels and workloads.
The Live Patching MC at Linux Plumbers 2026 aims to gather
stakeholders and interested parties to discuss proposed features
and outstanding issues in live patching.
Possible topics for this year:
- Test framework for livepatch subsystem and the new klp-build
toolchain
- Live Patch compatibility with tracing solutions (kprobe, ftrace,
BPF trampoline, etc.)
- Split a live patch module into submodules
- SFrame and livepatch
- Hybrid live patch idea
- Use AI to help build live patch
Work landed based on previous versions of the Live Patching MC:
- Live patching for arm64
- Live patching for Loongarch64
- Live patching for LTO (with klp-build tool chain)
Key Attendees:
- Josh Poimboeuf
- Jiri Kosina
- Miroslav Benes
- Petr Mladek
- Joe Lawrence
- Song Liu
- Dylan Hatch
- Yafang Shao
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Petr Mladek (SUSE)07/10/2026, 15:00
Kernel livepatches are kernel modules which are able to modify the kernel behavior by redirecting kernel functions, calling pre/post patch callbacks, and allocating shadow variables.
The interface between the kernel and the kernel livepatch module is defined in
include/linux/livepatch.h.The API has evolved over the years. But it has stayed backward compatible since the commit...
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Petr Mladek (SUSE), Yafang Shao07/10/2026, 15:30
My employer relies heavily on livepatch to rapidly experiment with new kernel features without interrupting production workloads. Our use cases include:
- Case 1: Deploying a livepatch function as a stable BPF hook.
For example, some proposals for such a use case has already been submitted upstream but has not yet been accepted:
https://lwn.net/Articles/1054030/
...
- Case 1: Deploying a livepatch function as a stable BPF hook.
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Yi Zhu (Google)07/10/2026, 16:00
Abstract
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Large Linux fleets increasingly depend on always-on observability: BPF programs, ftrace, kprobes, kretprobes, and continuous profiling agents are part of the core production control plane. Kernel livepatching depends on some of the same low-level mechanisms, especially dynamic ftrace-based redirection at function entry. In large production environments, we routinely observe fleet... -
Dylan Hatch07/10/2026, 17:00
The Livepatch consistency model [1] requires the kernel to provide reliable stacktrace in order to be fully supported. On x86, the ORC unwinder provides these reliable stacktraces. However, arm64 misses the required support from objtool: it cannot generate ORC unwind tables for arm64. Prior RFCs have proposed to add this support to objtool, but feedback from the upstream community has...
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dongtai guo07/10/2026, 17:30
A series adding LoongArch support to objtool's
Go to contribution pageklp diffsubcommand (the
diffing engine klp-build invokes to generate a patch module) is under
review (v4: ... -
Joe Lawrence (Red Hat), Song Liu (Meta)07/10/2026, 18:00
Abstract
With klp-build now merged into mainline, establishing an automated test
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suite is the logical next step. Historically, maintenance of
kpatch-build, a similar livepatching creation tool, has shown that the
object diff and correlation layer accounts for the vast majority of
regressions. Variations across compiler versions, optimization levels,
LTO modes, CFI, and... -
Kris Van Hees (Oracle USA)
One pain point that is emerging more and more as live patching becomes more common on systems is that although there is coordination between ftrace and live patching (for live patching approaches that use it), the same cannot be said for kprobe and kretprobe. Sudden lack of trace data being generated is often the only indication that the function being traced is being bypassed due to live...
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Song Liu (Meta)
In modern data centers, both livepatch and tracing (kprobe, ftrace, BPF, etc.) are expected to work 100% of the time. However, when livepatch and tracing are attached to the same kernel functions, they may negatively affect each other.
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In this talk, we will present a survey of the compatibility of livepatch and tracing mechanisms, i.e., whether livepatch and different tracing mechanisms can...