# CVE-2025-40136: crypto: hisilicon/qm - request reserved interrupt for virtual function

> A missing interrupt registration in the Hisilicon QM driver causes a kernel warning and potential instability when virtual functions are passed through to VMs with GICv4 enabled.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 12 Nov 2025
- **Updated:** 21 Oct 2026
- **Also known as:** BELL-CVE-2025-40136, DEBIAN-CVE-2025-40136, GHSA-p5f2-4xpv-wwqj, ROOT-OS-DEBIAN-12-CVE-2025-40136, ROOT-OS-DEBIAN-13-CVE-2025-40136, ROOT-OS-UBUNTU-2404-CVE-2025-40136, UBUNTU-CVE-2025-40136

## What is CVE-2025-40136?

CVE-2025-40136 is a denial of service vulnerability in Linux, published on 12 Nov 2025. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

In the Linux kernel, the following vulnerability has been resolved:

crypto: hisilicon/qm - request reserved interrupt for virtual function

The device interrupt vector 3 is an error interrupt for
physical function and a reserved interrupt for virtual function.
However, the driver has not registered the reserved interrupt for
virtual function. When allocating interrupts, the number of interrupts
is allocated based on powers of two, which includes this interrupt.
When the system enables GICv4 and the virtual function passthrough
to the virtual machine, releasing the interrupt in the driver
triggers a warning.

The WARNING report is:
WARNING: CPU: 62 PID: 14889 at arch/arm64/kvm/vgic/vgic-its.c:852 its_free_ite+0x94/0xb4

Therefore, register a reserved interrupt for VF and set the
IRQF_NO_AUTOEN flag to avoid that warning.

## Which versions are affected by CVE-2025-40136?


## How do I fix CVE-2025-40136?

Apply the vendor's patch.

## Is CVE-2025-40136 being exploited?

There is no known exploitation of CVE-2025-40136 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-40136 and fix it if it is affected.

What it is: CVE-2025-40136 is a denial of service vulnerability in Linux, published on 12 Nov 2025. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2025-40136 in the wild and no public exploit code.

Affected product: Linux. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2025-40136/ (Markdown: https://insights.sbomify.com/CVE-2025-40136/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-40136
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-40136
- OSV: https://osv.dev/vulnerability/CVE-2025-40136

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-40136/
Summaries are generated and may contain mistakes; the official description above is the record.