# CVE-2025-21645: platform/x86/amd/pmc: Only disable IRQ1 wakeup where i8042 actually enabled it

> A logic error in the AMD PMC driver causes an unbalanced IRQ wake disable warning during hibernation, potentially leading to system instability or denial of service.

- **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 19 Jan 2025
- **Updated:** 15 Oct 2026
- **Also known as:** BELL-CVE-2025-21645, DEBIAN-CVE-2025-21645, GHSA-2phg-f479-57pq, ROOT-OS-DEBIAN-12-CVE-2025-21645, UBUNTU-CVE-2025-21645

## What is CVE-2025-21645?

CVE-2025-21645 is a medium-severity denial of service vulnerability in Linux kernel, published on 19 Jan 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:

platform/x86/amd/pmc: Only disable IRQ1 wakeup where i8042 actually enabled it

Wakeup for IRQ1 should be disabled only in cases where i8042 had
actually enabled it, otherwise "wake_depth" for this IRQ will try to
drop below zero and there will be an unpleasant WARN() logged:

kernel: atkbd serio0: Disabling IRQ1 wakeup source to avoid platform firmware bug
kernel: ------------[ cut here ]------------
kernel: Unbalanced IRQ 1 wake disable
kernel: WARNING: CPU: 10 PID: 6431 at kernel/irq/manage.c:920 irq_set_irq_wake+0x147/0x1a0

The PMC driver uses DEFINE_SIMPLE_DEV_PM_OPS() to define its dev_pm_ops
which sets amd_pmc_suspend_handler() to the .suspend, .freeze, and
.poweroff handlers. i8042_pm_suspend(), however, is only set as
the .suspend handler.

Fix the issue by call PMC suspend handler only from the same set of
dev_pm_ops handlers as i8042_pm_suspend(), which currently means just
the .suspend handler.

To reproduce this issue try hibernating (S4) the machine after a fresh boot
without putting it into s2idle first.

[ij: edited the commit message.]

## Which versions are affected by CVE-2025-21645?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2025-21645?

Apply the vendor's patch.

## Is CVE-2025-21645 being exploited?

There is no known exploitation of CVE-2025-21645 in the wild and no public exploit code.

## Other vulnerabilities in Linux kernel

- [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild)
- [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild)
- [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild)
- [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild)
- [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-21645 and fix it if it is affected.

What it is: CVE-2025-21645 is a medium-severity denial of service vulnerability in Linux kernel, published on 19 Jan 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-2025-21645 in the wild and no public exploit code.

Affected product: Linux kernel. 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-2025-21645/ (Markdown: https://insights.sbomify.com/CVE-2025-21645/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-21645
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-21645
- OSV: https://osv.dev/vulnerability/CVE-2025-21645

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-21645/
Summaries are generated and may contain mistakes; the official description above is the record.