# CVE-2026-99214: drm/vc4: hdmi: Move packet RAM enable to PM runtime


- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Fix available:** Yes
- **Published:** 28 Oct 2026
- **Updated:** 28 Oct 2026
- **Also known as:** BELL-CVE-2026-99214, DEBIAN-CVE-2026-99214, GHSA-83m6-cmv8-x4pq, UBUNTU-CVE-2026-99214

## What is CVE-2026-99214?

CVE-2026-99214 is a vulnerability in Linux, published on 28 Oct 2026. 

### Official description

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

drm/vc4: hdmi: Move packet RAM enable to PM runtime

Audio can be triggered by the HPD handler and start up before video has
been restored, calling vc4_hdmi_write_infoframe() for the audio infoframe.
vc4_hdmi_write_infoframe() needs Packet RAM to be on to store the
infoframe, however, if the video hasn't been enabled,
vc4_hdmi_encoder_post_crtc_enable() hasn't been called and therefore, the
Packet RAM can be disabled by the time vc4_hdmi_write_infoframe() executes,
causing the following splat:

[  201.570266] ------------[ cut here ]------------
[  201.570293] Packet RAM has to be on to store the packet.
[  201.570367] WARNING: drivers/gpu/drm/vc4/vc4_hdmi.c:683 at vc4_hdmi_write_infoframe+0x404/0x494 [vc4], CPU#0: wireplumber/1606
[...]
[  201.658650] Hardware name: Raspberry Pi 4 Model B Rev 1.5 (DT)
[...]
[  201.758499] Call trace:
[  201.760967]  vc4_hdmi_write_infoframe+0x404/0x494 [vc4] (P)
[  201.766607]  vc4_hdmi_write_audio_infoframe+0x1c/0x28 [vc4]
[  201.772247]  write_infoframe+0xbc/0x140 [drm_display_helper]
[  201.777975]  drm_atomic_helper_connector_hdmi_update_audio_infoframe+0x80/0xdc [drm_display_helper]
[  201.787140]  vc4_hdmi_audio_prepare+0x4ac/0x570 [vc4]
[  201.792252]  drm_connector_hdmi_audio_prepare+0x24/0x30 [drm_display_helper]
[  201.799390]  hdmi_codec_prepare+0x100/0x160 [snd_soc_hdmi_codec]
[  201.805471]  snd_soc_pcm_dai_prepare+0xd4/0x100 [snd_soc_core]
[  201.811375]  __soc_pcm_prepare+0x60/0x12c [snd_soc_core]
[  201.816752]  soc_pcm_prepare+0x34/0x58 [snd_soc_core]
[  201.821863]  snd_pcm_do_prepare+0x70/0x8c [snd_pcm]
[  201.826798]  snd_pcm_action_nonatomic+0xe4/0x174 [snd_pcm]
[  201.832350]  snd_pcm_prepare+0xc8/0xd8 [snd_pcm]
[  201.837021]  snd_pcm_common_ioctl+0x458/0x614 [snd_pcm]
[  201.842308]  snd_pcm_ioctl+0x30/0x48 [snd_pcm]
[  201.846802]  __arm64_sys_ioctl+0x88/0xd8
[  201.850769]  invoke_syscall+0x48/0xf4
[  201.854470]  el0_svc_common+0x80/0xd8
[  201.858171]  do_el0_svc+0x1c/0x28
[  201.861520]  el0_svc+0x3c/0xb0
[  201.864605]  el0t_64_sync_handler+0x68/0xdc
[  201.868834]  el0t_64_sync+0x198/0x19c
[  201.872536] ---[ end trace 0000000000000000 ]---

Considering that Packet RAM enable is essentially a power management
configuration, move its enabling/disabling to the Runtime PM hooks.

Note that post_crtc_disable() still stops all infoframes, but keeps Packet
RAM enabled, leaving it to be disabled by runtime suspend.

## Which versions are affected by CVE-2026-99214?


## How do I fix CVE-2026-99214?

Upgrade to a fixed version.

## Is CVE-2026-99214 being exploited?

There is no known exploitation of CVE-2026-99214 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-99214 and fix it if it is affected.

What it is: CVE-2026-99214 is a vulnerability in Linux, published on 28 Oct 2026. 
Exploitation: There is no known exploitation of CVE-2026-99214 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-2026-99214/ (Markdown: https://insights.sbomify.com/CVE-2026-99214/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-99214
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-99214
- OSV: https://osv.dev/vulnerability/CVE-2026-99214

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-99214/
Summaries are generated and may contain mistakes; the official description above is the record.